Earthquake Potential of the St. Louis District
Abstract
An analysis of geological factors was used in conjunction with a mathematical appraisal of seismological data to assess the earthquake potential within a portion of the central United States. These two approaches complemented each other since they used diverse sources to obtain their facts and premises. Earthquake potential was assessed using the concept of seismotectonic zones because of the difficulty in determining active faults in the central United States. Eight zones were resolved based on an analysis of geologic and seismic history, structural, tectonic, stratigraphic, and petrologic features, geophysical and seismological data, and midcontinent tectonic models. The resolution of the zones was an iterative process of geologically bounding the zones, assessing the historic seismicity, and determining the recurrence rates. Each of the eight zones was intended to be geologically and seismologically unique. Maximum credible (MCE) and operating basis (OBE) earthquakes were determined for each zone. The MCE was a judgmental value refined by comparing the geologic features, tectonic framework, historic seismicity, and recurrence characteristics of the various seismic zones. The OBE was based on a statistical evaluation of the seismic history and the certainty of earthquake occurrence.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1981
- Accession Number
- ADA098471
Entities
People
- Gerald B. Rupert
- Gregory L. Hempen
- John D. Rockaway
- Michael J. Klosterman
Organizations
- St. Louis District, U.S. Army Corps of Engineers