A precarious rock above Manitou Springs started to move in 1995 after a period of wet weather. As an emergency measure Hazards June 20, 1995 Case Study: Rockfall – Manitou Springs [ED: This report from 1995 was written by Jon White, (Senior Engineering Geologist, Emeritus). It looks at a specific rockfall situation in the central Front Range town. ] Manitou Springs occupies a narrow valley where Fountain Creek emerges from the foothills northeast of Pikes Peak and west of Colorado Springs. The valley slopes are composed of interbedded resistant sandstone and conglomerates (i.e., gravelly sandstone), and weaker mudstones and shale. The outc...
Isoseismal map for the earthquake north-east of Denver - 9 August 1967 - MMI VII. (detail) Geology, Hazards August 9, 1967 Case Study: Denver – August 9, 1967 Major magnitude 5.3 earthquake shock in Denver One of the strongest and most economically damaging earthquakes to affect the Denver area in the 1960s occurred on August 9, 1967 around 6:30 AM, awakening and frightening thousands of people. This magnitude 5.3 earthquake, centered near Commerce…
Historical postcard "Prospecting in Leadville" General, Minerals March 11, 1909 Mines and Minerals: the early Survey While a number of brilliant men have in past years held the office of Colorado State Geologist, it is no disparagement to them to say that their work produced few tangible or lasting results. The fault was the state’s and her legislatures’ previous to that of 1907. Limited by niggardly…
Boulder oil field, 1915. Photo credit: C. L. McClure and the Denver Public Library. General, Geology March 29, 1907 Concerns about the new survey Regarding the Colorado Geological Survey (an article appearing in the Mining Reporter, March 1907): We note that one of our contemporaries, in recently commenting on the University bill creating a State Geological Survey of Colorado — the bill reported favorably on by the joint Senate and House mining committee —…
HAZUS simulation: 1882 Earthquake Geology, Hazards November 8, 1882 Case Study: The Big One It has been 140 years since “The Big One”: Colorado’s largest historic earthquake: November 7, 1882 – Magnitude 6.6. On Tuesday, November 7, 1882 at about 6:30 p.m. local Denver time, a moderately strong earthquake shook much of Colorado and parts of southern Wyoming and northeastern Utah. The following quote…