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Structural controls on Carlin-type gold mineralization in the gold bar district, Eureka County, Nevada

O. Yigit·E.P. Nelson·M.W. Hitzman·A. H. Hofstra
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Abstract

The Gold Bar district in the southern Roberts Mountains, 48 km northwest of Eureka , Nevada , contains one main deposit ( Gold Bar ), five satellite deposits, and other resources. Approximately 0.5 Moz of gold have been recovered from a resource of 1,639,000 oz of gold in Carlin - type gold deposits in 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 gold mineralization indicate that both pre-Tertiary and Tertiary structures were important controls on gold mineralization . Gold mineralization 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 in some strata-bound zones, accounts for a small portion of the ore in every deposit. In the Gold 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.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 39.232253141714885° to 39.787433886224406° latitude; -116.3177490234375° to -115.697021484375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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O. Yigit, E.P. Nelson, M.W. Hitzman, A. H. Hofstra. 2003. Structural controls on Carlin-type gold mineralization in the gold bar district, Eureka County, Nevada. https://doi.org/10.2113/gsecongeo.98.6.1173

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