Detrital zircon grains of an igneous rock as seen through an incident light microscope. Photo credit: Martin Lindner. From: Költringer Geology November 21, 2023 Case Study: detrital zircon [ED: On the occasion of releasing a new dataset: ON-004-04D Data tables of detrital zircon U-Pb geochronologic analyses and trace element concentrations of select Cretaceous, Paleogene, and Neogene rocks, Denver Basin and Northeastern Colorado (Data) – v20231110 that features data on 10 samples tested from a…
Large 700-series Caterpillar mine hauling trucks at the Holcim Portland Cement plant in Florence Energy, General, Minerals, Publications April 13, 2023 IS-85 Colorado Mineral and Energy Industry Activities 2021-2022 The current annual Colorado Mineral and Energy Industry Activities report for 2021-22 is now available. Following up on the 2020-21 report, this report is based on 2021 production data with additional reported news from 2022. It provides a comprehensive snapshot of Colorado’s mineral resource…
Pierre Shale (gray) exposed along St. Vrain Creek in Weld County General, Geology, Publications March 16, 2022 Recent reports published OF-20-11 Alkaline Complexes of the Wet Mountains Area, Colorado: A Geological Summary, Bibliography, and Data Compilation of Critical Mineral Laboratory Results — With renewed interest in critical minerals driven by global demand and consequent shortages, the CGS funded a compilation of historical sample results and a…
Aggregate quarry near Durango Energy, Minerals, Publications February 4, 2022 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 2020-2021 report isn’t finished quite yet, but the comprehensive bibliographic list that it is based on is. This list includes state, local and federal government sources, as well as private…
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. Geology, Minerals, Publications June 3, 2021 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 handful of new maps and recently digitized analog data sets that we haven’t otherwise publicized. These include several important online GIS maps and downloadable data packages:…
Surface operations at the Climax molybdenum mine Energy, Geology, Minerals, Publications April 15, 2021 A few new publications For those of you who are recent subscribers to the CGS mailing list, we wanted to direct your attention to a handful of new publications that we haven’t otherwise publicized. We’ve been adding more in the last months, so stay tuned for another introductory posting: IS-82…
A uranium-rich zone in a sandstone of the Morrison Formation, Carnation Mine, San Miguel County, CO, January 2007. Photo credit: Chris Carroll (CGS). Energy, Minerals February 19, 2020 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 excellent narrative on the sources of uranium deposits on the Western Slope of Colorado. However, it’s not the whole story—there is fascinating new science research implicating biological/organismic activity underground that…
Mount Garfield from Interstate-70 General January 10, 2020 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!
Downtown Creede in 2010. Photo credit: Vince Matthews for the CGS. Geology, Minerals October 16, 2019 Creede: The Last Boom Town This RMPBS/Colorado Experience video explores the vibrant mining history of Creede, Colorado. In so many ways, the story of Colorado is the story of mining. The town of Creede in the south-central Rockies of Colorado stands as one of the last mining…
Uranium roll front hosted in Dakota Sandstone Energy, Minerals August 14, 2018 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 tin. Primary deposits of uranium tend to concentrate in granitic or alkalic volcanic rocks, hydrothermal veins, marine black shales, and early Precambrian age placer deposits. Secondary (or epigenetic) deposits of…
Diamonds in the rough, note the regular octahedral forms and trigons (of positive and negative relief) formed by natural chemical etching. Photo credit: Wikimedia. Minerals February 19, 2018 What are diamonds? Diamonds are formed from pure carbon, one of the most abundant elements on planet Earth. Diamonds, even from ancient times, have been sought for their extraordinary hardness (they are the hardest substance known) and their brilliance, especially in the colorless transparent gemstone variety. Ironically the other form of pure carbon…
IS-79 Colorado Mineral and Energy Industry Activities 2015-2016 Energy, Minerals, Publications February 18, 2017 IS-79 Colorado Mineral and Energy Industry Activities 2015-16 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…