|
|
||||||||
DEPARTMENT OF GEOSCIENCES UNIVERSITY OF ARIZONA, TUCSON, ARIZONA 85721
SEISMOLOGICAL LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY, PASADENA, CALIFORNIA 91125
Abstract
The SH waves from 21 underground nuclear explosions at Pahute Mesa (NTS) were used to investigate tectonic release. The equivalent double-couple representation of the tectonic release, which was constrained by waveform modeling and the polarity of sP, is very similar for all the explosions. The average orientation is a right-lateral, strike-slip fault trending N15°W. Seismic moments were determined on the basis of comparisons with two western United States strike-slip earthquakes. BENHAM has the largest tectonic release moment (5.6 x 1024 dyne-cm) and STILTON (0.1 x 1024 dyne-cm) the smallest of the events studied. In general, the seismic moments increase with the size of the explosion, but the location of the explosion relative to previous explosions can strongly affect the tectonic release. The Pahute Mesa events can be separated into two populations: (1) events which are well separated (>4 km) from previous explosions, and (2) those events which are close (<4 km) to previous explosions. Those events which are close to previous explosions show a marked decrease in tectonic release. A least-squares fit of seismic moment to event size (as determined from the world wide, average ab amplitude) shows that the two populations are approximately parallel, but offset. The fact that the trends remain separated even at small yields (e.g., PIPKIN and SCOTCH) suggests that for Pahute Mesa there is not a threshold for tectonic release. Since spatial position gives the best separation of high and low tectonic release events, a volume model is favored for the source mechanism. The preferred model is motion on a system of faults and joints.
This article has been cited by other articles:
![]() |
T.-K. Hong and J. Rhie Regional Source Scaling of the 9 October 2006 Underground Nuclear Explosion in North Korea Bulletin of the Seismological Society of America, August 1, 2009; 99(4): 2523 - 2540. [Abstract] [Full Text] [PDF] |
||||
![]() |
Scattering from Tunnels near Sources and their Effect on Seismic Signatures of Explosions Bulletin of the Seismological Society of America, February 1, 2000; 90(1): 229 - 242. |
||||
![]() |
S. C. Myers, W. R. Walter, K. Mayeda, and L. Glenn Observations in support of Rg scattering as a source for explosion S waves: Regional and local recordings of the 1997 Kazakhstan depth of burial experiment Bulletin of the Seismological Society of America, April 1, 1999; 89(2): 544 - 549. [Abstract] [PDF] |
||||
![]() |
J. Zhang Source characterization using simplified waveforms: Tests on earthquakes and nuclear explosions in Xinjiang, China Bulletin of the Seismological Society of America, August 1, 1997; 87(4): 832 - 846. [Abstract] [PDF] |
||||
![]() |
R. L. Gibson Jr., M. N. Toksoz, and W. Dong Seismic radiation from explosively loaded cavities in isotropic and transversely isotropic media Bulletin of the Seismological Society of America, December 1, 1996; 86(6): 1910 - 1924. [Abstract] [PDF] |
||||
![]() |
H. J. PATTON Source models of the Harzer explosion from regional observations of fundamental-mode and higher mode surface waves Bulletin of the Seismological Society of America, June 1, 1988; 78(3): 1133 - 1157. [Abstract] [PDF] |
||||
![]() |
B. P. COHEE and T. LAY Modeling teleseismic SV waves from underground explosions with tectonic release: Results for Southern Novaya Zemlya Bulletin of the Seismological Society of America, June 1, 1988; 78(3): 1158 - 1178. [Abstract] [PDF] |
||||
![]() |
V. F. CORMIER Focusing and defocusing of teleseismic P waves by known three-dimensional structure beneath pahute mesa, Nevada Test Site Bulletin of the Seismological Society of America, October 1, 1987; 77(5): 1688 - 1703. [Abstract] [PDF] |
||||
![]() |
T. LAY Analysis of near-source contributions to early P-wave coda for underground explosions. II. Frequency dependence Bulletin of the Seismological Society of America, August 1, 1987; 77(4): 1252 - 1273. [Abstract] [PDF] |
||||
![]() |
T. LAY and J. L. WELC Analysis of near-source contributions to early P-wave coda for underground explosions. I. waveform complexity Bulletin of the Seismological Society of America, June 1, 1987; 77(3): 1017 - 1040. [Abstract] [PDF] |
||||
![]() |
R. W. BURGER, T. LAY, T. C. WALLACE, and L. J. BURDICK Evidence of tectonic release in long-period S waves from underground nuclear explosions at the Novaya Zemlya test sites Bulletin of the Seismological Society of America, June 1, 1986; 76(3): 733 - 755. [Abstract] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |