March 31, 2000

Estimated magnitudes of future earthquakes in Cache Valley and Northern Utah are high, according to a study released by the Utah Geological Survey (UGS). The largest expected earthquake on the Clarkston fault has estimated magnitudes between 6.9 and 7.4. The largest expected earthquake on the Junction Hills fault has estimated magnitudes between 6.8 and 7.3, while the Wellsville fault has magnitudes between 6.6 and 7.2.

The study, Paleoseismic Investigation of the Clarkston, Junction Hills, and Wellsville Faults, West Cache Fault Zone, Cache County, Utah, is the ninth report in a series of studies sponsored jointly by the Utah Geological Survey and the U.S. Geological Survey. These studies contain critical information about earthquake timing and recurrence, as well as information on fault displacement, slip rate, and geometry, which is used to determine potential earthquake sources and to evaluate long-term earthquake hazards presented by Utah faults.

All of the published "Utah Paleoseismic Special Studies" are available at the Natural Resources Map & Bookstore, 1594 West North Temple, Salt Lake City.