Reference 3351
Gilluly, James; Masursky, Harold (1965) U. S. Geological Survey Bulletin, Report: B 1175, 117 pp., 1965
| Authors | Gilluly, James; Masursky, Harold |
|---|---|
| Year | 1965 |
| Source | U. S. Geological Survey Bulletin, Report: B 1175, 117 pp., 1965 |
| Pages | 117 pp. |
| Publisher | U. S. Geological Survey, Reston, VA, United States USA |
| ISSN | 8755-531X |
| GeoRef | 1965-018945 |
| Keywords | aeromagnetic; areal geology; Bouguer gravity; Cenozoic; Cortez quadrangle; economic geology; faults; geologic; maps; Mesozoic; metal ores; Nevada; overthrust; Paleozoic; polymetallic ores; Roberts thrust; stratigraphy; United States; USGS |
Abstract
The stratigraphy, structure, and economic geology of the Cortez quadrangle, in north-central Nevada, are discussed. The area is of particular interest because of the formerly active bonanza silver cap at Cortez and because of the exposure of the Roberts thrust, one of the great structures of the Cordillera and critical to an understanding of Cordilleran evolution. Paleozoic, Mesozoic, and Cenozoic strata and Tertiary volcanics are exposed in the area. The Roberts thrust is latest Devonian or Early Mississippian in age. Basin and Range faults originated in Pliocene and have been active in post-Pleistocene. Major polymetallic sulfide ores at Cortez are chiefly manto deposits in the Hamburg Dolomite, although large tonnages have been obtained from fissure veins associated with quartz porphyry dikes.
15 samples from this reference
| Sample | Rock name | Major | Trace | Isotope |
|---|---|---|---|---|
| 1 | Tuff | yes | yes | |
| 2 | Tuff | yes | yes | |
| 3 | Tuff | yes | yes | |
| 4 | Vitrophere | yes | yes | |
| 5 | Tuff | yes | yes | |
| 6 | Pyroclastic-fall | yes | yes | |
| 7 | Vitrophere | yes | yes | |
| 8 | Tuff | yes | yes | |
| 1 | Not given | yes | yes | |
| 2 | Not given | yes | yes | |
| 1 | Rhyolite | yes | yes | |
| 2 | Rhyolite | yes | yes | |
| 1 | Basaltic-andesite | yes | yes | |
| 2 | Basaltic-andesite | yes | ||
| No Number | Rhyolite | yes | yes |