Wildfires 101

Although the US wildfire season this year doesn’t seem quite as intense as prior ones, we thought this excellent primer…

Limestone speleothems (var. stalactite) hang from the ceiling of Glenwood Caverns, Glenwood Springs, Colorado. Photo credit: Vince Matthews for the CGS.

115th Annual AASG Meeting, Glenwood Springs, Colorado

The 2023 Association of American State Geologists meeting—hosted by the Colorado Geological Survey—takes place in Glenwood…

Matt Morgan on a cold day in the field at Titanium Ridge, Elbert County, Colorado, February 2019. Photo credit: Mike O'Keeffe for the CGS.

Introducing our new Director

Matt Morgan, Colorado Geological Survey, Director and Colorado State Geologist, Red Rocks Park, Morrison,…

Helicorder trace from Trinidad seismometer station, December 2019. Photo credit: CGS.

CGS Seismic Stations

Early History The Colorado School of Mines first acquired and installed a single three-component seismograph in the…

A 3610 g slice of the Bear Creek meteorite being held for scale that was formerly in the Jurgen Nauber Meteorite Collection (JNMC) in Zurich, Switzerland. Photo credit: Peter Marmet.

Tale of the Bear Creek Meteorite, Jefferson County, Colorado

By Matthew Morgan, Deputy Director, Colorado Geological Survey and Gary Curtiss, Lakewood geologist and meteorite collector A…

Aggregate quarry near Durango, Colorado. Photo credit: Mike O'Keeffe for the CGS.

IS-84 Colorado Mineral and Energy Industry Activities 2020-2021 – bibliography

Every year, the CGS Minerals section prepares a comprehensive survey of the mineral and energy industries across the state. The…

Check dams along drainage ditch, Clear Creek County, Colorado. Photo credit: Colorado Geological Survey.

Case Study: stormwater

Stormwater runoff is excess water associated with a rain or snow storm event that flows over the…

MS-51 Interpretive Geothermal Gradient Map of Colorado (detail)

Case Study: geothermal gradient

The CGS has long been involved in researching the characteristics of geothermal energy across the state,…

Tree trunk with up-stream face scoured by debris flow, Paradise Acres, Huerfano County, Colorado, September 2018. Photo credit: Jon Lovekin for the CGS.

HAZ-2021-01 Post-wildfire Hazards

Noting that we were getting hundreds of search hits on a previous version of an info-brochure that we originally published…

Detail from one of over 600 Denver Basin geophysical and lithological logs included in the ON-OF-78-08M digitization project. Photo credit: Colorado Geological Survey.

New GIS data and maps

For those of you who are subscribers to the CGS announcement list, we want to direct your attention to a…

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

Recent STATEMAP quadrangles

The CGS actively participates in the STATEMAP portion of…

Surface operations at the Climax molybdenum mine, Lake County, Colorado, 2009. Photo credit: Vince Matthews for the CGS.

A few new publications

For those of you who are recent subscribers to the CGS mailing list, we wanted to direct your attention to…

Avalanche snow with disturbed vegetation in runout zone. Photo credit: Colorado Geological Survey.

The Snowy Torrents

Here in Colorado, avalanche season is not over yet, and it’s been another deadly one with 26 fatalities so far…

Mining town, Eureka, San Juan County, Colorado, circa 1900. Photo credit: William Henry Jackson.

Re-introducing: Historic Metal Mining Districts

As the reconstruction of our website continues, we recently redeployed a popular package of information that was compiled and made…

While Glendon Rewerts begins the excavation that will host the site, Kyren Bogolub documents the installation gear: the Guralp CMG-3T seismometer in front, and the solar-powered Reftek RT130 digitizer in a Hardigg case with a Suntek solar panel behind. Photo credit: Ebru Bozdag.

Seismometer installed on campus

Mines students partner with the CGS to install seismometer on campus Colorado School of Mines geophysics students enrolled…

The classic afternoon thunderstorm forming over South Park can make field work ... complicated! Antero Reservoir Northeast quadrangle, South Park, Colorado, July 2017. Photo credit: Peter Barkmann for the CGS.

Recent STATEMAP quadrangles

The CGS actively participates in the STATEMAP portion of…

Colorado is well-known for the violence of summer afternoon thunderstorms that can be extremely dangerous, especially when at high-altitude. Photo credit: David Noe for the CGS.

Field Safety

It's field mapping time, and much of our staff are out in several different areas of the state, doing field work. A majority of the field work is part of the STATEMAP program—preparing geologic maps of particular quadrangles for the US Geological Survey sponsors of that nation-wide program.

Looking up the avalanche chute along Henson Creek in Hinsdale County, Colorado, April 2019. Photo credit: Jon Lovekin for the CGS.

Colorado Scientific Society lecture online

TITLE: Historic Avalanches in Hinsdale County, Colorado: Impacts to Lake City, old mining dams, and new evidence for the association…

The Arikaree River at Beecher Island in Yuma County, Colorado, February 2017. The groundwater level is indicated by the pooling of water in the bed of the otherwise dry river channel. Water will fill low spots in the channel that are deep enough to reach the water table. Photo credit: Jeffrey Beall, Wikimedia Commons

New Colorado Groundwater Atlas released

ON-010 Colorado Groundwater Atlas

OF-19-03 Geologic Map of the La Salle Quadrangle, Weld County, Colorado (detail)

OF-19-03 Geologic Map of the La Salle Quadrangle, Weld County, Colorado

As we continue to expand geological mapping coverage of Colorado, we recently uploaded another of our…

The end result of the current trenching on the Cheraw fault, near Arlington, Colorado, April 2019. Photo credit: Matt Morgan for the CGS.

Trenching the Cheraw Fault in Southeastern Colorado

One of the missions of the CGS is to better understand the various geological risks that face the residents of…

A uranium-rich zone in a sandstone of the Morrison Formation, Carnation Mine, San Miguel County, Colorado, January 2007. Photo credit: Colorado Geological Survey.

Colorado’s Uranium Deposits

[Ed: this document, written in 2011 by Jim Burnell, Ph.D., P.G. (former Senior Minerals Geologist, Colorado Geological Survey), provides an…

Slice of a pallasite meteorite, illustrating large olivine (peridot) crystals in a matrix of nickel-iron minerals. This specimen, known as the Brenham meteorite (DMNH EGT.23.0), is from Haviland, Kansas, and is ~25 cm wide. Photo credit: R. Wicker for the Denver Museum of Nature and Science.

DMNS Meteorite Collection

The Meteorite Collection of the Denver Museum of Nature & Science publication

Mount Garfield from Interstate-70, Mesa County, Colorado, March 2016. Photo credit: Larry Scott for the CGS.

Welcome to the final CGS/RockTalk web iteration

If you want to find out what's happening with the new CGS site, read here! Apologies for the incompleteness, it will improve on a daily basis, we promise!

Quote: Robert Frost, geohazards expert

Quote: Robert Frost, geohazards expert

Not only sands and gravels Were once more on their travels, But gulping muddy gallons…

Downtown Creede in 2010. Photo credit: Vince Matthews for the CGS.

Creede: The Last Boom Town

This RMPBS/Colorado Experience video explores the vibrant mining history of Creede, Colorado.

Uranium roll front hosted in Dakota Sandstone, Turkey Creek Road road-cut, Dakota Hogback, near Denver, Colorado. Photo credit: James St. John.

Geology of Uranium Deposits in Colorado

Uranium is a widespread and ubiquitous element. It has a crustal abundance of 2.8 parts per million, slightly more than…

Piping cave/soil arch in Qamf deposit, Loutzenhizer Arroyo, Delta County, Colorado, April 2007. Photo credit: David Noe for the CGS.

Collapsible Soils

By Jonathan White, Senior Engineering Geologist, Emeritus At the end of the 19th and beginning of…

Quote: Creative geologic ideas?

Quote: Creative geologic ideas?

No Geologist worth anything is permanently bound to a desk or laboratory, but the charming notion that true science can…

A Brief History of Colorado Through Time (Geology of Colorado)

One of the many fascinating videos from our geo-friends up the road at University of Colorado-Boulder:…