New chemical, isotopic, and fluid inclusion data from zinc-lead-copper veins, Shawangunk Mountains, New York

Possible Mesozoic age of Ellenville Zn-Pb-Cu(Ag) deposit, Shawangunk Mountains, New York

“…Open-space vein filling with highly developed euhedral quartz, chalcopyrite, galena, and brookite; vertical zoning of sulfide minerals over short distances; and fluid-inclusion Cox (1970), Smith (1977), Robinson and Woodruff (1988), Sloto (1989), Wilbur et al (1990), and from observations by J.D. Friedman and F.E.…”

“…Generalized paragenetic relations for Shawangunk Mountains vein deposits. Abbreviations: G early granulated quartz, MS main-stage quartz deposited throughout base-metal sulfide stages as indicated by inclusions of galena, sphalerite, chalcopyrite, eovellite, chalcocite, and an unidentified cobaltite-group mineral in euhedral quartz crystals (Wilbur et al 1990). …”

“…Fluid-inclusion studies (Wilbur et al 1990) indicate mineral deposition at ~ 150 ~ to 230 ~ from moderately saline (5 to 15 wt percent NaC1 equivalent) brines. Temperature and salinity fluctuations observed in zoned quartz crystals reflect repeated mixing of two or more fluids of different temperatures and salinities during mineralization.…”

“…Temperature and salinity fluctuations observed in zoned quartz crystals reflect repeated mixing of two or more fluids of different temperatures and salinities during mineralization. These fluctuations may represent episodic seismic pumping of deep-source, hot, saline, perhaps connate, brines into a dominantly meteoric water hydrothermal system (Wilbur et al 1990). Other mixing scenarios are also possible.…”

“…Friedman and F.E. Mutschler Fluid data from fluid-inclusion studies (Robinson and Woodruff, 1988;Wilbur et al 1990) XX, Common; X, accessory (or reported); R, rare; high Hg, > 50 ppm, high Ag, > 100 ppm homogenization temperatures of ~ 150-230~ (Wilbur et al 1990) all suggest postorogenic epithermal conditions. The above features are typical of Zn-Pb-Cu sulfide veins with high Ag content which are associated with continental rift basins ranging in age from Proterozoic to Cenozoic (Parnell 1986;Ro-bbins 1983;Robinson and Woodruff 1988).…”