Burial and exhumation history of Mississippian strata in east-central Nevada

Zircon (U-Th)/He analyses and vitrinite reflectance (Ro) analyses were performed on a suite of Mississippian sedimentary rocks collected in east-central Nevada in order to test Permian exhumation described in a previous study.;The zircon analyses produced three clusters of ages: 1) older than, 2) similar to, and 3) younger than depositional age. The majority of zircons shows ages that are older than the sandstone deposition age. Young ages were recorded in three localities that may indicate reset ages/residence within the (U-Th)/He partial retention zone (HePRZ). Moderate-high ratios of Th/U may indicate a magmatic source. Vitrinite reflectance (Ro) analyses show values between 0.54% - 1.56% which indicate early mature - postmature stage with respect to potential hydrocarbon maturation. The hypothesized regional Permian exhumation was not documented in this study, and the Ro values in all locations are too low to have caused thermal resetting of the (U-Th)/He system.