Accession Number : AD0484051

Title :   LOCAL SEISMIC MONITORING.

Descriptive Note : Final technical rept. 15 Jan 64-15 May 66,

Corporate Author : STANFORD RESEARCH INST MENLO PARK CA

Personal Author(s) : Westphal, Warren H. ; Lange, Arthur L.

Report Date : MAY 1966

Pagination or Media Count : 242

Abstract : Four, low-power, portable seismographs were constructed. From August 1964 to October 1965, these seismographs were used to record local seismic activity in eight geographical areas in the conterminous U.S. and seismic signals at regional distances from the LONG SHOT explosion in Alaska. The resulting data indicated that most seismic activity can be related to specific geologic structures and that the level of the activity is quite variable in time. Periods of activity in a specific geologic structure are usually accompanied by higher magnitude (4-5) earthquakes. Aftershock sequences of these larger magnitude shocks, at least in three cases observed in western Nevada, appear to terminate within a few hours or at the most a few days after the main shock.

Descriptors :   (*NUCLEAR EXPLOSIONS, ALASKA), (*SEISMIC WAVES, UNITED STATES), UNDERGROUND EXPLOSIONS, SHOCK WAVES, MICROSEISMS, INTENSITY, EARTHQUAKES, SEISMOGRAPHS, PORTABLE EQUIPMENT, FAULTS(GEOLOGY), STRUCTURAL GEOLOGY, EPICENTERS, ARIZONA, NEVADA, CALIFORNIA, UTAH, OREGON, DETECTION, NETWORKS, COMPUTER PROGRAMMING, ALEUTIAN ISLANDS, MONITORS.

Subject Categories : Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE