Preliminary geologic map of the Big Costilla Peak area, Taos County, New Mexico, and Costilla County, Colorado

Open-File Report 2012-1041
By: , and 



This map covers the Big Costilla Peak, New Mex.&nash;Colo. quadrangle and adjacent parts of three other 7.5 minute quadrangles: Amalia, New Mex.–Colo., Latir Peak, New Mex., and Comanche Point, New Mex. The study area is in the southwesternmost part of that segment of the Sangre de Cristo Mountains known as the Culebra Range; the Taos Range segment lies to the southwest of Costilla Creek and its tributary, Comanche Creek. The map area extends over all but the northernmost part of the Big Costilla horst, a late Cenozoic uplift of Proterozoic (1.7-Ga and less than 1.4-Ga) rocks that is largely surrounded by down-faulted middle to late Cenozoic (about 40 Ma to about 1 Ma) rocks exposed at significantly lower elevations. This horst is bounded on the northwest side by the San Pedro horst and Culebra graben, on the northeast and east sides by the Devils Park graben, and on the southwest side by the (about 30 Ma to about 25 Ma) Latir volcanic field. The area of this volcanic field, at the north end of the Taos Range, has undergone significantly greater extension than the area to the north of Costilla Creek. The horsts and grabens discussed above are all peripheral structures on the eastern flank of the San Luis basin, which is the axial part of the (about 26 Ma to present) Rio Grande rift at the latitude of the map. The Raton Basin lies to the east of the Culebra segment of the Sangre de Cristo Mountains. This foreland basin formed during, and is related to, the original uplift of the Sangre de Cristo Mountains which was driven by tectonic contraction of the Laramide (about 70 Ma to about 40 Ma) orogeny. Renewed uplift and structural modification of these mountains has occurred during formation of the Rio Grande rift. Surficial deposits in the study area include alluvial, mass-movement, and glacial deposits of middle Pleistocene to Holocene age.

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Preliminary geologic map of the Big Costilla Peak area, Taos County, New Mexico, and Costilla County, Colorado
Series title Open-File Report
Series number 2012-1041
DOI 10.3133/ofr20121041
Year Published 2012
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Geology and Environmental Change Science Center
Description Map: 50.99 x 44.99 inches; Geospacial Database download
Country United States
State New Mexico
City Amalia
Other Geospatial Big Costilla Peak
Datum North American Datum of 1927
Projection Polyconic
Scale 24000
Google Analytic Metrics Metrics page
Additional publication details