Characterization Of The Dat Zone, Eastern Alaska Range, Alaska: A Calcic Iron (Copper-Gold) Skarn Prospect
dc.contributor.author | Athey, Jennifer Erin | |
dc.date.accessioned | 2018-06-06T23:30:47Z | |
dc.date.available | 2018-06-06T23:30:47Z | |
dc.date.issued | 1999 | |
dc.identifier.uri | http://hdl.handle.net/11122/8538 | |
dc.description | Thesis (M.S.) University of Alaska Fairbanks, 1999 | |
dc.description.abstract | I studied a Cu-Fe-Au prospect in the eastern Alaska Range, Alaska, informally known as 'the DAT Zone'. Previous workers disagreed about the prospect's genesis; my work conclusively shows it to be a calcic iron skarn deposit with late quartz-pyrite-gold mineralization, broadly coeval with the host Pennsylvanian island arc-related volcanic and associated sedimentary rocks. A sericite-quartz-pyrite altered shear yields a $\sp{40}$Ar/$\sp{39}$Ar age similar to that of a nearby quartz monzodiorite pluton (300 Ma $\pm$ 1 Ma). The skarn consists of andradite extensively retrograded to ferrotremolite, quartz, magnetite, hematite, calcite, and chalcopyrite. Based on alteration pseudomorphs, the prograde assemblage was clinopyroxene with 20-40 %Hd, wollastonite, and andradite. The main-stage fluids were approximately 600$\sp\circ$C, moderately oxidized, and extremely saline ($>$60% NaCl equivalent). This fluid was clearly different from those of volcanogenic massive sulfide, metamorphic, or epithermal deposits. The lack of explosive textures is inconsistent with the DAT Zone as a porphyry copper deposit. <p> | |
dc.subject | Geology | |
dc.title | Characterization Of The Dat Zone, Eastern Alaska Range, Alaska: A Calcic Iron (Copper-Gold) Skarn Prospect | |
dc.type | Thesis | |
dc.type.degree | ms | |
dc.identifier.department | Department of Geology and Geophysics | |
dc.contributor.chair | Newberry, Rainer | |
refterms.dateFOA | 2020-03-05T15:58:34Z |
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