Paleogene sedimentary basin development in southern Nevada, USA
Links
- More information: Publisher Index Page (via DOI)
- Data Release: USGS data release - U-Pb detrital zircon data and Ar feldspar data from middle Cenozoic sandstones and volcanic tuffs from southern Nevada, USA
- Open Access Version: Publisher Index Page
- Download citation as: RIS | Dublin Core
Abstract
The cause of the transition from Mesozoic and early Cenozoic crustal shortening to later extension in the western United States is debated. In many parts of the extant Sevier hinterland, now the Basin and Range Province, the sedimentary sections that provide the most direct record of that transition remain poorly studied and lack meaningful age control. In this paper, we present field characterization supported by U-Pb detrital zircon and 40Ar/39Ar feldspar ages for ten sections across southern Nevada. We describe a newly identified basin, here named the Fallout Hills basin, which preserves >1.0 km of sedimentary deposits as old as middle Eocene, ca. 48 Ma. Deposition occurred during the 20 m.y. (million years) before the 27.60 ± 0.03 Ma Monotony Tuff blanketed much of south-central Nevada, based on 47.6 Ma and younger detrital zircon maximum depositional ages (MDAs) from near the Pintwater and Spotted Ranges. Elsewhere in southern Nevada, prevolcanic Cenozoic strata commonly form thinner (~100 m), isolated exposures that yield detrital zircon MDAs ≤10 m.y. older than (and in some cases essentially the same age as) the ca. 27–28 Ma ignimbrites that cap the sections. A variable but overall upward-fining facies pattern is observed in both the Fallout Hills basin and the thinner sections. These localized patterns imply topographic changes that are unlikely to reflect plate-scale processes and are not consistent with large-magnitude extension. Instead, variable uplift due to magmatism combined with antecedent topographic relief from thrust faulting and subsequent erosion likely provided accommodation for these deposits.
Study Area
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | Paleogene sedimentary basin development in southern Nevada, USA |
| Series title | Lithosphere |
| DOI | 10.2113/2024/lithosphere_2023_225 |
| Volume | 2024 |
| Issue | 1 |
| Year Published | 2024 |
| Language | English |
| Publisher | GeoScienceWorld |
| Contributing office(s) | Geosciences and Environmental Change Science Center, Geology, Geophysics, and Geochemistry Science Center |
| Description | 34 p. |
| First page | 1 |
| Last page | 34 |
| Country | United States |
| State | Nevada |
| Google Analytic Metrics | Metrics page |