Broadband discrimination studies. Technical report Nos. 5-8, 1 October 1979-30 September 1980

Technical Report · Mon Dec 29 04:00:00 EST 1980

OSTI ID:6615118

McEvilly, T V; Johnson, L R

A seismic array consisting of 9 stations arranged as three nested triangles with minimum spacing of 100 m and maximum spacing of 400 m was used to record the two NTS explosions, LIPTAUER in Yucca Valley on 3 April 1980 and COLWICK on Pahute Mesa on 26 April 1980. The distance of the array from the explosion was 1.9 km for LIPTAUER and 6.0 km for COLWICK. So far our analysis has concentrated on the COLWICK data. Preliminary results show that most of the energy in the first 5 sec of the seismograms is propagating at an azimuth and velocity which are consistent with generation at or very near the explosive source. The spatial coherence decays by a factor of 1/e at distances that range between 400 and 1200 m, depending upon direction and component of motion. In a direction parallel to the wavefront, the vertical and radial components are much more coherent than the transverse component, while all of the components have comparable coherence in a direction perpendicular to the wavefront. Coherence generally decreases as frequency increases. In addition to aiding our interpretation of elastic waves generated by an explosion, these array data should provide useful constraints on the possible mechanisms by which elastic waves can be scattered by inhomogeneities near the surface of the earth.

• Research Organization: California Univ., Berkeley, CA (USA). Seismographic Station
• OSTI ID: 6615118
• Report Number(s): AD-A-222133/1/XAB; CNN: F49620-79-C-0028; ARPA Order-3291
• Country of Publication: United States
• Language: English

Related Subjects

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
450300* -- Military Technology
Weaponry
& National Defense-- Nuclear Explosion Detection
DATA ANALYSIS
DETECTION
DISTANCE
DISTRIBUTION
DOCUMENT TYPES
EXPLOSIONS
MEASURING INSTRUMENTS
MOTION
NATIONAL ORGANIZATIONS
NEVADA TEST SITE
NUCLEAR EXPLOSIONS
PROGRESS REPORT
SCATTERING
SEISMIC ARRAYS
SEISMIC DETECTION
SEISMIC WAVES
SPATIAL DISTRIBUTION
US DOE
US ORGANIZATIONS