Jul 092017
 

Earthquakes strike suddenly, violently, and without warning. While Colorado is not as seismically active as some places, it does have a history of earthquake activity. Identifying potential hazards ahead of time and advance planning can reduce the dangers of serious injury or loss of life from an earthquake. Repairing deep plaster cracks in ceilings and foundations, anchoring overhead lighting fixtures to the ceiling, and following local seismic building standards, will help reduce the impact of earthquakes.

Six Ways to Plan Ahead

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Jul 032017
 

Nearly 100 potentially hazardous faults have been identified in Colorado. Generally, these are faults thought to have had movement within about the past 2 million years. There are other faults in the state that may have potential for producing future earthquakes. Because the occurrence of earthquakes is relatively infrequent in Colorado and the historical earthquake record is relatively short (only about 130 years), it is not possible to accurately estimate the timing or location of future dangerous earthquakes in Colorado. Nevertheless, the available seismic hazard information can provide a basis for a reasoned and prudent approach to seismic safety.

Faulting

Sudden movement on long faults is responsible for large earthquakes. By studying the geologic characteristics of faults, geoscientists can often determine when the fault last moved and estimate the magnitude of the earthquake that produced the last movement. In some cases it is possible to evaluate how frequently large earthquakes occurred on a specific fault during the recent geological past. Continue reading »

May 032017
 

The CGS recently installed the first of five new seismic recording stations that will collect information on seismic events around the state and the region. The CGS seismic network acts in conjunction with those maintained by the University of Colorado and Colorado State University, the Incorporated Research Institutions for Seismology (IRIS), and the US Geological Survey‘s National Earthquake Information Center (NEIC) — to provide near real-time earthquake detection. The addition of our monitoring capacity, the wider network allows the geoscience research community to better understand background seismicity in Colorado and better discriminate between natural and induced seismic events that may occur in the region.

The CGS already operates four other stations with Streckeisen STS-2 Broadband Sensors (capable of sensing ground motions over the frequency band 0.01 Hz (100 sec) to 15 Hz). They were part of a national consortium — USARRAY — that was a portable seismic network migrating around to different locations in the US several years ago. State-level organizations were allowed to ‘adopt’ some of the stations that were deployed within each state. The CGS purchased the four stations in 2010 — they are included on the map below as red boxes.

The set-up for a typical recording station includes the seismometer and its associated data recorder, a power system, and a communications system. The install site is carefully chosen for its relative acoustic silence — such that human-caused (road and air-traffic) and natural (wind, animal) noise levels are minimal at the relevant frequencies. The CGS cooperates with the Colorado State Land Board and the Colorado State Parks system in locating optimal sites for the stations in the CGS network. The particular station illustrated here is our Briggsdale Seismic Station #T25A-1 near Greeley, Colorado. Continue reading »

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 »