Accession Number : ADP204413

Title :   Discrimination of Earthquakes, Explosions, and Mining Tremors Using the Empirical Green's Function Method,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF EARTH ATMOSPHERIC AND PLANETARY SCIENCES

Personal Author(s) : Li, Y. ; Rodi, W. ; Toksoez, M. N.

PDF Url : ADP204413

Report Date : 14 AUG 1995

Pagination or Media Count : 10

Abstract : Using the empirical Green's function (EGF) method, we have estimated source time functions for earthquakes, industrial blasts, nuclear explosions, and mining tremors covering the magnitude range 0.9 - 6.6. The results show that, for events with magnitudes less than 2.5 or greater than 4.5, the time duration of the source time function can discriminate earthquakes from explosions. For large magnitude events source duration is longer for earthquakes than explosions, but at small magnitudes explosions have longer duration. For the remaining magnitude range (2.5 to 4.5) the earthquake, explosion and mining tremor populations overlap in the source duration vs. magnitude plane. However, the source time functions themselves display features that are indicative of event type, such as source directivity, spall phases, and multiple pulses in industrial blasts and mining tremors. Therefore, we conclude that source time functions inferred by the EGF method are potentially useful for regional event discrimination under a CTBT, and we recommend that further work be done to develop effective EGF-based discriminants for events in the magnitude range 2.5 to 4.5.

Descriptors :   *SEISMIC DETECTION, *MINING ENGINEERING, *ARMS CONTROL, *NUCLEAR EXPLOSION DETECTION, *SEISMIC DISCRIMINATION, *EARTHQUAKES, TIME INTERVALS, SYMPOSIA, BLAST WAVES, UNDERGROUND EXPLOSIONS, NUCLEAR EXPLOSION TESTING, TREATIES, GREENS FUNCTIONS, POLAND, SPALLATION.

Subject Categories : Government and Political Science
      Mining Engineering
      Seismology
      Seismic Detection and Detectors
      Nuclear Weapons

Distribution Statement : APPROVED FOR PUBLIC RELEASE