Analysis of Data from Six Portable Strainmeters in Southern Nevada
Abstract
The report covers an analysis of secular strains over an annual cycle at six portable strain sites in southern Nevada as well as a study of the strain characteristics of signals from significant events recorded in the time interval 23 January 1970 through 31 July 1971. Measurements of quasi-static strains support the hypothesis that dynamic loading by the seismic waves from explosions and earthquakes trigger a local release of tectonic strain (a strain step). Furthermore, trends in the direction of strain steps appear to be related to regional tectonic strain. On the other hand, residual changes in strain of the order of 0.0001 m/m over an annual cycle do not fit any pattern that would suggest a long-term trend in the regional strain field, but appear to be peculiar to individual sites, or at most to subregions of the area covered by the six sites. Earthquake coupling factors among the six sites show nearly the same relative values as obtained from measurements of tidal coupling.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 31, 1971
- Accession Number
- AD0742240
Entities
People
- Robert C. Shopland
Organizations
- Teledyne Technologies