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| | USGS Open-File Report 98-340, Zinc-Lead mineralization, Nasina Assemblage (Site not responding. Last check: 2007-10-29) |
 | | The Yukon-Tanana Upland of east-central Alaska and Yukon comprises thrust sheets of ductilely deformed metasedimentary and metaigneous rocks of uncertain age and origin that are overlain by klippen of weakly metamorphosed oceanic rocks of the Seventymile-Slide Mountain terrane, and intruded by post-kinematic Early Jurassic, Cretaceous and Tertiary granitoids. |
 | | Metamorphosed continental margin strata in the Yukon-Tanana Upland of east-central Alaska are thought to be correlative, on the basis of stratigraphic similarities and sparse Mississippian U-Pb zircon and fossil ages (Mortensen, 1992), with middle Paleozoic metasedimentary and metavolcanic rocks in the eastern Alaska Range and in western and southeastern Yukon. |
 | | The prospect is underlain by a regionally and contact-metamorphosed, relatively undeformed section of carbonaceous schist, quartz-mica schist, pyritic metachert, felsic metatuff, and marble. |
| geopubs.wr.usgs.gov /open-file/of98-340 (2884 words) |
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