E.P. Nelson
M.W. Hitzman
A. H. Hofstra
O. Yigit
2003
<p><span>The </span>Gold<span> </span>Bar<span> </span>district<span> </span>in<span> the southern Roberts Mountains, 48 km northwest of </span>Eureka<span>, </span>Nevada<span>, contains one main deposit (</span>Gold<span> </span>Bar<span>), five satellite deposits, and other resources. Approximately 0.5 Moz of </span>gold<span> have been recovered from a resource of 1,639,000 oz of </span>gold<span> </span>in<span> </span>Carlin<span>-</span>type<span> </span>gold<span> deposits </span>in<span> lower plate, miogeoclinal carbonate rocks below the Roberts Mountains thrust. Host rocks are unit 2 of the Upper Member of the Devonian Denay Formation and the Bartine Member of the McColley Canyon Formation. Spatial and temporal relations between structures and </span>gold<span> </span>mineralization<span> indicate that both pre-Tertiary and Tertiary structures were important </span>controls<span> on </span>gold<span> </span>mineralization<span>. </span>Gold<span> </span>mineralization<span> occurs primarily along high-angle Tertiary normal faults, some of which are reactivated reverse faults of Paleozoic or Mesozoic age. Most deposits are localized at the intersection of northwest- and northeast-striking faults. Alteration includes decalcification, and to a lesser extent, silicification along high-angle faults. Jasperoid (pervasive silicification), which formed along most faults and </span>in<span> some strata-bound zones, accounts for a small portion of the ore </span>in<span> every deposit. </span>In<span> the </span>Gold<span> Canyon deposit, a high-grade jasperoid pipe formed along a Tertiary normal fault which was localized along a zone of overturned fault-propagation folds and thrust faults of Paleozoic or Mesozoic age.</span></p>
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10.2113/gsecongeo.98.6.1173
en
Society of Economic Geologists
Structural controls on Carlin-type gold mineralization in the gold bar district, Eureka County, Nevada
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