A drone shot of the layered Miocene basalts of the Grand Mesa Volcanic Field. The tan Green River Formation (Paleogene)—forming the hoodoos—is seen beneath talus accumulations at the base of the basalt flows, Lands End, Grand Mesa, Colorado, July 2017. Photo credit: Julian Chesnutt for the CGS.

Colorado Geological Survey

The Colorado Geological Survey (CGS) is a state government agency situated within the Colorado School of Mines. We provide a wide range of science-driven services—this website being one—bringing the best of Colorado geoscience to the public.

Our Mission

To help reduce the impact of geologic hazards on the citizens of Colorado; to promote responsible economic development of mineral and energy resources; to provide geologic insight into water resources; and to proffer sound geologic advice and information to a variety of constituencies.

More about the CGS

Stock groundwater well, Lost Creek Basin, Weld and Adams County, Colorado, August 2009. Photo credit: Colorado Geological Survey

ON-010 Colorado Groundwater Atlas

Groundwater—as a critical natural resource for Colorado—is the focus of this informative and data-rich online publication from the CGS. Building on our previous award-winning Ground Water Atlas of Colorado, it features a wide range of easily accessible data from a variety of sources.

Martin Marietta Aggregates in Jefferson County, Colorado, March 2013. Photo credit: Michael O'Keeffe for the CGS.

ON-007-01 Colorado Aggregate Resources Map

This interactive map includes the digital versions of our sand, gravel, and quarry aggregate publications for Colorado’s populous counties. The map consists of locations and resource ratings of these deposits to assist with land use planning and resource development.


Quick Links

Aerial mapping tools, Paonia Quadrangle, Colorado, August, 2013. Photo credit: Dave Noe for the CGS.

Map Portal

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SP-52 Messages in Stone cover


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MI-97 LiDAR-Based Map of the Cheraw Fault Scarp. Graphic credit: Colorado Geological Survey

GIS Data

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Looking northwest to Hells Kitchen from Ekkert, Colorado, towards Grand Mesa across the wide range of environments from

Colorado Geology

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Constellation Drive landslide, Colorado Springs, Colorado, August 2015. Photo credit: T.C.Wait for the CGS

Land Use Review

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ON-001 Colorado Earthquake and Fault Map


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Who we are and what we do …

About the CGS
Statewide map with POGI points.

Points of Geologic Interest

Given the spectacular geology that graces our state, we are happy to report that our new POGI map is now live! Check it out and let us know if you have any questions or additions!

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Anderson, Donna S., and Paul B. Haseman. MI-102 Golden Rocks: The Geology and Mining History of Golden, Colorado. Miscellaneous, MI–102. Golden, CO: Donna Anderson and Paul Haseman, 2021.

Newest Addition

Golden Rocks: The Geology and Mining History of Golden, Colorado

A detailed volume—written for the general public—that explores many fascinating features of the human and geological history of the town of Golden, the home to both the Colorado School of Mines and the Colorado Geological Survey. The authors, Donna Anderson and Paul Haseman generously made this comprehensive and well-researched work available for free to the public.

Our most popular publications :: (Please note that physical publications for sale are being migrated to our Amazon storefront in the next weeks. All free digital downloads will continue to be available here.)

Contact Us:

Colorado Geological Survey
Street and Mailing Address:
1801 Moly Road
Golden, Colorado  80401

telephone :: [+1] 303-384-2655

email ::

  • Use this form to ask us … anything!