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1 Table 2. Radiometric ages from the Greater Antilles and the Virgin Islands, including K/Ar, 40Ar/39Ar, fission-track, Rb/Sr, U/Pb, Re/Os, and Lu/Hf age determinations. [Methods: K/Ar, potassium-argon; 40/39, 40Ar/39Ar (includes plateau, total fusion, integrated, or isochron ages); Lu/Hf, lutetium-hafnium; Rb/Sr, rubidium-strontium; Re/Os, rhenium-osmium; U/Pb, uranium-lead (LA-ICP-MS, laser ablation inductively coupled plasma mass spectrometry; SHRIMP, sensitive high-resolution ion microprobe; or TIMS, thermal ionization mass spectrometry); Other abbreviations: K, potassium; K-feldspar, potassium feldspar; MORB, midocean-ridge basalt; MSWD, mean square weighted deviation; n/a, not available or applicable as appropriate; T (as in, ‘high T fractions’), temperature] Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) British Virgin Islands PI-13A 18.332 -64.5719 Diorite Zircon TIMS Multigrain 30.64 0.46 The diorite phase of the Peter Island suite yields two concordant and two normally discordant fractions spanning 30.62 to 30.83 Ma, with a 206Pb/238U weighted average of 30.6 Ma. This age is corroborated by LA-ICP-MS analysis of 11 grains giving weighted mean age of 30.64±0.46 Ma (MSWD = 1.09; C. Allen, personal commun., 2010). One concordant fraction gives an older age of 32.5 Ma, interpreted to reflect inheritance of zircon cores from earlier magmas. Schrecengost, 2010 VI-7 18.3723 -64.7425 Granodiorite Hornblende K/Ar 23.7 0.3 Reported as Narrows pluton. No location provided; crudely approximate location here is a guess based on location of pluton near Fort Recovery. Date recalculated using constants of Steiger and Jager (1977). Kesler and Sutter, 1979; Vila and others, 1986; Rankin, 2002 VI 29 18.383 -64.6723 Diorite Whole rock K/Ar 42.80 2.14 Narrows pluton, Fort Recovery on Tortola. Vila and others, 1986; Rankin, 2002 VIJ 453 18.383 -64.6723 Granite Whole rock K/Ar 35.37 1.77 Granite, Virgin Gorda batholith at The Baths, Virgin Gorda. Vila and others, 1986; Rankin, 2002 VG-05 18.4264 -64.4452 Granodiorite Zircon TIMS Multigrain 37.62 0.05 Six concordant fractions of VG-05 cluster and yield an age of 37.62±0.05 Ma (MSWD = 0.53). Schrecengost, 2010 VI-8 18.434 -64.427 Granodiorite Biotite K/Ar 31.9 0.4 Reported as Copper Mine Point granodiorite, same pluton as Cox and others (1977) sample V-G-1. Location derived from Wikipedia for Copper Mine Point copper mine; accuracy of location relative to this sample is unknown. Date recalculated using constants of Steiger and Jager (1977). Kesler and Sutter, 1979; Vila and others, 1986; Rankin, 2002 V-G-1 18.4375 -64.4361 Quartz diorite Hornblende K/Ar 35.1 1.6 Quartz diorite (also reported as granodiorite) from the Virgin Islands batholith; date recalculated using constants of Steiger and Jager (1977). Copper Mine Point, Virgin Gorda batholith. Cox and others, 1977; Vila and others, 1986; Kesler and Sutter, 1979; Rankin, 2002 Biotite K/Ar 37.2 0.9 VG-06 18.4414 -64.4384 Tonalite Zircon TIMS Multigrain 37.6 Two concordant fractions of VG-06 cluster at 37.6. No error reported. Schrecengost, 2010 TTL 459 18.4418 -64.5477 Diorite Whole rock K/Ar 38.85 1.94 Virgin Gorda batholith, Beef Island. Vila and others, 1986; Rankin, 2002 BI-26 18.4430 -64.5433 Tonalite Zircon TIMS Multigrain 42.55 0.44 Four concordant fractions of BI-26, the tonalite phase of the Beef Island suite, span from 42.29 to 42.43 Ma. LA-ICP-MS of seven zircon grains from BI-26 provides a weighted age of 42.55±0.44 Ma (MSWD = 0.27; C. Allen, personal commun., 2010). Schrecengost, 2010 VG-01 18.4867 -64.3886 Quartz diorite Zircon TIMS Multigrain 43.56 0.08 Four concordant fractions of the quartz diorite phase of the North Sound suite, VG-01, span from 43.53 to 43.62 Ma. These four fractions, together, yield an age of 43.56±0.08 Ma (MSWD = 0.082). Schrecengost, 2010 VIJ 451 18.484 -64.389 Gabbro Whole rock K/Ar 60.36 3.02 Gabbro, Virgin Gorda batholith near Virgin Peak, Virgin Gorda Vila and others, 1986; Rankin, 2002 Cuba CU49 19.9339 -76.8278 Trondhjemite Zircon U/Pb SHRIMP 60.2 2.6 Turquino Massif, 3 grains. Coordinates adjusted northward to place site onshore. Rojas-Agramonte and others, 2004, 2006 Unknown 19.9380 -76.7930 Unknown Zircon U/Pb 56 Turquino Massif. No error reported. Kysar and others, 1998; Rojas-Agramonte and others, 2004 4382 19.9443 -75.6571 Quartz diorite Whole rock K/Ar 47.8 6 Daiquiri quartz diorite, 20 km east of Santiago de Cuba, southern Oriente Province. Latitude and longitude approximate. Early to middle Eocene. Sierra Maestra. Late in Laramide orogeny. Original reported age was 49 Ma, recalculated here using constants of Steiger and Jager (1977). Two determinations were made and average was reported. Individual determinations were (recalculated) 45.3 and 49.1 Ma. Same as Meyerhoff's sample 7. Laverov and others, 1967; Meyerhoff and others, 1969 CU40 19.9464 -76.7171 Tonalite Zircon Fission-track 44 4 Peladero Massif, 7 grains. Rojas-Agramonte and others, 2006 Biotite 40/39 Integrated 53.8 3.8 Peladero Massif. Integrated age, steps 4 to 14. CU60 19.9464 -76.7173 Tonalite Apatite Fission-track 31 10 Turquino Massif, 20 grains. Rojas-Agramonte and others, 2006 Zircon U/Pb SHRIMP 55.4 0.7 Turquino Massif, 8 grains. Rojas-Agramonte and others, 2004, 2006 CU5 19.9558 -75.6786 Tonalite Zircon Fission-track 36 4 Daiquiri Massif southeast of Santiago de Cuba, 9 grains. Rojas-Agramonte and others, 2006 U/Pb SHRIMP 50.1 .5 Daiquiri Massif southeast of Santiago de Cuba, 5 grains. Rojas-Agramonte and others, 2004, 2006 U/Pb SHRIMP 310.8 3.4 Daiquiri Massif southeast of Santiago de Cuba, 1 grain, either inherited or possible laboratory contamination. Rojas-Agramonte and others, 2004, 2006 2 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued 4380 19.9607 -76.0104 Diorite Whole rock K/Ar 58.1 8 Nima-Nima diorite, 20 km west of Santiago de Cuba, southern Oriente Province. Latitude and longitude approximate. Paleocene. Sierra Maestra. Late in Laramide orogeny. Original reported age was 58 Ma, recalculated using constants of Steiger and Jager (1977). Two determinations were made and average was reported. Individual determinations were (recalculated) 53.5 and 60.4 Ma. Same as Meyerhoff's sample 9. Laverov and others, 1967; Meyerhoff and others, 1969 4383 19.9607 -76.0107 Plagiogranite Whole rock K/Ar 44.2 6 Nima-Nima plagiogranite porphyry, 20 km west of Santiago de Cuba, southern Oriente Province. Latitude and longitude approximate. Early to middle Eocene. Sierra Maestra. Late in Laramide orogeny. Original reported age was 46 Ma, recalculated using constants of Steiger and Jager (1977). Two determinations were made and average was reported. Individual determinations were (recalculated) 45.2 and 43.3 Ma. Same as Meyerhoff's sample 8. Laverov and others, 1967; Meyerhoff and others, 1969 Unknown 19.9610 -75.6760 Dacite Zircon U/Pb 49.7 .3 Flow structurally above Daiquiri intrusion. Kysar and others, 1998; Rojas-Agramonte and others, 2004 Unknown 19.961 -75.676 Quartz diorite Zircon U/Pb 49.8 .2 Daiquiri Massif. Kysar and others, 1998; Rojas-Agramonte and others, 2004 Unknown 19.961 -75.676 Gabbro-diorite Zircon U/Pb 50.2 .1 Daiquiri Massif. Kysar and others, 1998; Rojas-Agramonte and others, 2004 Unknown 19.9610 -75.6760 Andesite Zircon U/Pb 50.6 .1 Dike. Kysar and others, 1998; Rojas-Agramonte and others, 2004 Unknown 19.961 -75.676 Gabbro Unknown Unknown 76 3.8 Rodriguez-Crombet and others, 1997 Unknown 19.961 -75.676 Quartz diorite Unknown Unknown 39 4 Alioshin and others, 1975; Rojas- Agramonte and others, 2006 Unknown 19.961 -75.676 Tonalite Unknown Unknown 54 5 Alioshin and others, 1975; Rojas- Agramonte and others, 2006 Unknown 19.961 -75.954 Quartz diorite Unknown Unknown 42 5 Eguipko and Perez, 1976 Unknown 19.961 -75.676 Tonalite Unknown Unknown 44 4 Eguipko and Perez, 1976 Unknown 19.961 -75.954 Quartz diorite Unknown K/Ar 58 5 Laverov and Cabrera, 1967 Unknown 19.961 -75.954 Quartz diorite Unknown K/Ar 58 5 Laverov and Cabrera, 1967 CU30 19.9628 -75.7864 Tonalite Zircon U/Pb SHRIMP 50.1 .5 Nima-Nima Massif southwest of Santiago de Cuba, 6 grains. Rojas-Agramonte and others, 2004, 2006 Zircon Fission-track 32 3 Nima-Nima Massif southwest of Santiago de Cuba, 8 grains. Rojas-Agramonte and others, 2006 Apatite Fission-track 44 13 Nima-Nima Massif southwest of Santiago de Cuba, 30 grains. CU29 19.9636 -75.9889 Tonalite Zircon U/Pb SHRIMP 50.5 .5 Nima-Nima Massif southwest of Santiago de Cuba, 8 grains. Rojas-Agramonte and others, 2004, 2006 Zircon Fission-track 39 4 Nima-Nima Massif southwest of Santiago de Cuba, 8 grains. Rojas-Agramonte and others, 2006 Biotite 40/39 Integrated 49.9 2.4 Nima-Nima Massif southwest of Santiago de Cuba. Integrated age, steps 8 to 19. CU32 19.9669 -75.9489 Tonalite Zircon Fission-track 41 3 Nima-Nima Massif southwest of Santiago de Cuba. 15 grains. Rojas-Agramonte and others, 2006 D316 20.0942 -74.765 Amphibolite Unknown, whole rock? K/Ar 80 10 All locations from source are approximate generalities. Garnet amphibolite, inclusion in serpentinite mélange, North of San Antonio del Sur, Guantanamo Province. Reported age was 10 Ma which is probably the error, calculated age based on reported analytical data. Somin and others, 1992 CU147B 19.9697 -76.6836 Tonalite Zircon U/Pb SHRIMP 48.2 .4 Peladero Massif, 7 grains. Rojas-Agramonte and others, 2004, 2006 Unknown 19.997 -76.466 Quartz diorite Zircon U/Pb 46.9 .1 Guama Massif. Kysar and others, 1998; Rojas-Agramonte and others, 2004 D322-1 20.0942 -74.765 Schist Unknown, WR? K/Ar 86.8 7 All locations from source are approximate generalities. Mica-quartz-albite schist, inclusion in serpentinite mélange from north of San Antonio del Sur, Guantanamo Province. Reported age was 86 Ma, recalculated here based on reported analytical data. Duplicate sample ID in source. Somin and others, 1992 D331 20.0942 -74.765 Meta- trondhjemite Hornblende K/Ar 90.7 5 All locations from this source are approximate generalities. Meta-trondhjemite, inclusion in serpentinite mélange from north of San Antonio del Sur, Guantanamo Province. Reported age was 91 Ma on hornblende and 158 Ma on plagioclase, both recalculated here based on reported analytical data. Somin and others, 1992 Plagioclase K/Ar 157 15 D331-1M 20.0942 -74.765 Meta- trondhjemite Paragonite K/Ar 84.0 4 All locations from this source are approximate generalities. Metatrondhjemite, inclusion in serpentinite mélange from north of San Antonio del Sur, Guantanamo Province. Reported age was 87 Ma, recalculated here based on reported analytical data. Somin and others, 1992 3 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued D331-3M 20.0942 -74.765 Meta- trondhjemite Paragonite K/Ar 86.8 4 All locations from source are approximate generalities. Metatrondhjemite, inclusion in serpentinite mélange from north of San Antonio del Sur, Guantanamo Province. Reported age was 87 Ma, recalculated here based on reported analytical data. Somin and others, 1992 D331-5M 20.0942 -74.765 Amphibolite Hornblende K/Ar 116.1 9 All locations from source are approximate generalities. Amphibolite, inclusion in serpentinite mélange from north of San Antonio del Sur, Guantanamo Province. Reported age was 116 Ma, recalculated here based on reported analytical data. Somin and others, 1992 D336-6 20.0942 -74.765 Pegmatite Muscovite K/Ar 122 5 All locations from source are approximate generalities. Pegmatite inclusion in serpentinite mélange from Alto de Corea, Sierra del Cristal. Reported age was 122 Ma, recalculated here based on reported analytical data. Somin and others, 1992 CU22 20.1028 -74.6825 Trondhjemite Zircon U/Pb SHRIMP 112.8 1.1 Trondhjemite boulder from mélange. Location approximate, 9 grains analyzed. Lazaro and others, 2009 CV139a 20.1108 -74.5762 Amphibolite Amphibole 40/39 Plateau 82.67 0.84 Green amphibole. Location approximate. Plateau age based on 69.9% of gas. Plateau interpreted to reflect retrograde growth or cooling of retrograde amphibole. Lazaro and others, 2009 Amphibole 40/39 Integrated 96.5 0.8 Brown amphibole. Location approximate. Integrated age based on 93.9% of gas; no plateau determined. Interpreted as cooling of peak paragasitic amphibole. D322-1 20.1108 -74.5875 Schist Unknown, whole rock? K/Ar 61.7 5 All locations from source are approximate generalities. Mica-quartz schist, Purial series from Sierra del Purial north of Inias. Reported age was 75 Ma, recalculated here based on reported analytical data. Duplicated sample number in report, this is easternmost. Somin and others, 1992 CV227b 20.1125 -74.7193 Trondhjemite Amphibole 40/39 Integrated 94.7 1.1 Location approximate. Integrated age comprises 97.7% of gas. Final step, 41.6% of gas yielded 97.7±0.9 Ma, thought to reflect paragasitic amphibole age. Retrograde age was considered indeterminate. Lazaro and others, 2009 M-3 20.1128 -74.7370 Pegmatite Unknown, whole rock? K/Ar 116.8 10 All locations from source are approximate generalities. Mica-quartz schist, Cangre belt. 15 km east of Guane. Reported age was 116 Ma, recalculated here based on reported analytical data. Doubt it was actually muscovite, contained less than 1% K2O. Somin and others, 1992 CV228c 20.1133 -74.7195 Trondhjemite Amphibole 40/39 Integrated 85.7 1.5 Location approximate. Integrated age based on 67.9% of gas, final step yielded 105.5±1.9 Ma, 29% of gas. Interpretation suggests older age reflects paragasitic amphibole and integrated age reflects retrograde amphibole. Lazaro and others, 2009 GJ-258a 20.1138 -74.3084 Garnet Amphibolite Hornblende 40/39 Plateau 78.24 1.88 4 of 5 steps, (2 to 5), normal isochron 78.31±1.84 Ma, inverse isochron 78.4±1.62 Ma, MSWD = 0.15, 40Ar/36Ar intercept 256.4±71.0. Lazaro and others, 2015 GJ-259a 20.1151 -74.3103 Garnet Amphibolite Hornblende 40/39 Plateau 76.55 2.03 4 steps (3 to 6), MSWD = 0.76, 94.8% of 39Ar released, normal isochron age 78.57±2.03, inverse isochron age 77.62±1.78, 40Ar/36Ar intercept at 188.1±69.3. Lazaro and others, 2015 OFT-146g 20.1258 -74.3125 Amphibolite Amphibole 40/39 Plateau 123.2 2.2 Very crude estimate of location. Terrible map in publication. Apparent isochron age is 119±3.1 Ma, MSWD = 1.5, initial 40Ar/36Ar = 276.4±2.9. Lazaro and others, 2016 CV230b 20.1363 -74.7195 Amphibolite Amphibole 40/39 Integrated 90.6 1.1 Interpretation reflects mixing of primary and retrograde amphibole. Combined integrated age is 90.6±1.1 Ma using 97.5% of gas. Further interpretation suggests 86.9±0.9 Ma for retrograde amphibole (71.4% gas) and 100.6±1.8 for paragasitic amphibole. Lazaro and others, 2009 GJ-9 20.1388 -74.3114 Amphibolite Amphibole 40/39 Integrated 80.70 7.58 3 of 4 steps (2 to 4), integrated age, no plateau, 99.3% 39Ar. Lazaro and others, 2015 Unknown 20.2043 -74.4147 Amphibolite Whole rock K/Ar 60.6 5 Sierra del Purial; amphibolite complex. Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 20.2043 -74.4147 Amphibolite Whole rock K/Ar 63.5 0 Sierra del Purial; amphibolite complex. Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) CV53f 20.2885 -74.7103 Trondhjemite Amphibole 40/39 Integrated 94.8 2.3 Location approximate. Integrated age based on 97.4% of gas, reflecting mean age of magmatic and retrograde amphibole. Later steps 9 and 10 yielded 103.6±2.6 Ma, 42.2% of gas. Earlier step, 7, yielded 87.1±0.9 Ma (42.8% gas). Interpretation suggests older age reflects paragasitic amphibole and younger age reflects retrograde amphibole. Lazaro and others, 2009 D337 20.4264 -75.8608 Schist Unknown, whole rock? K/Ar 100.1 12 All locations from source are approximate generalities. Mica-quartz schist inclusion in serpentinite mélange from Alto de Corea, Sierra del Cristal. Reported age was 101 Ma, recalculated here based on reported analytical data. Somin and others, 1992 D339 20.4264 -75.8608 Pegmatite Muscovite K/Ar 93.3 4 All locations from source are approximate generalities. Pegmatite inclusion in serpentinite mélange from Alto de Corea, Sierra del Cristal. Reported age was 96 Ma, recalculated here based on reported analytical data. Somin and others, 1992 4 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued D350 20.4264 -75.8608 Schist Unknown, whole rock? K/Ar 65.0 7 All locations from source are approximate generalities. Mica-quartz schist inclusion in serpentinite mélange from Alto de Corea, Sierra del Cristal. Reported age was 66 Ma, recalculated here based on reported analytical data. Somin and others, 1992 Meyerhoff_3 20.5097 -75.5373 Pegmatite Whole rock K/Ar 116 11.6 20 km south of Nicaro, northern Oriente Province. Latitude and longitude approximate. Hauterivian (Early Cretaceous). Pegmatite dike cuts metamorphic rocks of Jurassic(?) age according to Adamovich and Chejovich (1964). Age recalculated with constants of Steiger and Jager (1977). Meyerhoff and others, 1969 GM206 20.5357 -79.7358 Amphibolite Whole rock K/Ar 59.4 12 Albite garnet amphibolite. Complejos de inclusiones en serpentinita y en zonas de mélange; Zona de mélange de Rancho Veloz. anfibolita ganaffera [Complex of inclusions in serpentinite and mélange zones of Rancho Veloz, northern Villa Clara Province]. All locations from sources are approximate generalities. Reported age 60 Ma, recalculated from analytical data. Somin and Millán, 1977 (in Spanish); Somin and others, 1992 GM203-3 20.5357 -79.7357 Amphibolite Whole rock K/Ar 59.7 12 Albite garnet amphibolite. Complejos de inclusiones en serpentinita y en zonas de mélange; Zona de mélange de Rancho Veloz. anfibolita ganaffera [Complexes of inclusions in serpentinite and mélange zones of Rancho Veloz, northern Villa Clara Province] Location not reported, coordinates here inferred. Reported age 60 Ma, recalculated from analytical data. Somin and Millán, 1977 (in Spanish) LB 204 20.607 -75.734 Gabbro Amphibole K/Ar 88.6 3.5 Gabbroic dike cutting peridotite. Marchesi, 2006 C-00-18 20.883 -76.733 Granodiorite Biotite 40/39 Plateau 72.9 0.2 Macizo Majibacoa, coarse grained. Hall and others, 2004 Biotite 40/39 Plateau 73.1 0.1 Hornblende 40/39 Plateau 73.1 0.6 Hornblende 40/39 Plateau 79.9 0.5 C-00-09 21.071 -77.423 Granodiorite Hornblende 40/39 Plateau 74.2 1.4 La Union, strongly porphyritic with phenocrysts of hornblende, plagioclase and altered pyroxene? Hall and others, 2004 Hornblende 40/39 Plateau 75.6 2.1 C-00-17 21.131 -77.318 Granodiorite Hornblende 40/39 Plateau 72.9 1.3 Pueblo Nuevo, coarse grained to seriate. Hall and others, 2004 Hornblende 40/39 Plateau 73.8 0.6 C-00-03A 21.15 -77.397 Syenite K-feldspar 40/39 Total fusion 79.6 0.2 Palo Seco quarry, coarse grained. Hall and others, 2004 K-feldspar 40/39 Total fusion 79.8 0.3 Hornblende 40/39 Total fusion 96.1 0.9 Palo Seco quarry, coarse grained. P. Renne, written commun. cited in Hall and others (2004). Biotite 40/39 Total fusion 96.8 0.4 C-98-2 21.15 -77.397 Granodiorite Hornblende 40/39 Plateau 68.4 0.3 Palo Seco quarry, coarse grained. Hall and others, 2004 Hornblende 40/39 Plateau 68.9 0.9 Hornblende 40/39 Plateau 69.5 0.5 C-98-3 21.166 -77.379 Syenite Biotite 40/39 Total fusion 71.4 0.1 Small pits 0.5 km south of Deseada, coarse grained. Hall and others, 2004 Biotite 40/39 Total fusion 72.4 0.2 Biotite 40/39 Plateau 72.7 0.3 K-feldspar 40/39 Plateau 71.9 0.6 K-feldspar 40/39 Plateau 72.3 0.3 C-00-06 21.177 -77.437 Syenite Biotite 40/39 Total fusion 60.1 0.3 Las Piedras, coarse grained. Hall and others, 2004 Biotite 40/39 Plateau 65.8 0.6 C-00-11 21.187 -77.539 Basalt Whole rock 40/39 Integrated 73.7 0.5 Camujiro Formation, La Elisa. Total fusion age was 73.2±0.5 Ma, no plateau so integrated age calculated. Hall and others, 2004 Whole rock 40/39 Integrated 75.7 0.9 Camujiro Formation, La Elisa. Total fusion age was 75.0±0.9 Ma, no plateau so integrated age calculated. D-1a 21.1931 -77.3625 Porphyry Alunite 40/39 Plateau 82.0 0.3 Deseada prospect, alunite-quartz-rutile-diaspore-kaolinite replacing volcanic(?) rock. Approximate location. Kesler and others, 2004 D-1b Alunite 40/39 Total fusion 92.6 2.1 D-1c Alunite 40/39 Total fusion 84.7 0.2 D-1d Alunite 40/39 Total fusion 81.8 0.3 DES-2 21.1931 -77.3625 Porphyry K-feldspar 40/39 Plateau 75.2 0.9 Deseada prospect, feldspar porphyry. Approximate location. Kesler and others, 2004 5 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued C-00-10 21.204 -77.443 Granodiorite Hornblende 40/39 Plateau 72.8 0.9 La Caridad, moderately porphyritic with phenocrysts of hornblende, plagioclase and altered pyroxene? Hall and others, 2004 Hornblende 40/39 Plateau 74.2 0.8 C-00-41 21.209 -77.782 Basalt Whole rock 40/39 Integrated 71.3 0.2 Piragua Formation, Santa Clara. Total fusion age was 64.8±0.2 Ma, no plateau so integrated age calculated. Hall and others, 2004 Whole rock 40/39 Integrated 71.5 0.2 C-00-42 21.209 -77.782 Volcaniclastic rock Whole rock 40/39 Integrated 72.1 0.2 Piragua Formation, Santa Clara. Total fusion age was 71.0±0.2 Ma, no plateau so integrated age calculated. Hall and others, 2004 73.7 0.3 Piragua Formation, Santa Clara. Total fusion age was 72.8±0.3 Ma, no plateau so integrated age calculated. C-00-05B 21.22 -77.402 Granodiorite Hornblende 40/39 Total fusion 63.2 2.5 Las Marias, Maraguan facies, very coarse grained. Hall and others, 2004 Hornblende 40/39 Plateau 73.3 0.4 Hornblende 40/39 Plateau 73.6 0.2 Biotite 40/39 Total fusion 72.3 0.2 Biotite 40/39 Plateau 73.0 0.2 C-00-40 21.223 -77.779 Basalt Whole rock 40/39 Integrated 73.0 0.2 Piragua Formation, La Eugenia. Total fusion age was 72.8±0.2 Ma, no plateau so integrated age calculated. Hall and others, 2004 Whole rock 40/39 Integrated 74.1 0.2 Piragua Formation, La Eugenia. Total fusion age was 75.6±0.2 Ma, no plateau so integrated age calculated. C-00-13A 21.2372 -76.9958 Volcanic rock Illite 40/39 Total fusion 75.5 0.2 Approximate location. Dumanuecos deposit in Caobilla Formation. Retention age 81.2±0.2 Ma. Kesler and others, 2004 C-00-22 21.247 -77.876 Basalt Whole rock 40/39 Integrated 72.3 0.2 Camujiro Formation, La Union. Total fusion age was 67.7±0.2 Ma, no plateau so integrated age calculated. Hall and others, 2004 Whole rock 40/39 Plateau 73.0 0.2 Camujiro Formation, La Union. Total fusion age was 67.7±0.1 Ma, no plateau so integrated age calculated. C-00-23A 21.247 -78.07 Rhyolite Biotite 40/39 Plateau 74.8 0.5 La Sierra Formation, Siete Palmas. Hall and others, 2004 Biotite 40/39 Plateau 75.1 0.5 C-98-1 21.26 -77.475 Rhyolite Biotite 40/39 Plateau 71.5 0.8 La Sierra Formation, Las Margaritas. Hall and others, 2004 Biotite 40/39 Plateau 72.1 0.2 K-feldspar 40/39 Plateau 72.5 0.4 K-feldspar 40/39 Plateau 73.3 0.6 C-98-1x 21.26 -77.475 Rhyolite Biotite 40/39 Plateau 71.2 0.2 La Sierra Formation, Las Margaritas. Hall and others, 2004 Biotite 40/39 Plateau 71.6 0.2 Biotite 40/39 Plateau 72.0 0.5 C-98-4 21.26 -77.475 Rhyolite K-feldspar 40/39 Plateau 72.4 0.7 La Sierra Formation, Las Margaritas. Hall and others, 2004 K-feldspar 40/39 Plateau 73.4 0.6 K-feldspar 40/39 Plateau 75.6 0.8 CSE-22-36 21.2614 -77.4958 Quartz vein Adularia 40/39 Plateau 73.3 1.5 Jacinto deposit. Reported plateau for adularia was described as a plateau-like segment of high T fractions consisting of 42% of 39Ar released. The two sources, using essentially the same figure, show different locations for this site; neither provide useful coordinates and the geologic map and Google Earth were used to provide approximate coordinates based on Kesler and others (2004) paper. Hall and others, 2004; Kesler and others, 2004 Adularia 40/39 Total fusion 74.3 0.2 CSE-22-41 21.2614 -77.4958 Quartz vein Adularia 40/39 Plateau 69.8 0.4 Jacinto deposit. The two sources, using essentially the same figure, show different locations for this site; neither provide useful coordinates and the geologic map and Google Earth were used to provide approximate coordinates based on Kesler and others (2004) paper. Hall and others, 2004; Kesler and others, 2004 C-00-21-1 21.2628 -77.7986 Porphyry K-feldspar 40/39 Total fusion 86.8 0.3 Feldspar porphyry. Tres Antenas (Vidot) prospect; paper on maps transposes name with La Mina; approximate location estimated based on map; assumes map sample numbers are transposed. Single grain age. Kesler and others, 2004 C-00-21-2 21.2628 -77.7986 Porphyry K-feldspar 40/39 Total fusion 77.3 0.3 Feldspar porphyry. Tres Antenas (Vidot) prospect; paper on maps transposes name with La Mina; approximate location estimated based on map; assumes map sample numbers are transposed. Single grain age. Kesler and others, 2004 6 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued C-00-21B 21.2628 -77.7986 Porphyry Illite 40/39 Total fusion 82.0 0.2 Feldspar porphyry. Tres Antenas (Vidot) prospect; paper on maps transposes name with La Mina; approximate location estimated based on map; assumes map sample numbers are transposed. A so- called retention age was 82.6±0.2 Ma. Kesler and others, 2004 C-00-20 21.285 -77.779 Syenite Hornblende 40/39 Plateau 71.6 0.4 Jimbambay, coarse grained. Hall and others, 2004 Hornblende 40/39 Plateau 73.0 0.3 C-00-43a 21.2889 -77.7267 Greisen Muscovite 40/39 Plateau 74.7 0.2 La Mina prospect; paper on maps transposes name with Tres Antenas; approximate location estimated based on map; assumes map sample numbers are transposed. Coarse-grained muscovite and quartz. Kesler and others, 2004 C-00-43b Muscovite 40/39 Plateau 73.4 0.1 C-00-15 21.403 -77.208 Basalt Whole rock 40/39 Integrated 50.8 0.5 La Mulata Formation. Total fusion age was 50.0±0.5 Ma, integrated age calculated. Hall and others, 2004 Whole rock 40/39 Integrated 52.0 0.3 La Mulata Formation. Total fusion age was 50.6±0.3 Ma, integrated age calculated. Whole rock 40/39 Integrated 53.2 0.3 La Mulata Formation. Total fusion age was 52.2±0.3 Ma, integrated age calculated. B15-1 21.5697 -77.8900 Altered rock Whole rock K/Ar 63.7 7 All locations from this source are approximate generalities. Quartz of albite-micaceous rock, inclusions in serpentinite mélange. Sierra de los Organos. Reported age 66 Ma. Recalculated here based on reported analytical data. Somin and Millán, 1977; Somin and others, 1992 C-00-24A 21.6145 -78.1733 Volcanic rock Illite 40/39 Total fusion 77.9 0.5 Approximate location. Loma Urabo deposit in Caobilla Formation. Retention age 78.9±0.5 Ma. Kesler and others, 2004 C-00-24B 21.6145 -78.1733 Volcanic rock Muscovite 40/39 Plateau 78.6 0.2 Approximate location. Loma Urabo deposit in Caobilla Formation. Kesler and others, 2004 4386 21.6984 -82.6641 Schist Muscovite K/Ar 75.9 4 Muscovite schist, Isle of Pines, Habana Province. Latitude and longitude approximate. Senonian. Early event of Laramide orogeny? Original reported age was 78 Ma. Recalculated with modern constants. Two determinations were made and average was reported. Individual determinations were (recalculated) 74.3 and 77.5 Ma. Same as Meyerhoff's sample 5. Laverov and others, 1967; Meyerhoff and others, 1969 4387 21.6984 -82.6641 Schist Muscovite K/Ar 71.2 4 Muscovite schist, Isle of Pines, Habana Province. Latitude and longitude approximate. Senonian. Early event of Laramide orogeny? Original reported age was 73 Ma. Recalculated with modern constants. Two determinations were made and average was reported. Individual determinations were (recalculated) 69.9 and 73.2 Ma. Same as Meyerhoff's sample 6. Laverov and others, 1967; Meyerhoff and others, 1969 Meyerhoff_4 21.6984 -82.6641 Schist Muscovite K/Ar 74 2 Muscovite schist, Isle of Pines, Habana Province. Senonian (Late Cretaceous). Kuman and Gavilan (1965) erroneously reported 190-m.y. date (Khudoley, 1967a, p. 673, footnote 4; Khudoley, 1967b, p. 789, footnote 7). Dates from Isle of Pines probably reflect Laramide events. Latitude and longitude approximate. Age recalculated using constants of Steiger and Jager (1977). Kuman and Gavilan, 1965; Khudoley, 1967a,b; Meyerhoff and others, 1969 C-00-31A 21.7520 -78.5045 Volcanic rock Illite 40/39 79.8 0.4 Approximate location. El Pilar deposit in Caobilla Formation. Retention age 79.8±0.4 Ma. First step of analysis was lost, only retention age reported. Kesler and others, 2004 C-00-30B 21.8261 -78.5761 Volcanic rock Illite 40/39 Total fusion 76.7 0.2 Approximate location. San Nicolas deposit in Caobilla Formation. Retention age 80.5±0.2 Ma. Kesler and others, 2004 GME-322 21.8353 -79.6647 Eclogite Muscovite K/Ar 71.7 5 All locations from this source are approximate generalities. Apo-eclogite rock, Loma la Gloria Formation from south of Sancti Spiritus Mountains. Reported age was 71 Ma, recalculated here based on reported analytical data. Somin and others, 1992 F25-10 21.8547 -79.6397 Metabasite Paragonite K/Ar 68 2 All locations from this source are approximate generalities. Metabasite from complex of Escambray, Caracusey lithofacies; northeast of Sancti Spiritus Mountains. Age as reported, no analytical data reported. Somin and others, 1992 F50-7 21.8547 -79.6397 Eclogite Paragonite K/Ar 73 4 All locations from this source are approximate generalities. Eclogite from complex of Escambray, Caracusey lithofacies; northeast of Sancti Spiritus Mountains. Age as reported, no analytical data reported. Somin and others, 1992 Unknown 21.8594 -82.7542 Schist Muscovite K/Ar 53.7 3 Muscovite schist, Complejo carbonato - terrigeno, Isla de Pinos, Loma el Soldado [Carbonate complex - terrigenous, Isle of Pines, Loma el Soldado] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 21.8594 -82.7542 Greisen Muscovite K/Ar 64.5 4 Greisen vein, Complejo carbonato - terrigeno, Isla de Pinos, Presa del Medio-las Nuevas [Carbonate complex - terrigenous, Isle of Pines, New middle dam] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) 7 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued E42-A 21.8658 -79.5247 Pegmatite Muscovite K/Ar 96.4 4 All locations from this source are approximate generalities. Pegmatite vein in the area of the Yayabo Formation, northeast of Sancti Spiritus Mountains. Reported age was 85 Ma, recalculated here based on reported analytical data. Somin and others, 1992 ES-5 21.8658 -79.5247 Schist Hornblende K/Ar 42.3 5 All locations from this source are approximate generalities. Mica-hornblende schist, Yayabo Formation from northeast of Sancti Spiritus Mountains. Reported age was 43 Ma, recalculated here based on reported analytical data. Hornblende was only 0.44% K2O. Somin and others, 1992 PE2/15 21.8890 -79.4474 Monzodiorite Zircon U/Pb SHRIMP 83.1 0.8 Unfoliated monzodiorite from drill core located southwest of Sancti Spiritus. 6 grains analyzed. Rojas-Agramonte and others, 2011 Unknown 21.9030 -80.1501 Amphibolite Hornblende K/Ar 42.0 5 Complejo carbonato - terrigeno, Escambray extremo oriental, anfiolita micacea [Carbonate complex - terrigenous, east end Escambray] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 21.9030 -80.1501 Schist Muscovite K/Ar 58.6 3 Complejo carbonato - terrigeno, Escambray extremo oriental, muscovite calc-schist [Carbonate complex - terrigenous, east end Escambray] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 21.9030 -80.1501 Schist Muscovite K/Ar 59.6 4 Complejo carbonato - terrigeno, Escambray extremo oriental, muscovite calc-schist [Carbonate complex - terrigenous, east end Escambray] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 21.9030 -80.1501 Schist Muscovite K/Ar 64.5 4 Complejo carbonato - terrigeno, Escambray extremo oriental, muscovite calc-schist [Carbonate complex - terrigenous, east end Escambray] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) E37-6 21.9140 -79.4982 Gneiss Zircon U/Pb SHRIMP 92.8 0.7 Fresh, fine-grained, sheet-like meta-trondhjemite body as much as 1 m wide. 5 grains analyzed most of which were low in U and therefore accumulated little radiogenic Pb, which resulted in large errors in the 207Pb/235U and 207Pb/206Pb ratios. However, the 206Pb/238U ratios are precise, and the concordant results can be combined to a mean age of 92.8±0.7 Ma, the time of trondhjemite emplacement. Deformation in this rock must be younger than this age. Rojas-Agramonte and others, 2011 F25-10 21.9143 -79.6395 Metabasite Paragonite K/Ar 68 2 Escambray unit, approximate location. Hatten and others, 1988 C-00-29Ba 21.9208 -78.6739 Altered rock Alunite 40/39 Total fusion 76.6 0.3 Approximate location. Loma Carolina deposit in Caobilla Formation. Kesler and others, 2004 C-00-29Bb 76.6 0.3 F50-7 21.9267 -79.6593 Eclogite Paragonite K/Ar 73 4 Escambray unit, approximate location. Hatten and others, 1988 ATP-1 21.9364 -80.1533 Schist Muscovite K/Ar 59.4 3 All locations from this source are approximate generalities. Muscovite-calcite schist, Loma la Gloria Formation from Trinidad Mountains. Reported age was 60 Ma, recalculated here based on reported analytical data. Somin and others, 1992 CU116 21.9393 -79.5412 Amphibolite Zircon U/Pb SHRIMP 93.0 0.9 Foliated amphibolite exposed in the Yayabo River west of Sancti Spiritus. Only a few idiomorphic zircons recovered from this sample show oscillatory zoning in CL images. Six grains were analyzed and provided concordant results. Four of these are well grouped and define a mean 206Pb/238U age of 93.0±0.9 Ma, whereas two grains, optically indistinguishable from the others, are much older at 315±2 and 903±7 Ma and are interpreted as xenocrysts. Rojas-Agramonte and others, 2011 Zircon U/Pb SHRIMP 315 2 Zircon U/Pb SHRIMP 903 7 ASP-1 21.9417 -79.5822 Schist Muscovite K/Ar 59.3 4 All locations from this source are approximate generalities. Calcite-muscovite schist from complex of Escambray, Caracusey lithofacies; northeast of Sancti Spiritus Mountains. Reported age was 61 Ma, recalculated here based on reported analytical data. Somin and others, 1992 ASP-2 21.9417 -79.5822 Schist Muscovite K/Ar 66.4 4 All locations from this source are approximate generalities. Calcite-muscovite schist from complex of Escambray, Caracusey lithofacies; northeast of Sancti Spiritus Mountains. Reported age was 66 Ma, recalculated here based on reported analytical data. Somin and others, 1992 C57 21.9443 -79.4971 Quartz monzonite Unknown K/Ar 85 1 Poorly foliated quartz monzonite, drill core near Sancti Spiritus; Manicaraguan Batholith. Hatten and others, 1988; Rojas-Agramonte and others, 2011 Zircon U/Pb SHRIMP 87.2 1.2 Poorly foliated quartz monzonite, drill core near Sancti Spiritus; Manicaraguan Batholith. 6 grains analyzed. Rojas-Agramonte and others, 2011 TIMS Multigrain 93.0 10 Poorly foliated quartz monzonite, drill core near Sancti Spiritus; Manicaraguan Batholith. Bibikova and others, 1988; Rojas- Agramonte and others, 2011 8 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued C60 21.9609 -79.4967 Quartz monzonite Zircon TIMS Multigrain 89.3 0.45 Foliated quartz monzonite, drill core west of Sancti Spiritus; Manicaraguan Batholith. Two splits run, coarse and fine, yielding 89.4 Ma and 89.1 Ma, respectively, both with 0.45 error. Rojas-Agramonte and others, 2011 89.3 2 Foliated quartz monzonite, drill core west of Sancti Spiritus; Manicaraguan Batholith. Hatten and others, 1988; Rojas-Agramonte and others, 2011 7CF3A 21.9631 -80.1880 Greenschist Phengite 40/39 Total fusion 57.20 1.80 Approximate location derived from poor map. La Sierrita Nappe, metacarbonate. 7 grains averaged. Despaigne-Diaz and others, 2016 CU114 21.9683 -79.5045 Amphibolite Zircon U/Pb SHRIMP 93.5 1.0 Strongly deformed amphibolite derived from pyroclastic rock of dacitic composition from the Mabujina metavolcanic suite. 6 grains analyzed, 4 yielding 93.5±1.0 Ma and 2 inherited, rounded grains yielded 471±4 and 1,059±8 Ma. Rojas-Argamonte and others, 2011 471 4 1,059 8 F94 21.9748 -79.8560 Blueschist Glaucophane K/Ar 56 3 Escambray unit, approximate location. Hatten and others, 1988 Phengite K/Ar 66 1 F94-1 21.9748 -79.8560 Blueschist Phengite K/Ar 68 1 Escambray unit, approximate location. Hatten and others, 1988 Glaucophane K/Ar 210 13 LV69 21.9808 -79.7015 Eclogite Whole rock Rb/Sr 65.1 3.0 MSWD = 83. An age of 66.0±1.7 Ma (MSWD = 5.3); intercept at 0.705721±0.000046 is obtained when garnet analytical point is removed. Sancti Spiritus Dome, collected from eclogitic lens in serpentinite. Matrix is dominated by sodic-calcic amphibole and epidote. Minerals found in sample are garnet, sodic-calcic amphibole, omphacite, epidote, phengite, glaucophane, quartz, rutile, and apatite. Garnet is generally euhedral and often rimmed by chlorite. However, some unaltered rims display textural equilibrium with garnet, omphacite, phengite, and sodic-calcic amphibole. Garnet cores are rich in quartz, rutile, apatite, epidote, graphite, and blue-green amphibole inclusions. Locally, glaucophane is present at edge of garnet rimmed by chlorite, attesting to blueschist-facies overprint. Approximate location. Schneider and others, 2004 Barroisite 40/39 Plateau 69.1 1.3 Sancti Spiritus Dome, collected from eclogitic lens in serpentinite; 95.5% Ar release for barroisite and 93.0% of Ar released for phengite. Matrix is dominated by sodic-calcic amphibole and epidote. Minerals found in sample are garnet, sodic-calcic amphibole, omphacite, epidote, phengite, glaucophane, quartz, rutile, and apatite. Garnet is generally euhedral and often rimmed by chlorite. However, some unaltered rims display textural equilibrium with garnet, omphacite, phengite, and sodic-calcic amphibole. Garnet cores are rich in quartz, rutile, apatite, epidote, graphite, and blue- green amphibole inclusions. Locally, glaucophane is present at edge of garnet rimmed by chlorite, attesting to blueschist-facies overprint. Approximate location. Phengite 40/39 Plateau 69.3 0.6 CU16 21.9917 -79.6927 Eclogite Phengite 40/39 Plateau 71.0 0.7 99.2% of Ar released. Schneider and others, 2004 Paragonite 40/39 Total fusion 69.9 0.7 Paragonite grain from sample was mostly degassed in two steps because of its low K concentration; however, it did yield total gas age of 68.9±0.7. LV66 21.9917 -79.6927 Eclogite Isochron Rb/Sr 65 15 MSWD = 206. (Excluding garnet and clinopyroxene), isochron age is 69.7±0.8 Ma MSWD±0.49, (87Sr ⁄86Sr) ratio of 0.705511±0.000010. Garnet, omphacite, epidote, glaucophane, paragonite, phengite, quartz, rutile, and albite. Epidote and white mica define main foliation. Garnet occurs as (1) large porphyroblasts (1–3 mm) with inclusion-rich cores (inclusions of quartz, rutile, apatite and graphite) surrounded by inclusion-poor rims, and (2) inclusion-poor small neoblasts (100–25 µm). Large porphyroblasts are optically zoned with a darker core and appear to be in textural equilibrium with omphacite, epidote, and mica. Glaucophane is optically zoned suggesting three growth stages. There is a clear inner core, a dark outer core edged by omphacite and garnet, and a clear rim that includes omphacite and garnet. Epidote is present as inclusions in garnet and in matrix. Loma la Gloria Formation, approximate location. Schneider and others, 2004 LV66 21.9917 -79.6927 Eclogite Phengite 40/39 Plateau 68.2 0.6 Loma la Gloria Formation: 99.2% of Ar released. Spot fusion analyses on second grain gave ages between 72.2 and 66.6 Ma. Approximate location. Schneider and others, 2004 F94 21.9945 -79.9803 Altered rock Muscovite K/Ar 67.7 1 All locations from this source are approximate generalities. Winchite-garnet-albite rock, Algarrobo Formation from northeast of Trinidad Mountains. Ages recalculated based on reported analytical data. Second albite split was only 0.039% K2O; date is quite dubious. Somin and others, 1992 Amphibole K/Ar 69.1 2 Albite K/Ar 159.6 15 GME-81-3 21.9945 -79.9803 Blueschist Paragonite K/Ar 66.5 8 All locations from this source are approximate generalities. Glaucophane schist, Algarrobo Formation from northeast of Trinidad Mountains. Age recalculated based on reported analytical data. Somin and others, 1992 9 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued SM-47 22.0090 -80.2782 Greenschist Phengite 40/39 Total fusion 59.4 0.8 Approximate location derived from poor map. La Sierrita Nappe, carbonate mica schist. 7 of 11 grains averaged. Isochron reflects all 11 grains. Despaigne-Diaz and others, 2016 F89-1 22.0203 -79.9905 Eclogite Paragonite K/Ar 74 4 Escambray unit, approximate location. Hatten and others, 1988 Hornblende K/Ar 255 7 Zircon TIMS Multigrain 102 2 G-104 22.0217 -80.2768 Greenschist Phengite 40/39 Total fusion 58.01 1.1 Approximate location derived from poor map. La Sierrita Nappe, carbonate mica schist. 8 grains averaged. Despaigne-Diaz and others, 2016 G-103 22.0226 -80.2768 Greenschist Phengite 40/39 Total fusion 56.32 0.40 Approximate location derived from poor map. La Sierrita Nappe, calcschist. 13 grains averaged. Despaigne-Diaz and others, 2016 G-102 22.0260 -80.2737 Greenschist Phengite 40/39 Total fusion 56.7 1.84 Approximate location derived from poor map. La Sierrita Nappe, calcschist. 10 grains averaged. Despaigne-Diaz and others, 2016 G2057 22.0270 -79.4439 Pegmatite Isochron Rb/Sr 74 1 Approximate location of Yayabo Quarry based on Google Earth. Isochron age combining whole rock and fine-grained white mica. Interpreted as a cooling age. Initial ratio of 0.7046. Grafe and others, 2001 Isochron Rb/Sr 81.8 0.4 Isochron age combining whole rock, multiple phases of coarse-grained white mica, and an indeterminate phase. Interpreted as a crystallization age. Initial ratio of 0.7034. G2061 22.0270 -79.4439 Pegmatite Muscovite 40/39 Total fusion 72.2 0.6 Approximate location of Yayabo Quarry based on Google Earth. Interpreted as a cooling age (350 to 400 °C). Grafe and others, 2001 Isochron Rb/Sr 74.6 0.7 Isochron age combining whole rock, multiple phases of fine-grained white mica, and one phase of coarse-grained white mica. Interpreted as a metamorphic age. Initial ratio of 0.7051. Isochron Rb/Sr 80 1 Isochron age combining whole rock and one phase of coarse-grained white mica. Interpreted as a crystallization age. Initial ratio of 0.7039. J77 22.0277 -79.8185 Orthogneiss Biotite K/Ar 73 1 Meta-granitoid, orthogneiss, approximate location. Hatten and others, 1988 Hornblende K/Ar 84 3 SR-65 22.0309 -80.2543 Greenschist Phengite 40/39 Total fusion 37 7 Approximate location derived from poor map. La Sierrita Nappe, carbonate mica schist. 7 grains averaged. Considered spurious age, mixing S1 and S2 foliations. Despaigne-Diaz and others, 2016 SR-65b 22.0317 -80.2519 Greenschist Phengite 40/39 Total fusion 57.4 3 Approximate location derived from poor map. La Sierrita Nappe, carbonate mica schist. 9 grains averaged. Despaigne-Diaz and others, 2016 J66-1 22.0408 -79.8498 Orthogneiss Biotite K/Ar 70 1 Meta-granitoid, orthogneiss, approximate location. Hatten and others, 1988 Hornblende K/Ar 95 2 F66-1 22.0483 -79.8906 Metadiorite Zircon TIMS Multigrain 93.8 0.47 Metadiorite vein in amphibolite was collected 1.5 km NW of Guinıa de Miranda and some 200 m west of sample F68, also in the Jicaya River. Xenoliths of amphibolite occur with sharp contacts within the metadiorite, although schistosity seems common to both rocks. Two zircon fractions, one representing a coarse “tap” and one a fine “tap,” were analyzed by conventional TIMS technique and yielded identical 206Pb/238U ages of 94.1±0.47 and 93.5±0.47 Ma, respectively. This is structurally one of the youngest of the Rio Jicaya granitoids, since it cuts an older foliation in the intruded amphibolites. Rojas-Agramonte and others, 2011 J66-4 22.0498 -79.8335 Orthogneiss Biotite K/Ar 69 2 Meta-granitoid, orthogneiss, approximate location. Hatten and others, 1988 Hornblende K/Ar 78 3 J68-3 22.0527 -79.8528 Pegmatite Muscovite K/Ar 84 1 Undeformed pegmatite cutting amphibolite. Manicaragua unit, approximate location. Hatten and others, 1988 SM-45 22.0585 -80.2828 Greenschist Phengite 40/39 Total fusion 60.56 0.66 Approximate location derived from poor map. La Sierrita Nappe, carbonate mica schist. 6 grains averaged. Despaigne-Diaz and others, 2016 CU32 22.0483 -79.8433 Gneiss Zircon U/Pb SHRIMP 122.1 2.1 Massive but well-foliated trondhjemite, was collected in the Jicaya River just south of F77. The zircons are idiomorphic and stubby to long prismatic and show excellent magmatic zoning under CL. Eight grains were analyzed on SHRIMP II, and all analyses produced concordant results. Seven grains define a cluster with a mean 206Pb/238U age of 112.1±2.1 Ma, which we consider reflects the time of trondhjemite emplacement. One grain is significantly older and has a concordant 207Pb/206Pb age of 1045±17 Ma which we interpret as an inherited zircon xenocryst. Rojas-Agramonte and others, 2011 1,045 17 CU36503 22.0502 -79.845 Trondhjemite Zircon U/Pb SHRIMP 84.2 0.8 Gray-whitish, fine- to medium-grained trondhjemite (quartz-bearing hornblende diorite) collected near Guinıa de Miranda in the Jicaya River. 8 grains analyzed. Rojas-Agramonte and others, 2011 SM-47 22.05968 -80.2782 Greenschist Phengite 40/39 Total fusion 56.8 1.1 Approximate location derived from poor map. La Sierrita Nappe, carbonate mica schist. 4 of 11 grains averaged. Isochron reflects all 11 grains. Despaigne-Diaz and others, 2016 10 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued F012 22.06228 -79.8855 Granodiorite White mica 40/39 Total fusion 73.8 0.5 Approximate location based on Google Earth. Fine-grained white mica, interpreted as cooling age, 350 to 400 °C. Grafe and others, 2001 Isochron Rb/Sr 82.1 0.6 Isochron age based on plagioclase, whole rock, and multiple phases of white mica. Interpreted as metamorphic age. Initial ratio 0.70335. F019 22.06228 -79.8855 Gneiss Muscovite Rb/Sr 73 3 Approximate location based on Google Earth. Biotite gneiss. Table 8 in Grafe and others (2001) reports this is a mineral age based on fine-grained white mica. Interpreted as cooling age. Table 6 in Grafe and others (2001) reports this is an isochron age combining plagioclase, whole rock, and biotite and gives an initial ratio of 0.70297. Grafe and others, 2001 S141 22.065 -79.8869 Pegmatite White mica Rb/Sr 73 1 Approximate location based on Google Earth. Mineral age based on fine-grained white mica from shear zones. Interpreted as a cooling age. Initial ratio 0.70336. Grafe and others, 2001 Isochron Rb/Sr 84.9 0.9 Isochron age based on contributions from whole rock, fine-grained white mica, and one phase of coarse-grained white mica. Interpreted to be metamorphic age. Initial ratio 0.70334. Isochron Rb/Sr 87.6 0.4 Isochron age based on contributions from whole rock and multiple phases of coarse white mica. Interpreted to be crystallization age. Initial ratio 0.70334. F68 22.0653 -79.8867 Orthogneiss Zircon U/Pb 110 10 Trondhjemitic orthogneiss. Earliest phase of magmatism. Bibikova and others, 1988; Rojas- Agramonte and others, 2011 F68 22.0653 -79.8867 Orthogneiss Zircon U/Pb SHRIMP 132.9 1.4 Trondhjemitic orthogneiss, 6 grains. Earliest phase of magmatism. Rojas-Agramonte and others, 2011 F68 22.0653 -79.8867 Orthogneiss Zircon TIMS Multigrain 133.0 2.0 Trondhjemitic orthogneiss. Earliest phase of magmatism. Rojas-Agramonte and others, 2011 F77 22.0654 -79.8904 Gneiss Zircon U/Pb 110 15 Age reported here is that determined by Bibikova and others (1988). Using conventional TIMS techniques, Bibikova and others (1988) analyzed one multigrain zircon fraction from the same sample and reported a 206Pb/238U age of 108±15 Ma. They combined this analysis with data for another multigrain fraction from nearby sample F77 (206Pb/238U age of 115±10 Ma) and reported a mean age of 110±15 Ma for both samples, which is cited in the literature as representing Mabujina granitoid magmatism (e.g., Millán 1996; Sukar and Perez 1997). However, a plot in a concordia diagram of the two samples analyzed by Bibikova and others (1988) shows these analyses to be strongly discordant, and in such cases 206Pb/238U ages are not geologically meaningful. The discordancy may partly be due to Pb loss and/or inheritance, depending on the balance between these two parameters. Sample collected in the Jicaya River some 2 km east of Guinıa de Miranda village. Bibikova and others, 1988; Rojas- Agramonte and others, 2011 F77 22.0654 -79.8904 Gneiss Zircon U/Pb Multigrain 123.9 0.62 Tonalitic gneiss, bulk sample. Collected in the Jicaya River some 2 km east of Guinıa de Miranda village; relict magmatic features are less clear than in above cases. A bulk fraction of this sample was analyzed conventionally in Santa Barbara and provided a 206Pb/238U age of 123.9±0.62 Ma, whereas inheritance is clearly indicated by a 207Pb/206Pb age of 225±8 Ma for this sample. Rojas-Agramonte and others, 2011 F009 22.0661 -79.8849 Pegmatite Isochron Rb/Sr 86.2 0.5 Approximate location based on Google Earth. Isochron age based on coarse-grained feldspar, whole rock, and multiple phases of coarse-grained white mica. Initial ratio 0.70342. Grafe and others, 2001 S157 22.0747 -79.9761 Pegmatite Isochron Rb/Sr 84.4 4 Approximate location of Road Manicaragua site based on Google Earth. Isochron age combining feldspar, whole rock, and white mica. Interpreted as a mixing of crystallization and metamorphic age. Initial ratio of 0.70351. Grafe and others, 2001 PM<C-4 22.0842 -80.0183 Amphibolite Whole rock K/Ar 52 1 Amphibolite, approximate location. Hatten and others, 1988 CU36005 22.0918 -79.9191 Tonalite Zircon U/Pb SHRIMP 87.0 0.6 Unfoliated gray biotite-hornblende tonalite collected from a roadcut 8.2 km south of Manicaragua, on the road to Fomento. 9 grains analyzed. Rojas-Agramonte and others, 2011 Meyerhoff_2 22.0985 -79.9879 Granodiorite Whole rock K/Ar 176 17.6 Near Manicaragua, southern Las Villas Province, north side of Sierra de Trinidad. Early Jurassic on Harland and others (1964) scale. Khudoley was skeptical of validity of this date. Hatten and others (1958, unpublished Cuban government report) believed that this is a middle Cretaceous intrusive. Meyerhoff believed that it may be late Paleozoic. Khudoley believed that the pluton may be Late Jurassic, but more probably is middle Cretaceous. Latitude and longitude approximate. Age recalculated with constants of Steiger and Jager (1977). Meyerhoff and others, 1969 CU36517 22.1022 -79.9187 Diorite Zircon U/Pb SHRIMP 88.7 0.7 Altered, unfoliated diorite collected in the El Marino River some 7 km southeast of Manicaragua, near the road from Manicaragua to Guinıa de Miranda. 5 grains analyzed. Rojas-Agramonte and others, 2011 CU204 22.1106 -79.2351 Trondhjemite Zircon U/Pb SHRIMP 76.6 0.4 Tres Guanos, 8 grains. Rojas-Agramonte and others, 2010 268.8 1.4 Tres Guanos, 1 grain. 11 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued PG-1 22.1158 -79.9593 Amphibolite Hornblende K/Ar 77 8 Amphibolite, approximate location. Hatten and others, 1988 Meyerhoff_1 22.1191 -79.2171 Quartz monzonite Biotite K/Ar 62.5 1.9 700 m S. 12° W. of Tres Guanos, Las Villas Province, at east end of Jarahueca fenster; in stream bed along road. Reported erroneously by Meyerhoff and Hatten (1968) as 67 Ma and by Khudoley (1967b) as 57 Ma. Date believed to be from secondary biotite formed during Laramide orogeny. Hatten and others (1958, unpublished Cuban government report) believed that pluton is a late Paleozoic intrusion. Khudoley (1967a,b) believed that it is Late Jurassic. Area of outcrop is overlain by Neocomian to Aptian rocks. Location approximate. Age recalculated with constants of Steiger and Jager (1977). Khudoley, 1967a,b; Meyerhoff and others, 1969 CU202 22.1194 -79.2251 Trondhjemite Zircon U/Pb SHRIMP 71.1 0.4 Tres Guanos, 7 grains. Rojas-Agramonte and others, 2010 536 3 Tres Guanos, 1 grain. F60-2 22.1205 -79.9968 Orthogneiss Biotite K/Ar 73 2 Meta-granitoid, orthogneiss, approximate location. Hatten and others, 1988 Hornblende K/Ar 73 2 CU6 22.1594 -79.9790 Tonalite Zircon U/Pb SHRIMP 87.4 1.3 Weakly foliated, medium-grained, hornblende-bearing tonalite collected below bridge over the Arimao River in town of Manicaragua. 6 grains analyzed. Rojas-Agramonte and others, 2011 CU12 22.3 -79.9583 Trondhjemite Zircon U/Pb SHRIMP 85.9 0.6 Collected from about 1-m3-sized fresh block of undeformed trondhjemite lying near road from Santa Clara to Manicaragua in area of Cerro El Chivo, close to National Highway, 9 grains dated. Rojas-Agramonte and others, 2010 CU180 22.3648 -79.6411 Tonalite Zircon U/Pb SHRIMP 74.8 0.7 San Andres body, Las Bocas Group, 7 grains. Rojas-Agramonte and others, 2010 CU181 22.3648 -79.6411 Granite Zircon U/Pb SHRIMP 76.3 0.5 San Andres body, Las Bocas Group, 7 grains. Rojas-Agramonte and others, 2010 82-72 22.4808 -83.9220 Blueschist White mica K/Ar 113.1 5 All locations from this source are approximate generalities. Garnet-glaucophane rock, inclusions in serpentinite mélange. Sierra de los Organos. Reported age 113 Ma. Recalculated here based on reported analytical data. Somin and others, 1992 Unknown 22.5055 -83.5905 Gneiss Muscovite K/Ar 53.7 6 Complejo de gneis del Guayabo, Noroeste de Pinar del Rio, Sur de Falla Pinar [Complex of Gneiss del Guayabo, Northwest of Pinar del Rio, South of Falla Pinar] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.5055 -83.5905 Gneiss Muscovite K/Ar 69.4 3 Complejo de gneis del Guayabo, Noroeste de Pinar del Rio, Sur de Falla Pinar [Complex of Gneiss del Guayabo, Northwest of Pinar del Rio, South of Falla Pinar] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.5055 -83.5905 Gneiss Muscovite K/Ar 72.3 1.4 Complejo de gneis del Guayabo, Noroeste de Pinar del Rio, Sur de Falla Pinar [Complex of Gneiss del Guayabo, Northwest of Pinar del Rio, South of Falla Pinar] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Western constants were in use. Somin and Millán, 1977 (in Spanish) D570E 22.5483 -79.8686 Altered rock Unknown K/Ar 88.5 9 All locations from this source are approximate generalities. Apo-eclogite garnet-hornblende rock, inclusions in serpentinite mélange. Near Santo Domingo, northern Villa Clara Province. Reported age 89 Ma. Recalculated here based on reported analytical data. Somin and others, 1992 Unknown 22.5961 -79.8777 Gneiss Whole rock K/Ar 64.5 7 Complejos de inclusiones en serpentinita y en zonas de mélange; Sierra del Rosario. Metasomatic plagioclase gneiss [Complexes of inclusions in serpentinite and mélange zones; Sierra de los Organos] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.5961 -79.8777 Schist Whole rock K/Ar 125 5 Complejos de inclusiones en serpentinita y en zonas de mélange; Sierra del Rosario. Quartz- glaucophane schist [Complexes of inclusions in serpentinite and mélange zones; Sierra de los Organos] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) GM206 22.6672 -80.0331 Amphibolite Whole rock K/Ar 59.4 12 Albite-garnet amphibolite. Complejos de inclusiones en serpentinita y en zonas de melange; Sierra de Rancho Veloz. Anfibolita ganaffera [Complex of inclusions in serpentinite and melange zones de Rancho Veloz, northern Villa Clara Province]. All locations from sources are approximate generalities. Reported age was 60 Ma, recalculated from analytical data. Somin and Millán, 1977 (in Spanish); Somin and others, 1992 12 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued B73 22.77 -83.3714 Amphibolite Hornblende K/Ar 93.6 12 All locations from this source are approximate generalities. Garnet amphibolite, inclusions in serpentinite mélange. Sierra del Rosario. Reported age 93 Ma. Recalculated here based on reported analytical data. Somin and others, 1992 Unknown 22.8192 -83.3192 Amphibolite Whole rock K/Ar 72.3 10 Complejo anfibolitico, Faja que rodea al macizo de escambray (Girdle that surrounds Escambray massif); amphibolite complex. Location not reported, coordinates here inferred from geologic map. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.8192 -83.3192 Amphibolite Whole rock K/Ar 79.1 1.6 Complejo anfibolitico, Faja que rodea al macizo de escambray (Girdle that surrounds Escambray massif); amphibolite complex. Location not reported, coordinates here inferred from geologic map. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.8192 -83.3192 Amphibolite Whole rock K/Ar 85 1.8 Complejo anfibolitico, Faja que rodea al macizo de escambray (Girdle that surrounds Escambray massif); amphibolite complex. Location not reported, coordinates here inferred from geologic map. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.8192 -83.3192 Amphibolite Whole rock K/Ar 87 3 Complejo anfibolitico, Faja que rodea al macizo de escambray (Girdle that surrounds Escambray massif); amphibolite complex. Location not reported, coordinates here inferred from geologic map. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.8364 -80.1901 Eclogite Muscovite K/Ar 112.3 5 Complejos de inclusiones en serpentinita y en zonas de mélange; Sierra del Rosario. [Complexes of inclusions in serpentinite and mélange zones; Sierra de los Organos] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.8424 -83.3563 Amphibolite Whole rock K/Ar 29.3 2 Complejos de inclusiones en serpentinita y en zonas de mélange; Sierra del Rosario. anfibolita ganaffera [Complexes of inclusions in serpentinite and mélange zones; Sierra del Rosario] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.8424 -83.3563 Amphibolite Whole rock K/Ar 56.7 2 Complejos de inclusiones en serpentinita y en zonas de mélange; Sierra del Rosario. anfibolita ganaffera [Complexes of inclusions in serpentinite and mélange zones; Sierra del Rosario] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.8424 -83.3563 Amphibolite Hornblende K/Ar 92.8 12 Complejos de inclusiones en serpentinita y en zonas de mélange; Sierra del Rosario. anfibolita ganaffera [Complexes of inclusions in serpentinite and mélange zones; Sierra del Rosario] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.8424 -83.3563 Amphibolite Whole rock K/Ar ~103 Complejos de inclusiones en serpentinita y en zonas de mélange; Sierra del Rosario. [Complexes of inclusions in serpentinite and mélange zones; Sierra del Rosario] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) GM203-3 22.8929 -79.9312 Amphibolite Hornblende K/Ar 59.7 12 Albite-garnet amphibolite. Complejos de inclusiones en serpentinita y en zonas de mélange; Zona de mélange de Rancho Veloz. anfibolita ganaffera [Complexes of inclusions in serpentinite and mélange zones of Rancho Veloz, northern Villa Clara Province] Location not reported, coordinates here inferred. Reported age was 64 Ma, recalculated from analytical data. Somin and Millán, 1977 (in Spanish); Somin and others, 1992 F201 Zir 22.9021 -80.5683 Granite Zircon U/Pb Multigrain 172.5 Rio Cana Granite, 2 fractions, coarse and fine grained. Data reported here for the fine-grained fraction; coarse-grained fraction yielded: 206Pb/238U = 197.3±0.4 Ma, 207Pb/235U = 206.2±0.6 Ma, and 207Pb/206Pb = 309±3 Ma. No error reported. Renne and others, 1989 CUH-4 22.9094 -80.5733 Marble Phlogopite 40/39 Plateau 903.5 7.1 Calculated integrated age. No location provided. Renne and others, 1989 Unknown 22.9159 -80.5716 Granite Whole rock K/Ar 136.7 5 Granito de Sierra Morena (Rio Cana Granite) Location not reported, coordinates inferred from geologic map. Date recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish), 1981 (in Russian); Renne and others, 1989 13 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Cuba—Continued Unknown 22.9159 -80.5716 Granite Whole rock K/Ar 142 5 Granito de Sierra Morena (Rio Cana Granite) Location not reported, coordinates here inferred from geologic map. Date recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish), 1981 (in Russian); Renne and others, 1989 Unknown 22.9159 -80.5716 Granite Whole rock K/Ar 146.5 5 Granito de Sierra Morena (Rio Cana Granite) Location not reported, coordinates here inferred from geologic map. Date recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish), 1981 (in Russian); Renne and others, 1989 Unknown 22.9618 -80.6690 Marble Phlogopite K/Ar 884 25 Complejo de marmol de Sierra Morena, Suroeste de Sierra Morena Loc. Socorro [Marble Complex of Sierra Morena, Southwest of Sierra Morena Loc. Socorro] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Unknown 22.9618 -80.6690 Marble Phlogopite K/Ar 918 25 Complejo de marmol de Sierra Morena, Suroeste de Sierra Morena Loc. Socorro [Marble Complex of Sierra Morena, Southwest of Sierra Morena Loc. Socorro] Location not reported, coordinates here inferred. Age recalculated using constants of Steiger and Jager (1977) assuming old Russian constants were in use. Somin and Millán, 1977 (in Spanish) Dominican Republic RD-72-10 18.5569 -70.1444 Tonalite Biotite K/Ar 80.9 2.0 Medina stock. 3 km northwest of Medina (toward Madrigal) on Arroyo Sosua (about 0.25 km east of road). Essentially equigranular tonalite with slightly larger hornblende (19%); remainder is quartz (24%), plagioclase (40%), K-feldspar (2%), and biotite (14%). Low K2O biotite. Location from Kesler and others (1991) differs from Bowin (1975), which was the same as sample RD-72-02. Bowin, 1975; Kesler and others, 1991 RD-72-02 18.6028 -70.1583 Tonalite Hornblende K/Ar 80.9 2.0 Medina stock. 0.25 km east of bridge over Rio Haina on Madrigal-Medina Road. Equigranular medium-grained tonalite (33% quartz, 43% plagioclase, 6% K-feldspar, 11% hornblende, 6% biotite). Location from Bowin (1975). Low K2O biotite. Bowin, 1975; Kesler and others, 1991 Biotite K/Ar 80.9 2.0 6JE34B 18.673 -70.0093 Amphibolite Hornblende 40/39 Plateau 110.3 1.4 5 steps (7 to 11); MSWD = 0.36 (plateau), 0.29 (isochron); 70% of 39Ar released. Rio Verde complex. Blasto-mylonitic amphibolite collected at Balneario Ledesma outcrop. Protolith is locally preserved in low-strain domains developed in amphibolite and consists of gabbro having MORB geochemical characteristics and weak subduction signature. Escuder Viruete and others, 2010 6JE34D 18.673 -70.0093 Amphibolite Hornblende 40/39 Plateau 110.7 1.6 5 steps (6 to 10); MSWD = 0.33 (plateau), 0.34 (isochron); 73.2% of 39Ar released. Rio Verde complex. Sample is amphibolite with a strong fabric from Balneario Ledesma outcrop. Escuder Viruete and others, 2010 BA-2014-1 18.7084 -69.5091 Rhyolite Zircon U/Pb SHRIMP 118.1 2.6 Eight spot analyses of 6 grains yielded concordant 206Pb/238U ages that range from 122.7±1.9 to 112.8±2.1 Ma, with a weighted mean of 118.1±2.6 Ma; MSWD = 2.94. 207Pb/235U age = 120.5±5 Ma, MSWD = 3.43. Torró and others, 2017 2JE38 18.7897 -70.1375 Amphibolite Hornblende 40/39 Plateau 118.6 1.3 Rio Verde complex. Medium- to coarse-grained amphibolite with foliation defined by altering hornblende-rich and plagioclase-rich bands. Collected near Loma Caribe Peridotite. 4 steps (4 to –7), MSWD = 0.44, 76.8% of 39Ar released. Location coordinates based on Google Earth and geology; coordinates based on index map are incorrect and do not match geology or geography Escuder Viruete and others, 2010 RD-72-18 18.75 -70.3639 Tonalite Hornblende K/Ar 63.0 1.5 Unnamed foliated tonalite. About 1 km southwest of sample RD-72-14 along Rancho Arriba Road. Similar to sample RD-72-14 with about 5% hornblende. Kesler and others, 1991 RD-72-17 18.7528 -70.3556 Norite Biotite K/Ar 81 2 Jautia norite. 0.7 km west of eastern contact of Jautia norite on Rancho Arriba Road. Coarse-grained with quartz (28%), plagioclase (44%), hornblende (20%), and biotite (8%). Very low K2O biotite. Kesler and others, 1991 450 18.7667 -70.2667 Tonalite Muscovite K/Ar 69.7 Foliated tonalite pluton west of El Puerto. Elsewhere in paper Bowin (1975) also called sample muscovite trondhjemite. Bowin, 1975 RD-72-14 18.7667 -70.3292 Tonalite Biotite K/Ar 56 2 Unnamed foliated tonalite. 10 km south of Piedra Blanca on Rancho Arriba Road and 0.25 km east of road on unnamed arroyo. Foliated rock with biotite (6%), quartz (48%), plagioclase (43%), and epidote (2%). Kesler and others, 1991 BA-2014-7 18.7685 -69.5229 Plagiorhyolite Zircon U/Pb SHRIMP 115.6 1.1 Thirty-five spot analyses on zircon grains yielded concordant 206Pb/238U ages from 125.8±3.2 to 109.1±1.7 Ma, with weighed mean of 115.6±1.1 Ma, MSWD = 2.8. An inherited zircon yielded 206Pb/238U age of 277.4±3.4 Ma. Torró and others (2018) reported youngest zircon population age of 109.1±1.7 Ma. Torró and others, 2017, 2018 B92 18.7833 -70.3043 Schist Hornblende K/Ar 93.3 9.3 Duarte Formation amphibolite schist in contact metamorphic aureole around foliated tonalite pluton. Recalculated using constants of Steiger and Jager (1977). Adjusted longitude to better match geology. Bowin, 1975 14 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Dominican Republic—Continued 6JE93A 18.9118 -70.3347 Gabbro Zircon U/Pb 125.4 0.4 Foliated gabbro. Three concordant grains in 2 fractions. Location coordinates based on Google Earth and geology; coordinates based on index map are incorrect and do not match geology or geography. Escuder Viruete and others, 2010 BA-2014-2 18.7985 -69.5148 Plagiorhyolite Zircon U/Pb SHRIMP 117.2 1.0 Forty-two spot analyses on 34 zircon grains yielded concordant 206Pb/238U ages that range from 125.2±2.1 to 107.6±2.1 Ma, having weighed mean of 117.2±1 Ma, MSWD = 2.37. Torró and others, 2017 JM9304- 6272II 18.8078 -69.5722 Rhyodacite Zircon U/Pb Multigrain 116.0 0.8 Porphyritic dacite, intermediate-composition rhyodacite unit. Los Ranchos Formation. Escuder Viruete and others, 2006b BA-2014-4 18.808 -69.5147 Plagiorhyolite Zircon U/Pb SHRIMP 114.5 +2.7/-3.4 Only 9 U-Pb determinations on 6 distinctively scarce and small zircon grains could be obtained. Slightly discordant owing to common lead, defining a poor discordia with lower intercept age of 114.5+2.7,-3.4 Ma, MSWD = 1.1861. Spot analysis 206Pb/238U ages range from 121.2±2.0 to 110.9±3.6 Ma (common lead uncorrected), from 120.8±2.1 to 111.3±4.0 Ma (207Pb corrected), and from 121.9±2.1 to 113.1±2.6 Ma (208Pb corrected). Torró and others, 2017 BA-2014-5 18.8086 -69.5179 Plagiorhyolite Zircon U/Pb SHRIMP 113.4 1.6 Twenty-eight spot analyses on 22 zircon grains yielded ages from 123.4±4.0 to 106.5±2.6 Ma, having weighted mean of 113.4±1.6 Ma, MSWD = 1.88. Inherited zircon grain yielded 206Pb/238U age of 628.2±12.2 Ma. Torró and others (2018) report youngest zircon population age of 106.5±2.6 Ma Torró and others, 2017 DA-23-11-199 18.8122 -69.6210 Rhyolite Molybdenite Re/Os 112.6 0.4 Bayaguana: Dona Armanda deposit. Collected at a depth of 199.0 m. Torró and others, 2017 B27f 18.8365 -70.2802 Hornblendite Plagioclase K/Ar 130 6.5 Approximate location. Date recalculated using critical table based on constants of Steiger and Jager (1977). Error corrected from Kesler and others (1977); original report was percentage error, not in years. Bowin's location was 18°51'N and 70°20'W, which appears incorrect. Bowin, 1975; Kesler and others, 1977 HH9045- 6272I 18.8963 -69.525 Tonalite Hornblende 40/39 Plateau 109.8 2.2 3 steps (4 to –6), MSWD = 0.53, 60.3% of 39Ar released. Coarse- to medium-grained hornblende tonalite from outcrop isolated by Haitises limestone. Sample ID shown on map is HH9274-6272-IV. Escuder Viruete and others, 2006b JM9070- 6372IV 18.9040 -69.3222 Tonalite Hornblende 40/39 Plateau 85.1 7.9 9 steps (1 to 8), MSWD = 0.85, 99.98% of 39Ar released. Coarse-grained equigranular isotropic hornblende and biotite tonalite which constitutes facies of El Valle batholith. There is a discrepancy between this sources map and the published 1:350,000 Dominican Republic map; it is likely that the pluton is larger than that shown on the published map. Escuder Viruete and others, 2006b DR6 18.9230 -71.6347 Basanite Unknown, whole rock? K/Ar 1.1 0.5 1.988% K2O, 5.6% radiogenic Ar. San Juan volcanic field, approximate location. Shown as DR3 on map in report. Wadge and Wooden, 1982 EB9042 18.9263 -70.9196 Andesite Hornblende 40/39 Plateau 69.6 0.7 Biotite-bearing porphyritic late andesite in Arroyo Limón area. Sample yielded plateau age for biotite of 69.6±0.7 Ma for high temperature six steps (6 to 11) and 72.3% of 39Ar released. Inverse isochron age is 70.9±2.2 Ma. Data is reported, but only suggestion of location is Arroyo Limon area; location here is place holder, pending better data. Escuder Viruete and others, 2007a DDH220- 163.0a 18.9383 -70.1813 Layer Pyrite Re/Os 114 2 Moore deposit, Pueblo Viejo ore body. Kirk and others, 2014 DDH-177 18.9417 -70.1833 Vein Alunite 40/39 Total fusion 65.99 Pyrite-alunite vein at 205 m depth in DDH-177 at Pueblo Viejo. No error reported, appears to be about 0.75 to 1 Ma. Approximate location derived from Kesler and others (2005b). Kesler and others, 1981 APV11-36 18.9428 -70.1998 Quartz vein Molybdenite Re/Os 112.12 0.20 APV11-36, 38.5 m depth. UTM coordinates: 373666, 2094922 (zone 19), collar elevation: 211 m, azimuth: 51°, inclination: -65°. Nelson and others, 2015; Torró and others, 2017 APV11-39A 18.9428 -70.1998 Quartz vein Molybdenite Re/Os 112.02 0.14 APV11-39A, 530.15 to 532.70 m depth. UTM coordinates: 373633, 2095696 (zone 19), collar elevation: 374 m, azimuth: 315°, inclination: -70°. Nelson and others, 2015; Torró and others, 2017 APV11-40A 18.9428 -70.1998 Quartz vein Molybdenite Re/Os 111.47 0.12 APV11-40A, 210.75 to 212.25 m depth. UTM coordinates: 373432, 2094656 (zone 19), collar elevation: 232 m, azimuth: 40°, inclination: -70°. Nelson and others, 2015; Torró and others, 2017 DDH-170-210 18.9433 -70.185 Quartz porphyry Zircon U/Pb Multigrain 110.9 0.8 30 grains dated, 3 rejected, 4 others omitted from age calculation. Approximate location. Pueblo Viejo system, lower Los Ranchos Formation. Kesler and others, 2005a,b; Kirk and others, 2014 DDH-242-39 18.9433 -70.1817 Quartz porphyry Zircon U/Pb Multigrain 111.4 0.7 36 grains dated, 4 rejected. Lower Los Ranchos Formation. Approximate location. Kesler and others, 2005a; Kirk and others, 2014 DDH-240-183 18.945 -70.1833 Quartz porphyry Zircon U/Pb Multigrain 111.3 0.6 28 grains dated, 3 rejected. Lower Los Ranchos Formation. Approximate location. Kesler and others, 2005a; Kirk and others, 2014 DDH227-92a 18.9448 -70.1733 Vein Sphalerite Re/Os 120 2 Monte Negro deposit, Pueblo Viejo ore body. Kirk and others, 2014 DDH227-92b 18.9448 -70.1733 Vein Sphalerite Re/Os 119 2 Monte Negro deposit, Pueblo Viejo ore body. Kirk and others, 2014 DDH227-92c 18.9448 -70.1733 Vein Sphalerite Re/Os 116 2 Monte Negro deposit, Pueblo Viejo ore body. Kirk and others, 2014 15 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Dominican Republic—Continued DDH227-92d 18.9448 -70.1733 Vein Sphalerite Re/Os 120 3 Monte Negro deposit, Pueblo Viejo ore body. Kirk and others, 2014 DDH235- 20.2a 18.9453 -70.1708 Vein Sphalerite Re/Os 110 2 Monte Negro deposit, Pueblo Viejo ore body. Kirk and others, 2014 JM9176- 6272IV 18.9493 -69.9152 Quartz diorite Hornblende 40/39 Plateau 109.3 5.2 9 steps (1 to 8), MSWD = 0.65, 100% of 39Ar released. Coarse- to medium-grained isotropic hornblende quartz-diorite from the rim facies of the Cevicos batholith (Sabana Grande de Boya). Escuder Viruete and others, 2006b DDH197- 95.7a 18.9253 -70.1713 Vein Pyrite Re/Os 112 1 Monte Negro deposit, Pueblo Viejo ore body. Kirk and others, 2014 DDH197- 95.7b 18.9253 -70.1713 Vein Pyrite Re/Os 114 2 Monte Negro deposit, Pueblo Viejo ore body. Kirk and others, 2014 JM9274- 6372IV 18.9584 -69.3567 Microgabbro Hornblende 40/39 Plateau 106.0 5.1 9 steps (1 to 8), MSWD = 1.4, 99.99% of 39Ar released. Fine-grained microgabbro that crosscuts the hornblende and biotite facies of the El Valle batholith. There is a discrepancy between this sources map and the published 1:350,000 Dominican Republic map; it is likely that the pluton is larger than that shown on the published map. Escuder Viruete and others, 2006b RD-73-601 18.9979 -70.1343 Quartz diorite Zircon U/Pb Multigrain 112.9 0.9 35 grains dated, 3 rejected as inherited, 4 others omitted from age calculation as they were discordant. Approximate location. Cotui quartz diorite. Age may reflect two populations, 18 grains at 111.8±0.6 Ma and 8 grains at 116.1±0.5 Ma Kesler and others, 2005b; Kirk and others, 2014 95101-6172IV 19.0038 -70.1394 Tonalite Zircon U/Pb Multigrain 115.5 0.3 Unfoliated tonalite, Zambrana batholith (Hatillo sheet area). Location is not shown on map in paper and is outside primary study area. Estimated location based on geologic map. Escuder Viruete and others, 2006b PD04-109- 143.4 19.0042 -70.0972 Limestone Alunite 40/39 Total fusion 47.8 0.3 Pueblo Viejo; Monte Negro deposit; Hatillo limestone. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Samples PD04-109-143.4 and PD04-109-145.8 taken from same drill hole found along a deep northwest-southeast-trending core zone of alteration that connects Moore and Monte Negro deposits. Their age difference is almost 30 Ma. Arribas and others, 2011 PD04-109- 145.8 19.0042 -70.0972 Limestone Alunite 40/39 Total fusion 75.2 0.4 Pueblo Viejo; Monte Negro deposit; Hatillo limestone. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Samples PD04-109-143.4 and PD04-109-145.8 taken from same drill hole found along a deep northwest-southeast-trending core zone of alteration that connects Moore and Monte Negro deposits. Their age difference is almost 30 Ma. Arribas and others, 2011 RD-73-405a 19.011 -70.1872 Limestone Alunite 40/39 Total fusion 58.9 1.5 Pueblo Viejo; Loma la Cuaba deposit. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Sample was taken from a zone of argillic alteration collected along northwest-southeast-trending ridge that extends for about 300 m from summit of Loma la Cuaba toward Hatillo limestone. It lacks foliation and consists of enclaves containing coarse-grained (1 to 0.5 mm) alunite, diaspore, and iron-oxide pseudomorphs after pyrite. Arribas and others, 2011 RD-73-405b Alunite 40/39 Plateau 55.6 1.3 RD-73-405c Alunite 40/39 Plateau 69.0 3.7 RD-73-405d Alunite 40/39 Plateau 56.0 2.6 RD-73-395a 19.0114 -70.0197 Limestone Alunite 40/39 Plateau 66.1 4.6 Pueblo Viejo; Loma la Cuaba deposit. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Sample was taken from a zone of argillic alteration collected along northwest-southeast-trending ridge that extends for about 300 m from summit of Loma la Cuaba toward Hatillo limestone. Sample is strongly sheared parallel to regional trends owing to parallel alignment of fine-grained alunite crystals disseminated throughout rock. Arribas and others, 2011 RD-73-395b 40/39 Total fusion 52.0 2.9 RD-73-395c 40/39 Total fusion 61.0 0.3 RD-73-395e 40/39 Total fusion 71.2 0.7 328a 19.0167 -70.6167 Tonalite Hornblende K/Ar 88.2 2.7 Near center of El Rio batholith. Bowin, 1975 RD-73-407a 19.0286 -70.1919 Limestone Alunite 40/39 Plateau 47.3 0.3 Pueblo Viejo; Loma la Cuaba deposit. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Sample was taken from a zone of argillic alteration collected along northwest-southeast-trending ridge that extends for about 300 m from summit of Loma la Cuaba toward Hatillo limestone. Sample is strongly sheared and foliated parallel to regional trends owing to numerous, narrow shear zones containing pyrophyllite and alunite. Arribas and others, 2011 RD-73-407b 40/39 Plateau 53.4 0.4 RD-73-407d 40/39 Plateau 45.7 1.1 RD-73-407e 40/39 Plateau 50.0 2.2 RD-72-73 19.0547 -70.1833 Quartz keratophyre Zircon U/Pb Multigrain 116.9 0.9 36 grains dated, 4 rejected as inherited, 3 others omitted from age calculation. Approximate location. Quita Sueno quartz keratophyre, Los Ranchos Formation. Age may reflect two populations, 8 grains at 113.9±0.8 Ma and 21 grains at 118.6±0.5 Ma. Kesler and others, 2005b; Kirk and others, 2014 MJ9364- 5973II 19.0778 -71.0847 Andesite Hornblende 40/39 Plateau 88.6 1.8 Hornblende- and plagioclase-bearing high-Mg porphyritic andesitic dike, intrusive in lower volcanic sequence (Tireo Formation) in Lamedero area. For 7 steps (2 to 8), hornblende plateau age is for 98.7% of 39Ar released. Inverse isochron age is 89.5±5.6 Ma. Escuder Viruete and others, 2007a 16 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Dominican Republic—Continued MJ9364B- 5973II 19.0833 -71.1063 Andesite Zircon TIMS Multigrain 85.5 2.6 Hornblende- and plagioclase-bearing high-Mg porphyritic andesitic dike, intrusive in lower volcanic sequence (Tireo Formation) in Lamedero area. Four zircon populations, two concordant, two discordant. Age from concordant populations. Discordant grains yielded upper intercept of 2.2±1.3 Ga. Escuder Viruete and others, 2007a PD04-115-265 19.0868 -70.6436 Limestone Alunite 40/39 Plateau 73.0 1.1 Pueblo Viejo; Moore deposit; Hatillo limestone. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Alunite in samples forms disseminated, white- to light-pink, fine-grained (<0.5 mm) masses, veinlets, and breccia matrix. Gold averages 2 to 3 g/t. Samples PD04-115-265 and PD04-115-266 were taken from same drill hole found along a deep northwest-southeast-trending core zone of alteration that connects the Moore and Monte Negro deposits. Although these two samples were taken 1 m apart in the core, they are almost 30 Ma different in age. Analysis of alunite in Pueblo Viejo does not yield any solid mineralization data. Arribas and others, 2011 PD04-115-266 19.0868 -70.6436 Limestone Alunite 40/39 Plateau 42.1 1.1 Pueblo Viejo; Moore deposit; Hatillo limestone. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Alunite in samples forms disseminated, white- to light-pink, fine-grained (<0.5 mm) masses, veinlets, and breccia matrix. Gold averages 2 to 3 g/t. Samples PD04-115-265 and PD04-115-266 were taken from same drill hole found along a deep northwest-southeast-trending core zone of alteration that connects the Moore and Monte Negro deposits. Although these two samples were taken 1 m apart in the core, they are almost 30 Ma different in age. Analysis of alunite in Pueblo Viejo does not yield any solid mineralization data. Arribas and others, 2011 RD-72-49 19.1386 -70.6127 Hornblendite Plagioclase K/Ar 56.3 3.4 Approximate location described as just north of Jarabacoa in hornblendite adjacent to tonalite pluton. Date recalculated using constants of Steiger and Jager (1977). Kesler and others, 1977 GS9724 19.174 -71.51 Andesite K-feldspar 40/39 Plateau 66.8 0.47 High-Mg hornblende-phyric andesitic flow of upper sequence in Restauración area. Obtained plateau age from K-feldspar is 66.8±0.47 Ma for six steps (3–7) and 83.3% of 39Ar released. Inverse isochron age is 67.5±2.1 Ma. Hornblende yielded imprecise plateau age of 98±17 Ma (all steps). Escuder Viruete and others, 2007a Hornblende 40/39 Plateau 98 17 FC9026- 5973IV 19.1967 -71.2569 Tonalite Hornblende 40/39 Plateau 74.9 1.8 4 steps (3 to 7), MSWD = 0.42, 89.9% of 39Ar released. Medium- to coarse-grained, foliated hornblende sample from Loma del Tambor batholith in Jicome area. Escuder Viruete and others, 2006a, 2007a RD-72-45 19.2343 -70.9297 Tonalite Biotite K-Ar 33 2 EI Bao batholith. Approximate latitude and longitude determined from geologic map. About 18.2 km south on road from San Jose de las Matas to Mata Grande. Essentially equigranular tonalite with early hornblende, plagioclase, and quartz, and later plagioclase, quartz, and biotite. Consists of 26% quartz, 49% plagioclase, 21% hornblende, and 5% biotite. Low K2O biotite. Kesler and others, 1991 Hornblende K/Ar 68.4 0.9 5JE54 19.2595 -70.7649 Amphibolite Hornblende 40/39 Plateau 93.95 1.37 Plateau represents 7 steps, 92.5% of gas, MSWD = 0.52. Normal isochron = 94.45±5.2 Ma; inverse isochron = 92.4±8.4 Ma, MSWD = 0.52. Green-gray amphibolite with intense fabric, locally gneissic. Nematoblastic to blastomylonitic texture. Mineral assemblage composed of hornblende to actinolitic hornblende + plagioclase + epidote + white mica ± sphene ± quartz + Fe-Ti oxide. Clean, blocky to tabular, hornblende mineral separates range in size from 0.1 to 0.3 mm. Escuder Viruete and others, 2007b 5JE56 19.2595 -70.7649 Amphibolite Hornblende 40/39 Plateau 95.85 1.89 Plateau represents 7 steps, 75.7% of gas, MSWD = 1.00. Inverse isochron was 91.5±12.6 Ma, MSWD = 0.90. Green-gray to blue amphibolite with intense L-S fabric, defined by hornblende nematoblasts. Blastomylonitic texture. Mineral assemblage composed of hornblende to hornblende + plagioclase + epidote + sphene ± white mica ± quartz + Fe-Ti oxide. Clean, tabular, hornblende mineral separates range in size from 0.5 to 1.6 mm. Escuder Viruete and others, 2007b RD-72-46 19.271 -70.9465 Tonalite Biotite K/Ar 49 2 El Bao Batholith. About 0.3 km north of sample RD-72-45. Equigranular tonalite with 10% early hornblende, 5% late biotite, 23% quartz, and 55% plagioclase. Approximate latitude and longitude determined from geologic map. Low K2O biotite. Kesler and others, 1991 Hornblende K/Ar 70.5 0.8 FC9052- 5973IV 19.3250 -71.4979 Andesite Hornblende 40/39 Plateau 88.9 2.6 6 steps (5 to 10), MSWD = 0.6, 92.9% of 39Ar released. Hornblende- and plagioclase-phyric sample that intrudes and crosscuts sequence of metabasalt of Duarte Complex in Jicome area. Dike is apophysis of Loma de Cabrera complex in their southern intrusive contact. Location from author. Escuder Viruete and others, 2006a, 2007b FC9063- 5973IV 19.3256 -71.2093 Amphibolite Hornblende 40/39 Plateau 82.8 1.9 10 steps (1 to 9), MSWD = .46 (plateau) .30 (isochron), 99.99% of 39Ar released. Blastomylonitic S-L sample from branch of La Meseta shear zone deforming Loma Guazumito-Los Charamicor massif in Jicome area. Protolith was low-Ti island-arc tholeiitic basalt of Tireo Formation. Escuder Viruete and others, 2006a RD-72-29 19.3452 -71.406 Amphibolite Plagioclase K/Ar 125.5 1.8 Amphibolite, approximate location described as 5 km west of Los Almacigos on Dajabon Road. Date recalculated using constants of Steiger and Jager (1977). Based on available geology, the described location is unlikely as this is deep within pluton. Location is better fit with geologic map. Kesler and others, 1977 Hornblende K/Ar 126.1 1.8 17 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Dominican Republic—Continued JE9015- 5974III 19.3903 -71.4806 Tonalite Hornblende 40/39 Plateau 73.9 .48 Foliated coarse-grained hornblende-biotite sample from late magma in Loma de Cabrera complex (Santiago Rodriguez area) that intermingles with N. 70 E trending mafic dikes in Rio Inaje area. Hornblende plateau represents four steps (4 to 8), MSWD = 1.9, 63.0% of 39Ar released. Biotite plateau represents six steps (9 to 14), MSWD = 1.9 (plateau), 0.30 (isochron), 39.2% of 39Ar released. Escuder Viruete and others, 2006a Biotite 40/39 Plateau 76.8 .44 RD-72-34 19.3972 -71.6167 Tonalite Hornblende K/Ar 49.4 0.6 Loma de Cabrera batholith. About 2.5 km south of Loma de Cabrera on road to Restauración. Porphyritic tonalite with hornblende and plagioclase phenocrysts and quartz-plagioclase-K-feldspar groundmass. Approximately 27% quartz, 46% plagioclase, 4% K-feldspar, and 21% hornblende. Kesler and others, 1991 JE9075- 5974III 19.45 -71.333 Amphibolite Hornblende 40/39 Plateau 74 1.7 4 steps (4 to 7), 95% of 39Ar released. Sample with strong fabric from La Meseta shear zone in Santiago Rodriguez area. Mafic protolith was basalt of Duarte complex. Escuder Viruete and others, 2006a JE9083-5874II 19.45 -71.625 Gabbro Hornblende 40/39 Plateau 83.0 9.2 7 steps (2 to 8), MSWD = 1.4, 97.5% of 39Ar released. Fine-grained sample from Loma Chaucey massif in Loma de Cabrera area. Low potassium content and very little argon release. Escuder Viruete and others, 2006a FC9054- 5874II 19.4681 -71.65 Tonalite Hornblende 40/39 Plateau 87.9 2.5 Coarse-grained sample from facies of Loma de Cabrera batholith. Low potassium content. Three step plateau (3 to 5), most of the 39Ar (85.6% release) was released in two steps, MSWD = 1.01, Location approximate using map provided by article. Escuder Viruete and others, 2006a RD-72-30 19.4694 -71.5083 Tonalite Hornblende K/Ar 68.7 0.9 Loma de Cabrear batholith. About 9 km west of Almacigos on road from Santiago Rodriguez to Santiago de la Cruz. Equigranular mafic tonalite with 13% quartz, 38% plagioclase, and 48% hornblende. Kesler and others, 1991 MJ9141-5874I 19.5185 -71.514 Tonalite Hornblende 40/39 Plateau 83.5 0.8 Hornblende tonalite dike (Nb = 11 ppm) that intrudes and crosscuts Duarte Complex in Dajabón area. Very probably, dike is apophysis of Loma de Cabrera batholith. For 6 steps (4 to 9), obtained plateau age from hornblende is 83.5±0.8 Ma for 94.2% of 39Ar released. Inverse isochron age is 85.2±2.5 Ma. Escuder Viruete and others, 2006a, 2007a PU9024 19.537 -71.588 Rhyolite Zircon TIMS Multigrain 91.8 2.3 Porphyritic rhyolite, Tireo Formation. Four concordant zircon populations. Escuder Viruete and others, 2007a 25323 19.5382 -70.2458 Eclogite Zircon TIMS Multigrain 139.1 3.6 Rio San Juan Complex: Rb/Sr isochron on whole rock, garnet and phengite. Lu/Hf isochron on garnet, omphacite, amphibole, epidote, and whole rock. Approximate location. Two fractions of zircon dated yielding dates that are considered unreliable. Krebs and others, 2008; Escuder Viruete and others, 2013 Zircon TIMS Multigrain 137.8 1.9 Phengite 40/39 Plateau 73.42 0.74 Isochron Rb/Sr 74.7 0.5 Isochron Lu/Hf 103.6 2.7 PU9252 19.5422 -71.6346 Rhyodacite Hornblende 40/39 Plateau 91.8 2.3 Unfoliated rhyodacitic flow (adakite), spatially equivalent with rhyolite sample dated by U/Pb methods. For four steps (5 to 8), plateau age from hornblende is 91.8±2.3 Ma, representing 73.5% of 39Ar released. Inverse isochron age on 8 points is 92.2±10 Ma. Escuder Viruete and others, 2007a 25243 19.5505 -70.203 Blueschist Phengite 40/39 Plateau 73.85 0.79 Omphacite blueschist. Rio San Juan Complex, whole rock, phengite, and amphibole. Approximate location. Krebs and others, 2008 Isochron Rb/Sr 80.3 1.1 25356 19.596 -70.1587 Blueschist Isochron Rb/Sr 62.1 1.4 Jadeite blueschist Rio San Juan Complex, whole rock, garnet, and phengite. Approximate location. Krebs and others, 2008 PD04-114-175 19.6113 -70.0842 Limestone Alunite 40/39 Plateau 46.1 0.3 Pueblo Viejo; Moore deposit; Hatillo limestone. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Sample taken from a deep northwest-southeast trending core zone of alteration that connects the Moore and Monte Negro deposits. Arribas and others, 2011 6074I-JR9071 19.6221 -70.6909 Andesite Hornblende 40/39 Plateau 46.30 2.40 Pedro Garcia basement complex, andesite. Hernaiz Huerta and others, 2012 6074I-JR9073 19.6239 -70.6907 Gabbro Hornblende 40/39 Plateau 49.8 2.9 Pedro Garcia basement complex, gabbro-diorite. Sample location is possibly slightly too far to the northwest, depending on the apparent geology. Hernaiz Huerta and others, 2012 6074I- JR9229C 19.6247 -70.6908 Tonalite Hornblende 40/39 Plateau 47.26 0.59 Pedro Garcia basement complex, tonalite. Sample location is possibly slightly too far to the northwest, depending on the apparent geology. Hernaiz Huerta and others, 2012 PD04-24A- 102.1 19.645 -70.0903 Limestone Alunite 40/39 Plateau 74.2 0.9 Pueblo Viejo; Monte Negro deposit; Hatillo limestone. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Gold average is low (0.25–2 g/t). Samples PD04-24A-102.1 and PD04-24A-109.7 taken from same drill hole found along a deep northwest- southeast trending core zone of alteration that connects Moore and Monte Negro deposits. Arribas and others, 2011 18 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Dominican Republic—Continued PD04-24A- 109.7 19.645 -70.0903 Limestone Alunite 40/39 Total fusion 78.8 0.3 Pueblo Viejo; Monte Negro deposit; Hatillo limestone. Latitude and longitude are approximations using map provided and georeferenced using Google Earth. Gold average is low (0.25–2 g/t). Samples PD04-24A-102.1 and PD04-24A-109.7 taken from same drill hole found along a deep northwest- southeast trending core zone of alteration that connects Moore and Monte Negro deposits. Sample appears to show range of ages, from ~65 to ~90 Ma. Arribas and others, 2011 6075III- HH9128 19.6915 -70.9747 Basalt Hornblende 40/39 Plateau 49.7 0.5 Palma Picada basement complex. Porphyritic basalt. Location possibly too far north depending on quality of geologic mapping. Hernaiz Huerta and others, 2012 6075III- HH9126 19.7069 -70.975 Basalt Hornblende 40/39 Plateau 50.44 0.85 Palma Picada basement complex. Porphyritic basalt. Location possibly too far north depending on quality of geologic mapping. Hernaiz Huerta and others, 2012 5975II- FP9091 19.7489 -71.1616 Basalt Whole rock 40/39 Plateau 64.26 0.96 Palma Picada basement complex. Spillitized, brecciated basalt. Location possibly too far south depending on quality of geologic mapping. Hernaiz Huerta and others, 2012 6075III- HH9133 19.8024 -70.7755 Granite Biotite 40/39 Plateau 95.4 1.2 Puerto Plata basement complex, intrusion in Los Canos Formation; leucogranite. Hernaiz Huerta and others, 2012 6075III- HH9124 19.8121 -70.8061 Troctolite Hornblende 40/39 Plateau 55.0 8.0 Puerto Plata basement complex gabbro and gabbronorite; banded troctolite. Hernaiz Huerta and others, 2012 5975III- PU9697 19.8223 -71.3151 Rhyolite Xenocrysts U/Pb 122.7 0.3 El Cacheal basement complex. Location coordinates (19.8223°, 71.3151°) in paper are in error, corrected here based on geology and map in paper. Hernaiz Huerta and others, 2012 5975III- PU9697 19.8223 -71.3151 Rhyolite Zircon U/Pb 90.90 0.50 El Cacheal basement complex. Location coordinates (19.8223°, 71.3151°) in paper are in error, corrected here based on geology and map in paper. Hernaiz Huerta and others, 2012 6075II- JM9271 19.8352 -70.7719 Andesite Hornblende 40/39 Plateau 81.60 2.70 Puerto Plata basement Los Canos Formation; porphyritic andesite. Hernaiz Huerta and others, 2012 6075IV- JE9119B 19.8364 -70.7593 Gabbro Zircon U/Pb 126.1 0.3 Minimum age, based on single concordant fraction. Puerto Plata basement complex gabbro and gabbronorite unit. Hernaiz Huerta and others, 2012 6075II- JM9272B 19.8365 -70.7715 Andesite Hornblende 40/39 Isochron 81.90 5.80 Puerto Plata basement Los Canos Formation; porphyritic andesite. Normal isochron 81.90±5.80 Ma, inverse isochron 91±11 Ma. Hernaiz Huerta and others, 2012 DRN-12 21.8658 -79.5247 Blueschist White mica K/Ar 31.7 3 All locations from source are approximate generalities. Garnet-glaucophane rock, La Chiva complex of Samana, Samana Peninsula, Haiti. Reported age was 32 Ma, recalculated here based on reported analytical data. Description says Haiti but peninsula mentioned is in Dominican Republic. Somin and others, 1992 Haiti HA77-28 18.4000 -72.4250 Basalt Whole rock 40/39 Plateau 88.7 1.5 Dumisseau Formation, approximate location. Isochron age 96.2±5.6 Ma. Sinton and others, 1998 HA76-165 18.4000 -72.4250 Basalt Whole rock 40/39 Plateau 90.6 1.1 Dumisseau Formation, approximate location. Isochron age 92.2±1.1 Ma. Sinton and others, 1998 HA74-24 18.0000 -72.4250 Basalt Whole rock 40/39 Plateau 91.2 0.6 Dumisseau Formation, approximate location. Isochron age 91.1±1.3 Ma. Sinton and others, 1998 HA76-120 18.4000 -72.4250 Basalt Whole rock 40/39 Plateau 89.2 1.5 Dumisseau Formation, approximate location. Isochron age 90.0±4.9 Ma. Sinton and others, 1998 H2 18.8127 -72.0103 Nephelinite Unknown, whole rock? K/Ar 1.8 0.9 1.01% K2O; 5.3% radiogenic Ar. Thomazeau volcanic center; approximate location. Wadge and Wooden, 1982 LM01 19.2547 -71.7583 Rhyolite Zircon U/Pb 84.3 1.4 Average using 34 of 38 grains. Location is approximate, based on map in thesis, estimated UTM (zone 18) coordinates for drill hole LMDH07 collar were 2131300.0 Northing and 210050 Easting. Sample collected at depth between 111.50 and 130.05 m in drill hole. Pauca, 2014 MD-1333 19.5883 -71.9792 Quartz vein Molybdenite Re-Os 93.31 0.13 DDH-002, 194.6 m. Location approximate. Nelson and others, 2015 Terre-Neuve 19.6067 -72.7833 Quartz monzonite Biotite K/Ar 67.9 1.3 Approximate location, age recalculated using constant of Steiger and Jager (1977). Kesler and Fleck, 1967; Kesler, 1971 HH9124 19.8267 -70.795 Troctolite Hornblende 40/39 Plateau 55.0 8.1 Plateau age is 55.0±8.1 Ma (MSWD = 0.1) for 6 steps (2 to 7) and 69.9% of 39Ar released. Inverse isochron 55.5±9.6 Ma. Coarse-grained troctolite, from IM3 unit of Imbert Formation, collected in Arroyo Seco outcrop at Cerro de Gran Diablo. It contains igneous plagioclase and olivine, with minor orthopyroxene and clinopyroxene, and secondary hornblende. Escuder Viruete and others, 2016 19 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Haiti—Continued 6075II- JM9112 19.8333 -70.7425 Leucogabbro- norite Plagioclase 40/39 Plateau 35.1 8.1 Plateau age is 35.1±8.1 Ma (MSWD = 4.6) for 7 steps (3 to 10) and 96.0% of 39Ar released. Inverse isochron 34±13 Ma. Coarse-grained leucogabbro-norite, collected in quarry from Imbert Formation on road to Puerto Plata. It contains plagioclase, clinopyroxene and orthopyroxene, with minor olivine and spinel. Reported as sample 6075II-JM9112 by Hernaiz Huerta and others (2012) and slightly different age of 35.8. Location from Hernaiz Huerta and others (2012). Hernaiz Huerta and others, 2012; Escuder Viruete and others, 2016 10JE54 19.835 -70.744 Leucogabbro Plagioclase 40/39 Plateau 44.0 3.1 Plateau age is 44.03.1 Ma (MSWD = 1.2) for 7 steps (1–7) and 100.0% of 39Ar released. Inverse isochron was 42.8±5.3 Ma. Coarse-grained leucogabbro, collected in quarry from Imbert Formation on road to Puerto Plata. Microscopically, it displays layered adcumulate igneous texture, defined by variations in modal contents of plagioclase and clinopyroxene, with minor orthopyroxene, olivine, and spinel. Escuder Viruete and others, 2016 Jamaica AHBD07 18.0082 -76.6087 Granite Plagioclase 40/39 Total fusion 25.2 0.3 Cedar Valley, microgranite dike. Porphyritic rock with plagioclase feldspar, K-feldspar, hornblende, and quartz phenocrysts. Groundmass is composed of feldspar, amphibole, quartz, and opaque minerals. Approximate location. Hastie, 2007 AHBD10C 17.9483 -76.3320 Basalt Groundmass 40/39 Total fusion 150.5 1.9 Highly altered lava flow. Rock is aphyric and is composed of plagioclase feldspar, clinopyroxene, and opaque minerals. Rock is altered, and substantial serpentine and clay minerals are present. Hastie (2007) used an age of 88.5 Ma in his dissertation for this rock. Approximate location. Hastie, 2007 AHBD10D 40/39 Total fusion 113.8 1.3 SNC4 17.93 -76.5383 Felsite Whole rock K/Ar 38.3 1.1 Ness Castle felsite. Age thought to be too young. Felsite (dacite) cutting serpentinite along road southeast Ness Castle. Approximate location. Date recalculated using constants of Steiger and Jager (1977). Lewis and others, 1973 AHWG03A 17.9513 -76.6551 Rhyodacite 40/39 Plateau 52.98 0.52 Adakitic rhyodacite, Bito Quarry. MSWD = 0.47 for 61% 39Ar. Average age of samples AHWG03A and AHWG03B is 52.74±0.34 Ma, MSWD = 1.5. Altered massive lava flow. Rock is porphyritic with phenocrysts of plagioclase feldspar and K-feldspar, which are partially altered to sericite. Groundmass is composed of feldspars, quartz, and opaque minerals. Groundmass has been substantially replaced with sericite and clay minerals. Hastie and others, 2010 AHWG03B 17.9513 -76.6551 Rhyodacite 40/39 Plateau 52.56 0.44 Adakitic rhyodacite, Bito Quarry. MSWD = 1.09 for 64.7% 39Ar. Average age of samples AHWG03A and AHWG03B is 52.74±0.34 Ma, MSWD = 1.5. Altered massive lava flow. Rock is porphyritic with phenocrysts of plagioclase feldspar and K-feldspar, which are partially altered to sericite. Groundmass is composed of feldspars, quartz, and opaque minerals. Groundmass has been substantially replaced with sericite and clay minerals. Hastie and others, 2010 67 17.9612 -77.6087 Bauxite Zircon Fission-track 36.7 7.4 Graben bauxite, 3 of 6 grains; 45 fossil tracks, 54 induced tracks. Location approximate. Comer and others, 1980 Zircon Fission-track 41.4 5.9 Graben bauxite, 4 of 6 grains; 96 fossil tracks, 102 induced tracks. Location approximate. Zircon Fission-track 44.5 6.4 Graben bauxite, 5 of 6 grains; 98 fossil tracks, 97 induced tracks. Location approximate. Zircon Fission-track 45.4 8.1 Graben bauxite, 2 of 6 grains; 64 fossil tracks, 62 induced tracks. Location approximate. Zircon Fission-track 46.5 2.7 Graben bauxite, composite of 6 grains; 610 fossil tracks, 577 induced tracks. Location approximate. Zircon Fission-track 51.5 4.5 Graben bauxite, 6 of 6 grains; 287 fossil tracks, 245 induced tracks. Location approximate. Zircon Fission-track 51.7 17.0 Graben bauxite, 1 of 6 grains; 20 fossil tracks, 17 induced tracks. Location approximate. 227 17.9883 -77.6667 Schist Biotite K/Ar 49.9 1.3 Westphalia Schist, approximate location. Biotite, very low K2O. Date recalculated using constants of Steiger and Jager (1977). Lewis and others, 1973 481 17.9883 -77.6667 Schist Biotite K/Ar 54.1 1.4 Westphalia Schist, approximate location. Biotite, low K2O. Biotite and hornblende are discordant. Date recalculated using constants of Steiger and Jager (1977). Lewis and others, 1973 Hornblende K/Ar 78.2 2.1 71-2 18.0667 -77.15 Hornfels Biotite K/Ar 84.6 1.5 Hornfels associated with Ginger Ridge granodiorite. Approximate location. Date recalculated using constants of Steiger and Jager (1977). Lewis and others, 1973 Biotite K/Ar 84.8 1.6 27 18.0667 -77.1622 Granodiorite Hornblende K/Ar 48.2 1.8 Ginger Ridge granodiorite. Approximate location. Date recalculated using constants of Steiger and Jager (1977). Lewis and others, 1973 Whole rock K/Ar 74.3 2.0 Isochron 18.0667 -77.1622 Granodiorite Isochron K/Ar 87 9 Isochron of Ginger Ridge granodiorite and hornfels. Inferred by Lewis and others (1973) to better reflect age of emplacement. Approximate location. Date recalculated using constants of Steiger and Jager (1977). Based on other age determinations, the isochron is probably too old. Lewis and others, 1973 20 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Jamaica—Continued 54 18.0825 -77.514 Bauxite Zircon Fission-track 17.2 2.7 Plateau bauxite, 1 of 5 grains; 59 fossil tracks, 150 induced tracks. Location approximate. Comer and others, 1980 Zircon Fission-track 15.1 2.9 Plateau bauxite, 2 of 5 grains; 36 fossil tracks, 105 induced tracks. Zircon Fission-track 23.9 1.9 Plateau bauxite, 3 of 5 grains; 232 fossil tracks, 427 induced tracks. Zircon Fission-track 24.9 5.0 Plateau bauxite, 4 of 5 grains; 39 fossil tracks, 69 induced tracks. Zircon Fission-track 65.9 19.0 Plateau bauxite, 5 of 5 grains; 30 fossil tracks, 20 induced tracks. RM51 18.105 -77.36 Basalt Hornblende K/Ar 70.3 1.9 Basaltic dike rock. Approximate location. Date recalculated using constants of Steiger and Jager (1977). Lewis and others, 1973 CHUBB3 18.1097 -76.8995 Granodiorite Biotite Rb/Sr 64 5 Zion Hill Bridge. Approximate location determined using map in ArcGIS. K/Ar age recalculated using constants of Steiger and Jager (1977). Sphene determination may represent a Pb-alpha analysis, which are generally discredited. Chubb and Burke, 1963 Biotite K/Ar 66.7 5 Sphene U/Pb 64 5 AHAR02G 18.1137 -76.8963 Granodiorite Biotite 40/39 Plateau 64.3 0.53 Fresh intrusion with abundant xenoliths. Coarse-grained rock composed of plagioclase feldspar, K- feldspar, biotite mica, hornblende, quartz, and opaque minerals. Feldspars have been slightly altered to sericite. One sigma error reported. Hastie, 2007 AHAR02K Biotite 40/39 Total fusion 63.2 2.5 AHCI39 18.1264 -77.3868 Basaltic andesite Plagioclase 40/39 Plateau 80.3 0.5 Altered massive lava flow. Although rock is altered, it appears to be porphyritic. Phenocrysts, composed of plagioclase feldspar are partially altered to chlorite, clay minerals, and sericite. Groundmass is feldspar and opaque minerals, also replaced with clay minerals, chlorite, and sericite. Quartz and chlorite vein seen. Hastie and others (2013) reported 1 sigma error, MSWD = 0.65, 75% 39Ar in plateau. Hastie, 2007; Hastie and others, 2013 AHCI40 18.12634 -77.3868 Basaltic andesite Plagioclase 40/39 Plateau 80.1 0.8 No sample description nor location provided; location used here derived from sample AHCI39, which was 10 m south. 1 sigma error, MSWD = 0.83, 100% 39Ar in plateau. Hastie and others, 2013 CHUBB1 18.1347 -76.8308 Granodiorite Feldspar K/Ar 55.4 5 Hall Green locality. Approximate location determined using map in ArcGIS. Ages recalculated using constants of Steiger and Jager (1977). Chubb and Burke, 1963 AHAR14 18.1599 -76.8859 Andesite Plagioclase 40/39 Plateau 68.9 0.42 Altered massive lava flow. Rock is porphyritic with phenocrysts of plagioclase feldspar and amphibole. Groundmass is composed of plagioclase, amphibole, and opaque minerals. Rock is moderately altered with clay minerals, sericite, and Fe-oxyhydroxide staining. Hastie, 2007 AHAR16 18.1967 -76.8933 Andesite Whole rock Not reported 70.5 -- Altered massive lava flow. Method and error not reported. Hastie, 2007 CHUBB2 18.2127 -76.9258 Granodiorite Feldspar K/Ar 74.5 5 Troja locality. Approximate location determined using map in ArcGIS. Ages recalculated using constants of Steiger and Jager (1977). Chubb and Burke, 1963 Low 18.2167 -76.5854 Basalt Whole rock K/Ar 9.5 0.5 Alkaline basalt from uplifted submarine volcano at Low Layton on northeast coast of Jamaica. Approximate location. Wadge, 1982; Wadge and Wooden, 1982 A-1 18.2288 -77.0993 Bauxite Zircon Fission-track 10.7 2.7 Plateau bauxite, 3 of 6 grains; 19 fossil tracks, 78 induced tracks. Location approximate. Comer and others, 1980 Zircon Fission-track 13.1 2.3 Plateau bauxite, 6 of 6 grains; 43 fossil tracks, 145 induced tracks. Zircon Fission-track 24.3 2.5 Plateau bauxite, 1 of 6 grains; 141 fossil tracks, 256 induced tracks. Zircon Fission-track 49.4 9.1 Plateau bauxite, 2 of 6 grains; 63 fossil tracks, 56 induced tracks. Zircon Fission-track 55.9 8.7 Plateau bauxite, 4 of 6 grains; 94 fossil tracks, 74 induced tracks. R-8 18.3397 -77.1382 Terra rossa Zircon Fission-track 36.2 8.0 Terra rossa, 1 of 6 grains; 37 fossil tracks, 45 induced tracks. Location approximate. Comer and others, 1980 Zircon Fission-track 42.4 4.1 Terra rossa, 6 of 6 grains; 210 fossil tracks, 218 induced tracks. Zircon Fission-track 46.7 16.6 Terra rossa, 3 of 6 grains; 17 fossil tracks, 16 induced tracks. Zircon Fission-track 49.4 9.7 Terra rossa, 5 of 6 grains; 55 fossil tracks, 49 induced tracks. Zircon Fission-track 73.2 8.3 Terra rossa, 4 of 6 grains; 205 fossil tracks, 123 induced tracks. Zircon Fission-track 76.3 20.0 Terra rossa, 2 of 6 grains; 40 fossil tracks, 23 induced tracks. K-4 18.377 -77.4297 Bauxite Zircon Fission-track 19.6 6.8 Plateau bauxite, 1 of 6 grains; 12 fossil tracks, 27 induced tracks. Location approximate. Comer and others, 1980 Zircon Fission-track 20.5 7.0 Plateau bauxite, 4 of 6 grains; 13 fossil tracks, 28 induced tracks. Zircon Fission-track 27.0 10.0 Plateau bauxite, 5 of 6 grains; 11 fossil tracks, 18 induced tracks. Zircon Fission-track 37.0 6.4 Plateau bauxite, 2 of 6 grains; 62 fossil tracks, 74 induced tracks. 21 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Jamaica—Continued 72.3 18.4707 -77.4922 Bentonite Biotite K/Ar 8.6 0.6 Hydrobiotite from bentonite. Mean of 2 determinations. Location approximate. Comer and others, 1980 Zircon Fission-track 6.5 1.0 Zircon, 1 of 9 grains, 46 fossil tracks, 310 induced tracks. Zircon Fission-track 9.3 0.8 Zircon, 2 of 9 grains, 150 fossil tracks, 712 induced tracks. Zircon Fission-track 9.8 1.4 Zircon, 3 of 9 grains, 62 fossil tracks, 279 induced tracks. Zircon Fission-track 10.2 1.1 Zircon, 4 of 9 grains, 101 fossil tracks, 437 induced tracks. Zircon Fission-track 6.6 0.9 Zircon, 5 of 9 grains, 57 fossil tracks, 380 induced tracks. Zircon Fission-track 10.6 2.2 Zircon, 6 of 9 grains, 29 fossil tracks, 121 induced tracks. Zircon Fission-track 9.4 1.5 Zircon, 7 of 9 grains, 45 fossil tracks, 221 induced tracks. Zircon Fission-track 6.8 1.1 Zircon, 8 of 9 grains, 41 fossil tracks, 265 induced tracks. Zircon Fission-track 8.5 1.2 Zircon, 9 of 9 grains, 63 fossil tracks, 328 induced tracks. Zircon Fission-track 8.6 0.4 Zircon, composite of 9 grains, 594 fossil tracks, 3053 induced tracks. Puerto Rico 43-2 18.0014 -67.0886 Amphibolite Hornblende K/Ar 129 3 Amphibolite, so-called Bermeja Complex in Sierra Bermeja; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 43-1 18.0031 -67.0883 Diorite Hornblende K/Ar 88.2 2.1 Diorite porphyry, so-called Bermeja Complex in Sierra Bermeja; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 53-1b 18.0411 -65.8539 Diorite Hornblende K/Ar 80.2 1.6 Diorite from San Lorenzo batholith; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 53-1a 18.0425 -65.8553 Diorite Hornblende K/Ar 79.7 1.6 Diorite from San Lorenzo batholith; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 51-4 18.0472 -66.0992 Diorite Actinolite K/Ar 102.5 16 Diorite; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 52-1 18.0514 -65.9889 Quartz diorite Hornblende K/Ar 111.4 9 Quartz diorite; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 53-2 18.0983 -65.8394 Quartz monzonite Biotite K/Ar 67.2 1.6 Quartz monzonite from San Lorenzo batholith; date recalculated using constants of Steiger and Jager (1977). Rogers (1977) reports this as Granodiorite of plutonic complex of Punta Guayanes. Cox and others, 1977 Hornblende K/Ar 67.8 2.9 50-4 18.1103 -66.2458 Quartz diorite Hornblende K/Ar 48.3 1.0 Quartz diorite from Cuyon stock; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 Chlorite- biotite K/Ar 49.4 1.3 39-1 18.1258 -65.8633 Granodiorite Biotite K/Ar 67.3 1.6 Granodiorite from San Lorenzo batholith. Biotite age probably lowered by thermal effects of a younger intrusive; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 Hornblende K/Ar 76.0 1.5 38-4 18.1522 -65.9806 Quartz monzonite Biotite K/Ar 74.4 2.0 Quartz monzonite from San Lorenzo batholith; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 Hornblende K/Ar 75.2 1.5 71-203 18.1597 -66.71805 Quartz diorite Hornblende K/Ar 41.1 1.4 Eocene igneous rocks with unaltered hornblende. Hornblende quartz diorite. Barabas, 1982 33-16 18.1667 -66.6061 Quartz diorite Hornblende K/Ar 76.1 1.5 Quartz diorite; date recalculated using constants of Steiger and Jager (1977). Two splits, yielding 74.6 and 77.6 Ma. Cox and others, 1977 MN-217-C-1 18.1667 -66.9542 Amphibolite Hornblende K/Ar 114.8 15 Amphibolite enclosed by serpentinite. Hornblende concentrate contains about 15% hydro-grossular garnet; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 71-197A1 18.1696 -66.69805 Breccia Hornblende K/Ar 45.1 4.1 Eocene igneous rocks with unaltered hornblende. Andesitic volcanic breccia. Barabas, 1982 71-197A2 18.1696 -66.69805 Breccia Hornblende K/Ar 37.0 2.9 Eocene igneous rocks with unaltered hornblende. Andesitic volcanic breccia. Barabas, 1982 71-197A3 18.1696 -66.69805 Breccia Whole rock K/Ar 33.4 3.1 Eocene igneous rocks with unaltered hornblende. Andesitic volcanic breccia. Barabas, 1982 RV-122 18.1875 -66.6797 Quartz diorite Whole rock K/Ar 40.1 0.8 Hydrothermally altered rocks. Cala Abajo ore zone. Drill hole, 114 to 115 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 RV-122 18.1878 -66.6794 Quartz diorite Whole rock K/Ar 39.1 0.8 Hydrothermally altered rocks. Cala Abajo ore zone. Drill hole 139 to 143 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 Whole rock K/Ar 42.6 0.9 Whole rock K/Ar 43.7 0.9 32-5 18.1917 -66.6786 Quartz diorite Hornblende K/Ar 42.3 1.9 Quartz diorite from stream bed at Rio Vivi deposit; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 71-128 18.1919 -66.6783 Quartz diorite Hornblende K/Ar 42.2 1.9 Eocene igneous rocks with unaltered hornblende. Hornblende quartz diorite. Barabas, 1982 33-25 18.1942 -66.5236 Quartz diorite Hornblende K/Ar 68.1 1.3 Quartz diorite; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 22 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Puerto Rico—Continued 71-42 18.195 -66.6792 Basalt Hornblende K/Ar 42.8 5.9 Hydrothermally altered rock. Altered pyroxene basalt. Barabas, 1982 RV-17 18.1956 -66.6847 Quartz diorite Whole rock K/Ar 35.0 0.8 Hydrothermally altered rocks. Piedra Hueca ore zone. Drill hole, 212 to 213 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 RV-17 18.1956 -66.6847 Quartz diorite Whole rock K/Ar 35.9 1.1 Hydrothermally altered rocks. Piedra Hueca ore zone. Drill hole, 314 to 316 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 DDW-1 18.1958 -66.6861 Quartz diorite Biotite K/Ar 42.0 0.9 Hydrothermally altered rocks. Piedra Hueca ore zone. Drill hole, 1.5 to 5 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 DDW-1A 18.1958 -66.6861 Quartz diorite Whole rock K/Ar 41.5 0.8 Hydrothermally altered rocks. Piedra Hueca ore zone. Quartz diorite-tonalite porphyry. Barabas, 1982 DDW-1B 18.1961 -66.6694 Quartz diorite Whole rock K/Ar 41.5 0.8 Hydrothermally altered rocks. Piedra Hueca ore zone. Drill hole, 24.8 to 28.1 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 RV-17 18.1964 -66.6847 Quartz diorite Whole rock K/Ar 33.9 .7 Hydrothermally altered rocks. Piedra Hueca ore zone. Drill hole, 212 to 213 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 DDW-1E 18.1964 -66.685 Volcanic rock Biotite K/Ar 40.6 0.8 Hydrothermally altered rocks. Piedra Hueca ore zone. Drill hole, 88 to 90 m depth. Mafic volcanic inclusion. Barabas, 1982 Whole rock K/Ar 40.4 0.8 DDW-1F 18.1964 -66.6861 Quartz diorite Biotite K/Ar 40.0 0.8 Hydrothermally altered rocks. Piedra Hueca ore zone. Drill hole, 85 to 90 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 DDW-1F 18.1964 -66.6861 Quartz diorite Biotite K/Ar 41.1 0.8 Hydrothermally altered rocks. Piedra Hueca ore zone. Drill hole, 85 to 90 m depth. Quartz diorite- tonalite porphyry. Barabas, 1982 Whole rock K/Ar 43.1 1.1 32-87 18.1967 -66.6786 Quartz diorite Whole rock K/Ar 41.8 0.8 Hydrothermally altered rocks. Sapo Alegre zone. Quartz diorite-tonalite porphyry. Barabas, 1982 Whole rock K/Ar 42.1 0.8 DDE-1Ha 18.1971 -66.685 Tonalite Alunite K/Ar 42.6 2.1 Eocene igneous rocks with unaltered hornblende. Drill hole, 157 to 161 m depth. Barabas, 1982 DDE-1Hb Biotite K/Ar 40.1 1.0 RV-104a 18.1981 -66.685 Tonalite Hornblende K/Ar 44.4 2.6 Eocene igneous rocks with unaltered hornblende. Drill hole, 45 to 48 m depth. Barabas, 1982 RV-104b Biotite K/Ar 40.4 0.8 RV-102a 18.1997 -66.6833 Tonalite Hornblende K/Ar 44.2 1.3 Eocene igneous rocks with unaltered hornblende. Drill hole, 167 to 172 m depth. Barabas, 1982 RV-102b Biotite K/Ar 43.6 0.9 RV-102c Plagioclase K/Ar 40.7 0.8 RV-102 Hornblende K/Ar 42.1 2.5 Eocene igneous rocks with unaltered hornblende. Drill hole 156 to 164 m depth. Barabas, 1982 33-22 18.2033 -66.5528 Tonalite Hornblende K/Ar 67.9 1.8 Latest Cretaceous to Paleocene plutonic rocks. Barabas, 1982 33-17 18.2036 -66.6236 Quartz diorite Hornblende K/Ar 68.8 1.4 Quartz diorite; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 33-24 18.2036 -66.6236 Quartz diorite Hornblende K/Ar 70.6 3.3 Quartz diorite; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 Biotite K/Ar 72.3 1.7 38-5 18.2064 -65.8781 Quartz monzonite Chlorite- biotite K/Ar 63.2 1.5 Quartz monzonite from San Lorenzo batholith. Chlorite-biotite age appears to be too young; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 Hornblende K/Ar 72.2 3.2 71-59a 18.2097 -66.6775 Tonalite Hornblende K/Ar 67.0 2.2 Plutonic rocks with latest Cretaceous hornblende ages and Eocene biotite ages. Tonalite to granodiorite. Barabas, 1982 71-59b Biotite K/Ar 47.8 1.0 32-129 18.2103 -66.6781 Diorite Biotite K/Ar 49.2 1.2 Altered and fractured diorite collected in stream bed at Rio Vivi deposit. Biotite age was lowered by thermal effects of Eocene intrusive; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 Hornblende K/Ar 66.8 1.3 VC-2a 18.2106 -66.6708 Tonalite Biotite K/Ar 46.2 1.5 Eocene igneous rocks with unaltered hornblende. Drill hole, 185 to 190 m depth. Barabas, 1982 VC-2b Biotite K/Ar 43.1 0.9 VC-2c Biotite K/Ar 44.6 1.7 VC-2d Plagioclase K/Ar 41.8 1.3 71-151 18.2114 -66.6994 Andesite(?) Biotite K/Ar 46.8 1.2 Hydrothermally altered rock. Barabas, 1982 DS-34 18.2131 -66.7019 Granodiorite Hornblende K/Ar 41.4 2.0 Eocene igneous rocks with unaltered hornblende. Drill hole, 135 to 150 m depth. Granodiorite porphyry. Barabas, 1982 23 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) Puerto Rico—Continued 71-46a 18.2186 -66.6736 Granodiorite Hornblende K/Ar 61.9 2.3 Plutonic rocks with latest Cretaceous hornblende ages and Eocene biotite ages. Barabas, 1982 Biotite K/Ar 45.7 0.9 71-161 18.2203 -66.7078 Tonalite Hornblende K/Ar 37.7 3.1 Eocene igneous rocks with unaltered hornblende. Tonalite porphyry. Barabas, 1982 71-159 18.2258 -66.711 Tonalite Hornblende K/Ar 57.8 1.5 Latest Cretaceous to Paleocene plutonic rocks. Barabas, 1982 32-12 18.235 -66.7219 Quartz diorite Hornblende K/Ar 38.8 1.5 Quartz diorite from stream bed of Rio Grande de Arecibo; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 31-1 18.2397 -66.8572 Porphyry Hornblende K/Ar 42.8 5.6 Hornblende porphyry from Torrecilla stock; date recalculated using constants of Steiger and Jager (1977). Separate 60–100 mesh. Cox and others, 1977; Barabas, 1982 45.3 4.0 Separate 100–150 mesh. 71-49 18.2447 -66.7947 Andesite Hornblende K/Ar 40.6 0.9 Eocene igneous rocks with unaltered hornblende. Helecho ore zone. Location in error in source, minutes transposed in latitude? Barabas, 1982 71-166 18.245 -66.7225 Granite Hornblende K/Ar 66.3 1.4 Latest Cretaceous to Paleocene plutonic rocks. Barabas, 1982 71-58a 18.2456 -66.7986 Tonalite Hornblende K/Ar 34.7 3.3 Eocene igneous rocks with unaltered hornblende. Helecho ore zone. Tonalite porphyry. Barabas, 1982 71-58b Hornblende K/Ar 43.2 4.5 17-140 18.2556 -66.7925 Gangue Whole rock K/Ar 44.5 1.3 Quartz-sericite whole rock date. Gangue from hydrothermally altered porphyry at Tanama in core from 811-ft interval, drill hole no. T116 (inclined at 45°); date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 17-141 18.2556 -66.7925 Gangue Whole rock K/Ar 42.4 1.9 Quartz-sericite whole rock date. Gangue from hydrothermally altered porphyry at Tanama in a core from 419-ft interval, drill hole no. T116 (inclined at 45°); date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 71-75 18.2788 -66.6544 Granodiorite Hornblende K/Ar 66.1 4.1 Latest Cretaceous to Paleocene plutonic rocks. Barabas, 1982 71-76 18.2792 -66.655 Granodiorite Alunite K/Ar 61.1 3.2 Latest Cretaceous to Paleocene plutonic rocks. Barabas, 1982 18-5 18.2797 -66.6569 Quartz monzonite Hornblende K/Ar 70.0 2.1 Quartz monzonite from Utuado batholith; collected below dam face at Lago Caonillas; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 71-74 18.2833 -66.6442 Granodiorite Hornblende K/Ar 60.5 2.6 Latest Cretaceous to Paleocene plutonic rocks. Hornblende granodiorite porphyry. Barabas, 1982 71-154 18.2853 -66.7969 Tonalite Hornblende K/Ar 63.3 1.9 Latest Cretaceous to Paleocene plutonic rocks. Barabas, 1982 22-1 18.2897 -66.1408 Altered rock Whole rock K/Ar 76.8 1.8 Quartz sericite whole rock date. Hydrothermally altered Santa Olaya Lava; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 25-1 18.2931 -65.7944 Diorite Hornblende K/Ar 46.8 2.2 Quartz diorite from Rio Blanco stock; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 Biotite K/Ar 47.3 1.1 71-153 18.2983 -66.8233 Tonalite Hornblende K/Ar 68.7 2 Latest Cretaceous to Paleocene plutonic rocks. Barabas, 1982 20-1 18.3022 -66.4108 Quartz monzonite Hornblende K/Ar 90.2 1.8 Quartz monzonite from Morovis stock; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 15-1 18.3369 -67.0469 Andesite Plagioclase K/Ar 41.7 0.8 Andesite porphyry which is found as residual boulders in Rio Culebrines Formation; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 Hornblende K/Ar 44.2 0.9 23-8 18.3417 -66.0956 Andesite Hornblende K/Ar 61.8 1.2 Guaracanal andesite; date recalculated using constants of Steiger and Jager (1977). Cox and others, 1977 VB-1 18.3614 -66.6836 Tonalite Biotite K/Ar 40.1 1.5 Hydrothermally altered rocks. Drill hole 74.5 to 76 m depth. Barabas, 1982 U.S. Virgin Islands Robin Bay 17.7313 -64.6238 Mafic volcanic rock Hornblende K/Ar 75.2 4.3 Pale-brown hornblende, 86% and moderately chloritized hornblende, 14%. Average of 2 determinations. Clast in East End Member of Caledonia Formation Speed and others, 1979 Grapetree Point 17.7455 -64.5993 Mafic dike Hornblende K/Ar 70.1 3.9 Pale-brown hornblende, 99%, and clinopyroxene, 1%. Average of 2 determinations. Speed and others, 1979 East Point 17.7544 -64.5670 Mafic dike Hornblende K/Ar 71.8 2.2 Green-brown hornblende. Speed and others, 1979 Pull Point 17.7652 -64.6554 Gabbro Hornblende K/Ar 66.0 3.2 Deep-brown hornblende, 98%; mica-epidote-prehnite intergrowths, 2%. Average of 2 determinations. Speed and others, 1979 Green Cay 17.7671 -64.6657 Mafic dike Hornblende K/Ar 66.1 1.8 Green-brown hornblende. Speed and others, 1979 SJ765R1 18.3232 -64.7310 Rhyolite Whole rock K/Ar 30.9 0.3 Water Island Formation. Alminas and others, 1994 SJ048R 18.3275 -64.7658 Rhyolite Whole rock K/Ar 50.2 5.7 Water Island Formation. Alminas and others, 1994 24 Sample no. Latitude (decimal degrees) Longitude (decimal degrees) Rock type Mineral Method Age (Ma) Analytical error (Ma) Comments Reference(s) U.S. Virgin Islands—Continued ST120R 18.3278 -64.9311 Rhyolite Whole rock K/Ar 65.8 2.9 Water Island Formation. Sample collection coordinates revised to place sample onshore. Alminas and others, 1994 VI 15 18.3306 -64.95805 Granitic rock Whole rock K/Ar 40.94 2.05 Haypiece Hill, fine-grained granitic(?) rock of the Virgin Island batholith on Saint Thomas. Vila and others, 1986 n/a 18.3328 -64.9692 Keratophyre Whole rock K/Ar 59.5 5 K/Ar date on celadonitic keratophyre tuff. Location only described as Water Island Formation and age was considered too young, representing argon leakage of later formation of celadonite. Location here is probably incorrect as no location was provided in source. Date recalculated using constants of Steiger and Jager (1977) assuming old constants were in use. Donnelly, 1966 Whole rock K/Ar 63.6 5 n/a 18.3328 -64.9692 Keratophyre Whole rock K/Ar 106 10 K/Ar date on keratophyre. Location described as west shore of Lindbergh Bay in Water Island Formation. Location approximate. Donnelly, 1966 Whole rock K/Ar 110 10 VI 20 18.3331 -64.9711 Basalt Whole rock K/Ar 37.44 1.87 Basalt dike in quarry at Cabritaberg on Saint Thomas. Vila and others, 1986 ST115R 18.3356 -64.9442 Rhyolite Whole rock K/Ar 40.7 1.1 Water Island Formation. Alminas and others, 1994 VI 38 18.33721 667 -64.9587 Basalt Whole rock K/Ar 50.03 2.70 Near Sara Hill, mafic dike containing large amphibole? Vila and others, 1986 STT 784 18.3372 -64.9608 Basalt Whole rock K/Ar 58.83 2.94 Sara Hill, mafic dike containing large amphibole? Vila and others, 1986 SJ685R 18.3417 -64.7242 Rhyolite Whole rock K/Ar 37.7 1.1 Louisenhoj Formation. Thought to provide a minimum age of mineralization. Alminas and others, 1994 SJ747R1 18.3486 -64.7736 Andesite Whole rock K/Ar 42.1 0.6 Louisenhoj Formation Alminas and others, 1994 SJ748R 18.3586 -64.7014 Andesite Whole rock K/Ar 38.6 0.8 Water Island Formation Alminas and others, 1994 VI-85-193 18.3621 -64.6942 Tonalite Hornblende 40/39 Plateau 38.81 0.14 Narrows pluton, Please horizontal control marker, eastern Saint John quadrangle. Approximate location, read from map. Rankin, 2002 VI 39 18.3687 -64.9722 Diorite Whole rock K/Ar 59.03 2.95 Small diorite intrusion on northwestern Saint Thomas. Vila and others, 1986 VI 8 18.3687 -64.9722 Basalt Whole rock K/Ar 82.06 4.10 Basaltic dike containing amphibole at Coki Point on Saint Thomas is distinguished by its much older age than mafic dikes taken on the southern coast of Saint Thomas. Vila and others, 1986 VI-85-222 18.3691 -64.7334 Tonalite Hornblende 40/39 Plateau 38.67 0.22 Narrows pluton, northeast corner, Mary Point, western Saint John quadrangle. Approximate location, read from map. Rankin, 2002 VI-85-218 18.3726 -64.7505 Quartz gabbro Hornblende 40/39 Plateau 39.29 0.22 Narrows pluton, northwestern shore, Mary Point, western Saint John quadrangle. Approximate location, read from map. Rankin, 2002