Geologic Map of the Eaton Reservoir Quadrangle, Larimer County, Colorado and Albany County, Wyoming

Scientific Investigations Map 3029



New geologic mapping of the Eaton Reservoir 7.5' quadrangle defines geologic relationships in the northern Front Range along the Colorado/Wyoming border approximately 35 km south of Laramie, Wyo. Previous mapping within the quadrangle was limited to regional reconnaissance mapping (Tweto, 1979; Camp, 1979; Burch, 1983) and some minor site-specific studies (Carlson and Marsh, 1986; W. Braddock, unpub. mapping, 1982). Braddock and others (1989) mapped the Diamond Peak 7.5' quadrangle to the east, Burch (1983) mapped rocks of the Rawah batholith to the south, W. Braddock (unpub. mapping, 1981) mapped the Sand Creek Pass 7.5' quadrangle to the west, and Ver Ploeg and Boyd (2000) mapped the Laramie 30' x 60' quadrangle to the north. Field work was completed during 2005 and 2006 and the mapping was compiled at a scale of 1:24,000. Minimal petrographic work and isotope dating was done in connection with the present mapping, but detailed petrographic and isotope studies were carried out on correlative map units in surrounding areas as part of a related regional study of the northern Front Range. Classification of Proterozoic rocks is primarily based upon field observation of bulk mineral composition, macroscopic textural features, and field relationships that allow for correlation with rocks studied in greater detail outside of the map area.

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Geologic Map of the Eaton Reservoir Quadrangle, Larimer County, Colorado and Albany County, Wyoming
Series title Scientific Investigations Map
Series number 3029
DOI 10.3133/sim3029
Edition Version 1.0
Year Published 2008
Language ENGLISH
Publisher Geological Survey (U.S.)
Contributing office(s) U.S. Geological Survey
Description Map Sheet: 43 x 29 inches; Downloads Directory
Projection Polyconic
Scale 24000
Additional Online Files (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details