Feb 282017
 

We have a free 8.5- x 11-inch (pdf) geologic map of Colorado containing Geo-Whizology of Colorado on the reverse side.

Free 8.5- x 11-inch  map of Colorado geology along with Geo-Whizology

Free 8.5- x 11-inch map of Colorado geology (front) along with Geo-Whizology (back)

Of course, we’re a bit biased, but we think Colorado has magnificent geology and it is beautifully displayed for all to see. The state holds many of the biggest, the best, the first, and the most diverse:

For instance, did you know: Continue reading »

Feb 172017
 
IS-79 Colorado Mineral and Energy Industry Activities 2015-16 (cover)

The current annual Colorado Mineral and Energy Industry Activities report 2015-16 is now available. Following up on the 2014 report, this report, based on 2015 production data, sketches a comprehensive overview of Colorado’s mineral resource production. Of note is the fact that total value of mineral and energy fuels production in Colorado for 2015 is estimated to be $13.43 billion, a 29% decline from the $18.8 billion production value in 2014. The decline was caused primarily by a precipitous decrease in oil and gas market prices which provide 70% of Colorado mineral resource revenue. Oil and gas production actually registered at all-time highs of 127.6 Mbbl and 1,709 Bcf, respectively.

Nonfuel mineral production — including metals, industrial minerals, and construction materials — posted a modest 3.9% increase in revenue. Increased production of crushed stone, cement, and sand and gravel aggregate accounted for the increase. With a 2015 production of 21,790 metric tons of molybdenum from two mines, Colorado is the largest molybdenum producer in the U.S. Although just one mine in the state publicly reported gold production in 2015, Colorado remains the third largest producer of the metal in the U.S. as it was in 2014.


Citation: Cappa, James A., Michael K. O’Keefe, James R. Guilinger, and Karen A. Berry. “IS-79 Colorado Mineral and Energy Industry Activities 2015-16.” Mineral and Energy Industry. Information Series. Golden, CO: Colorado Geological Survey, 2016.
Feb 062017
 

With all the precipitation in the Rockies this year (we’re at +153% normal snowpack at the moment), we thought we would re-release a publication that highlights at least one important aspect of Colorado snowfall — that is, the significant danger of avalanches. The Snowy Torrents: Avalanche Accidents in the United States 1980-86, compiled and written by Nick Logan and Dale Atkins and illustrated with Larry Scott’s fine pencil drawings, was first published in 1996. We still have a few hard-copies available and, because of that, yes, we do charge for the PDF download. However, Larry went back and re-made the PDF from the original publication file, producing a file that is far better than the rather poor digital scan we had offered previously.

The volume details 146 oft-times harrowing stories surrounding avalanches, the lives they claim, survivors and witnesses, along with assessments as to what happened, why it happened, and what could have been done to prevent loss of life and/or property. The authors are never judgmental, and their clear-eyed accounts contain a wealth of wisdom that will add to the knowledge-base of any winter backcountry enthusiast.


Citation: Logan, Nick, and Dale Atkins. SP-39 The Snowy Torrents: Avalanche Accidents in the United States, 1980–86. Special Publications 39. Denver, CO: Colorado Geological Survey, Department of Natural Resources, 1996.
Jan 312017
 

A collaboration between the CGS and the Denver Museum of Nature & Science (DMNS) has resulted in a new stratigraphic chart for the state of Colorado. This beautifully (offset-)printed 42″ x 39″ color chart was designed from the ground up to illustrate the Proterozoic to Holocene stratigraphy that spans the state’s many sedimentary basins. A collaborative effort led by Robert Raynolds and James Hagadorn, the chart builds upon the work of dozens of colleagues and updates Richard Pearl’s seminal 1974 stratigraphy chart. The chart leverages the community’s stratigraphic work in both the subsurface and outcrop, and depicts new geochronologic constraints for many units. To facilitate comparison of strata to external forcing factors, the chart employs a linear timescale. Each unit’s dominant depositional environment is depicted as are major mountain building events, erosional events, and regional unconformities. Printed on heavy-duty 100# coated cover stock, these rolled posters may be purchased from the CGS online bookstore. They will make a fine gift for geoscientists, rockhounds, or anyone interested in how Colorado’s magnificent landscapes came to be.



From the chart itself:

Colorado’s stratigraphy is dominated by gaps. The distribution of strata reflects the tectonic and climatic evolution of each of the region’s eleven basin areas, depicted in the map below. To foster comparison of these patterns, we have organized the stratigraphy using a linear timescale and illustrated where orogenic uplift has led to removal of strata or nondeposition. Not all orogenic features are illustrated on the chart. For example, some orogenies caused sediment ponding and accumulation in intermontane basins, such as during the Laramide in northwestern Colorado. In the past ~10 Ma, regional uplift has raised Colorado and has allowed the modern landscapes to be created due to erosion. The chart’s color scheme for stratigraphic units gives a sense of dominant lithologies and depositional environments across basins. Updates to this chart, as well as additional stratigraphic resources, such as stratigraphic and structural cross-sections, may be found at http://coloradostratigraphy.org. To learn more about the unit names on this chart, resources are available at the U.S. Geological Survey’s Geolex site. This chart scaffolds on the work of Richard H. Pearl’s 1977 compilation (Rocky Mountain Association of Geologists, Special Publication 2). With the exception of the Carboniferous and Permian periods, this data has been re-cast against the International Commission on Stratigraphy’s chronostratigraphic chart v. 2015/01, updated at http://stratigraphy.org.


Citation: Raynolds, R. G., and James W. Hagadorn. “MS-53 Colorado Stratigraphy Chart.” Stratigraphic. Map Series 53. Denver, CO: Colorado Geological Survey and the Denver Museum of Nature & Science, January 2017.
Jan 232017
 

The CGS’s Matt Morgan and Jon White were two of the co-authors on one of the top-ten Geological Society of America (GSA) 2016 book chapters and journal articles, this out of 600 papers. The article describes a comprehensive forensic analysis of the massive West Salt Creek rock avalanche that occurred in late May 2014 in western Colorado (USA). The analysis relied on large-scale (1:1000) structural mapping accomplished via high-resolution unmanned aircraft system imagery along with seismic data generated by more than twenty stations within approximately 500 miles (800 km) of the event. The avalanche was the largest mass-movement slope failure in the historical record of Colorado, and it killed three people, narrowly avoiding destroying a gas wellhead.


Citation: Coe, Jeffrey A., Rex L. Baum, Kate E. Allstadt, Bernard F. Kochevar, Robert G. Schmitt, Matthew L. Morgan, Jonathan L. White, Benjamin T. Stratton, Timothy A. Hayashi, and Jason W. Kean. 2016. “Rock-Avalanche Dynamics Revealed by Large-Scale Field Mapping and Seismic Signals at a Highly Mobile Avalanche in the West Salt Creek Valley, Western Colorado.” Geosphere 12 (2): 607–31. doi:10.1130/GES01265.1.