The Las Vegas Formation

Professional Paper 1839
By: , and 

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Abstract

The Las Vegas Formation was established in 1965 to designate the distinctive light-colored, fine-grained, fossil-bearing sedimentary deposits exposed in and around the Las Vegas Valley, Nevada. In a coeval designation, the sediments were subdivided into informal units with stratigraphic and chronologic frameworks that have persisted in the literature. Use of the Las Vegas Formation name over the past half century has been hampered because of the lack of a robust definition and characterization of the entire lithostratigraphic sequence, its geographic distribution, and chronology. This study evaluates and describes deposits attributed to the Las Vegas Formation with detailed stratigraphy, sedimentology, and field relations. A large suite of radiocarbon and luminescence ages facilitates revision and temporal expansion of the geochronology. In all, we characterize 17 informal geologic units within the formation, each dating to a unique period of geologic time, with stratigraphically ascending members X, A, B, D, and E and attendant beds in members B, D, and E. The age of the Las Vegas Formation spans at least the middle Pleistocene to early Holocene (from approximately 573 to 8.53 kilo-annum [thousands of years before present]) and is related to past episodes of groundwater discharge in the Las Vegas Valley. The contextual information derived from this new framework is dually noteworthy because the sediments entomb one of the most significant Pleistocene vertebrate faunas in the American Southwest, the Tule Springs local fauna, and represent a paleohydrologic system that responded dynamically to abrupt changes in climate throughout the late Quaternary. Characterizing the nature of these important deposits stabilizes the nomenclature, promotes the continued use of the informal units within the formation, and facilitates studies of similar deposits associated with desert wetland ecosystems elsewhere in the southwestern United States.

Suggested Citation

Springer, K.B., Pigati, J.S., Manker, C.R., and Mahan, S.A., 2018, The Las Vegas Formation: U.S. Geological Survey Professional Paper 1839, 62 p., https://doi.org/10.3133/pp1839.

ISSN: 2330-7102 (online)

ISSN: 1044-9612 (print)

Study Area

Table of Contents

  • Acknowledgments
  • Abstract
  • Introduction
  • Methods
  • Results and Discussion
  • Conclusions
  • References
  • Appendix 1. Summary of Radiocarbon Ages Obtained Previously for the Las Vegas Formation
  • Appendix 2. Summary of Thermoluminescence Ages Obtained Previously for the Las Vegas Formation
  • Appendix 3. Summary of Sample Information and Optically Stimulated Luminescence Ages From This Study

Additional publication details

Publication type Report
Publication Subtype USGS Numbered Series
Title The Las Vegas Formation
Series title Professional Paper
Series number 1839
ISBN 978-1-4113-4237-8
DOI 10.3133/pp1839
Year Published 2018
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Geosciences and Environmental Change Science Center
Description vii, 62 p.
Country United States
State Nevada
Other Geospatial Las Vegas Formation
Online Only (Y/N) N