Geologic map of the Lower Valley quadrangle, Caribou County, Idaho

Scientific Investigations Map 3215
By: , and 



The Lower Valley 7.5-minute quadrangle, located in the core of the Southeast Idaho Phosphate Resource Area, includes Mississippian to Triassic marine sedimentary rocks, Pliocene to Pleistocene basalt, and Tertiary to Holocene surficial deposits. The Mississippian to Triassic marine sedimentary sequence was deposited on a shallow shelf between an emergent craton to the east and the Antler orogenic belt to the west. The Meade Peak Phosphatic Shale Member of the Permian Phosphoria Formation hosts high-grade deposits of phosphate that were the subject of geologic studies through much of the 20th century. Open-pit mining of the phosphate has been underway within and near the Lower Valley quadrangle for several decades.

Suggested Citation

Oberlindacher, H.P., Hovland, R.D., Miller, S.T. , Evans, J.G., and Miller, R.J., 2018, Geologic map of the Lower Valley quadrangle, Caribou County, Idaho: U.S. Geological Survey Scientific Investigations Map 3215, 6 p., 1 sheet, scale 1:24,000,

ISSN: 2329-132X (online)

Study Area

Table of Contents

  • Acknowledgments
  • Abstract
  • Introduction
  • Synopsis of Geology
  • References Cited
Publication type Report
Publication Subtype USGS Numbered Series
Title Geologic map of the Lower Valley quadrangle, Caribou County, Idaho
Series title Scientific Investigations Map
Series number 3215
DOI 10.3133/sim3215
Year Published 2018
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Geology, Minerals, Energy, and Geophysics Science Center
Description Map: 35.72 x 31.32 inches; Pamphlet: iii, 6 p.; Spatial Data; Metadata; Read Me
Country United States
State Idaho
County Caribou County
Other Geospatial Lower Valley quadrangle
Online Only (Y/N) Y
Additional Online Files (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details