Unknown Quartz - Feldspar Occurrence (MRDS - 10238892), Jamestown District, Boulder Co., Colorado, USA
|Latitude & Longitude (WGS84):||40° 8' 25'' North , 105° 21' 57'' West|
|Latitude & Longitude (decimal):||40.14028,-105.36584|
|Köppen climate type:||BSk : Cold semi-arid (steppe) climate|
Commodities (Major) - Quartz, Feldspar
Development Status: Occurrence
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
2 valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
541 - 4000 Ma
|Silver Plume Quartz Monzonite|
Age: Precambrian (541 - 4000 Ma)
Description: Pale yellowish- orange to pale reddish-gray, equigranular, fine- to medium-grained, biotite- muscovite quartz monzonite; some outcrops are gray to tan, medium- to coarse-grained porphyritic quartz monzonite that contains tabular microcline phenocrysts; c
Reference: Colton, Roger B. Geologic Map of the Boulder-Fort Collins-Greeley area, Colorado . U.S. Geological Survey Geologic Investigations Series I-855-G. 
1000 - 1600 Ma
|Granitic rocks of 1400-m.y. age group|
Age: Mesoproterozoic (1000 - 1600 Ma)
Description: Includes Silver Plume, Sherman, Cripple Creek, St. Kevin, Vernal Mesa, Curecanti, Eolus, and Trimble Granites or Quartz Monzonites; also, San Isabel Granite of Boyer (1962) and unnamed granitic rocks
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052. 
1600 - 2500 Ma
|Paleoproterozoic crystalline metamorphic rocks|
Age: Proterozoic (1600 - 2500 Ma)
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529.