Aeolian sediments in paleowetland deposits of the Las Vegas Formation

Quaternary Research
By: , and 

Links

Abstract

The Las Vegas Formation (LVF) is a well-characterized sequence of groundwater discharge (GWD) deposits exposed in and around the Las Vegas Valley in southern Nevada. Nearly monolithologic bedrock surrounds the valley, which provides an excellent opportunity to test the hypothesis that GWD deposits include an aeolian component. Mineralogical data indicate that the LVF sediments are dominated by carbonate minerals, similar to the local bedrock, but silicate minerals are also present. The median particle size is ~35 μm, consistent with modern dust in the region, and magnetic properties contrast strongly with local bedrock, implying an extralocal origin. By combining geochemical data from the LVF sediments and modern dust, we found that an average of ~25% of the LVF deposits were introduced by aeolian processes. The remainder consists primarily of authigenic groundwater carbonate as well as minor amounts of alluvial material and soil carbonate. Our data also show that the aeolian sediments accumulated in spring ecosystems in the Las Vegas Valley in a manner that was independent of both time and the specific hydrologic environment. These results have broad implications for investigations of GWD deposits located elsewhere in the southwestern U.S. and worldwide.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Aeolian sediments in paleowetland deposits of the Las Vegas Formation
Series title Quaternary Research
DOI 10.1017/qua.2021.14
Edition Online First
Year Published 2021
Language English
Publisher Cambridge University Press
Contributing office(s) Geosciences and Environmental Change Science Center
Country United States
State Nevada
Other Geospatial Las Vegas Valley watershed
Google Analytic Metrics Metrics page
Additional publication details