Munroe Quarry near Livermore Geology, Hazards April 11, 2022 Case Study: Lykins Formation Small but significant areas of Colorado are underlain by bedrock that is composed of evaporative minerals. These are salts and sulfates that precipitate out of salt-concentrated surface waters. In the geologic past these minerals were deposited in shallow seas within closed or restricted basins where…
Hazards March 4, 2015 Land subsidence, a growing problem Deltares, an independent institute for applied research in the field of water and subsurface, hosted fifteen international subsidence experts to discuss subsidence problems worldwide at the annual meeting of UNESCO Land Subsidence working group. The video below features Gilles Erkens, subsidence expert…
Hazards June 16, 2011 Mine Subsidence Hazards in Colorado This video, produced by the CGS in 2011, examines the significant geo-hazards related to the long history of underground coal mining in Colorado.
Retaining wall settlement at the center of the image with the sorority houses in the background and the IM field in the foreground. Photo credit: T. C. Wait for the CGS.|The Rockwell clay mine area immediately south of the CSM campus along US 6 in 1977 before more recent reclamation as a golf course. The green area to the top left is part of the IM field where the subsidence occurred. Photo credit: Colorado Geological Survey.|DC resistivity survey crew from the engineering firm Zapata/Blackhawk laying out the multicore switch cables across the IM field area in 2008. Photo credit: T. C. Wait for the CGS.|Subsidence road damage near one of the sorority houses at CSM in August 2005. Photo credit: T. C. Wait for the CGS.|A drill-rig preparing boreholes for subsurface grouting under the IM field in August 2005. Photo credit: T. C. Wait for the CGS.|One of the several subsidence features in the IM field at the Colorado School of Mines in 2005. Photo credit: T. C. Wait for the CGS.|Figure from DC resistivity report from 2009 detailing some of the infrastructure Geology, Hazards April 26, 2005 Case Study: mine subsidence, CSM For decades, the west side of the Colorado School of Mines (CSM) main campus had subsidence issues related to historical mining activities. At one point, in the 1990s, one of the married student housing units in that area was so badly damaged that it was condemned. In the early…
A large sinkhole opened in January 2005 at the Ironbridge Development and Golf Course Hazards January 17, 2005 Case Study: Roaring Fork sinkhole [ED: This report from January 17, 2005 was written by Jon White, (Senior Engineering Geologist, Emeritus). Lightly edited for dated references it highlights a hazardous geological regime in the central Colorado Rockies around the Roaring Fork River Corridor.] Last week, while on the Western Slope, I was informed by…
West view of the 2003 sinkhole showing proximity to campus buildings. Sunlight Ski Area is on the left horizon. Roaring Fork River valley is in left middle background below the ski area and in front of first row of ridges. Photo credit: Jon White for the CGS.|South close-up view of sinkhole wall showing uniform silt sediments derived from windblown deposits (loess). CMC maintenance staff had started to fill the sinkhole with broken road-pavement waste. Photo credit: Jon White for the CGS.|Sample of the loess from the wall of the sinkhole. Photo credit: Jon White for the CGS.|The sinkhole site Geology, Hazards February 4, 2003 Case Study: Colorado Mountain College, Spring Valley In early February of 2003, a 24-foot-wide (7.5 m) sinkhole spontaneously opened on a soccer field at the Colorado Mountain College (CMC) – Spring Valley campus, about 10 miles (16 km) southeast of Glenwood Springs in Garfield County. The CMC physical plant maintenance staff back-filled the hole with road pavement…