Description
Location: Elko, Nevada
Contact: justin.b.milliard@gmail.com
Presenter: Emily White, Texas A&M University
Title: Petrogenetic Evolution and Exhumation Histories of Jurassic–Eocene plutons in the Northern Great Basin: Impacts on Carlin- and Porphyry-Type Deposit Models
Western Folklife Center, 501 Railroad St., Elko, NV
Food and Drinks @ 6 p.m., Talk to begin @ 7 p.m.
FOOD & BEER SPONSOR: MAJOR DRILLING
Abstract:
Petrogenic and thermochronologic study of Jurassic–Eocene retroarc plutons in the North American Cordilleran hinterland of eastern Nevada and western Utah provide key constraints on the timing and style of magmatism and upper-crustal deformation in the Sevier–Laramide orogen. Results from isolated sites across the hinterland support the general existence of high-magnitude Cretaceous and Paleogene exhumation in the hinterland, but quantitative constraints on Cretaceous–Eocene cooling histories are spatially limited. We present preliminary results from trace and rare earth element geochemistry, zircon and apatite U-Pb geochronology, and (U-Th)/He thermochronology of Jurassic–Eocene plutonic samples collected across a broad E–W transect of the Nevada–Utah hinterland. A combination of high- and low-temperature geothermometric and thermochronologic constraints provide quantitative estimates of mid- to upper-crustal unroofing in the hinterland. Preliminary geochemical results of Jurassic–Cretaceous plutons reveal: (1) broadly similar whole rock and trace element geochemistry suggesting correlative petrogenic emplacement histories, (2) trace element variations are related to proximal porphyry- and skarn-type alteration, and (3) the degree of alumina saturation is indicative of peraluminous plutons formed through partial melting of metasedimentary rocks. New apatite U-Pb geochronology and (U-Th)/He thermochronology indicates three prominent phases of exhumation during the Late Cretaceous, Paleogene, and Miocene. The preponderance of apatite grains with Cretaceous–Paleogene (U-Th)/He cooling ages are consistent with recent hypotheses of significant early, pre-Basin-and-Range, exhumation in the North American Cordilleran hinterland.
If you have any questions, please contact Elko Chapter President Justin Milliard at: justin.b.milliard@gmail.com
Details
02/16/2023 19:00:0002/16/2023 20:30:00America/Los_AngelesGSN Elko Chapter Meeting – Thursday, Feb. 16, 2023 @ 7:00 p.m.Presenter: Emily White, Texas A&M University Title: Petrogenetic Evolution and Exhumation Histories of Jurassic–Eocene plutons in the Northern Great Basin: Impacts on Carlin- and Porphyry-Type Deposit Models Western Folklife Center, 501 Railroad St., Elko, NV Food and Drinks @ 6 p.m., Talk to begin @ 7 p.m. FOOD & BEER SPONSOR: MAJOR DRILLING Abstract: Petrogenic and thermochronologic study of Jurassic–Eocene retroarc plutons in the North American Cordilleran hinterland of eastern Nevada and western Utah provide key constraints on the timing and style of magmatism and upper-crustal deformation in the Sevier–Laramide orogen. Results from isolated sites across the hinterland support the general existence of high-magnitude Cretaceous and Paleogene exhumation in the hinterland, but quantitative constraints on Cretaceous–Eocene cooling histories are spatially limited. We present preliminary results from trace and rare earth element geochemistry, zircon and apatite U-Pb geochronology, and (U-Th)/He thermochronology of Jurassic–Eocene plutonic samples collected across a broad E–W transect of the Nevada–Utah hinterland. A combination of high- and low-temperature geothermometric and thermochronologic constraints provide quantitative estimates of mid- to upper-crustal unroofing in the hinterland. Preliminary geochemical results of Jurassic–Cretaceous plutons reveal: (1) broadly similar whole rock and trace element geochemistry suggesting correlative petrogenic emplacement histories, (2) trace element variations are related to proximal porphyry- and skarn-type alteration, and (3) the degree of alumina saturation is indicative of peraluminous plutons formed through partial melting of metasedimentary rocks. New apatite U-Pb geochronology and (U-Th)/He thermochronology indicates three prominent phases of exhumation during the Late Cretaceous, Paleogene, and Miocene. The preponderance of apatite grains with Cretaceous–Paleogene (U-Th)/He cooling ages are consistent with recent hypotheses of significant early, pre-Basin-and-Range, exhumation in the North American Cordilleran hinterland. If you have any questions, please contact Elko Chapter President Justin Milliard at: justin.b.milliard@gmail.comReno, NV| Event Starts | Event Ends |
| 02/16/2023 | 02/16/2023 |
| All Day Event | |
| 7:00pm | 8:30pm |