The Seismological Evidence for the Triggering of Block Motion by Large Explosions.
Abstract
The seismological evidence for the triggering of block motion by large nuclear explosions is evaluated. While ultimate interest is on the block motion at depth from large surface bursts, the paucity of data for such events makes it necessary to focus on contained explosions. The emphasis is on contained explosions at NTS since most U.S. data are from these events, but the nuclear experiments in Alaska, Colorado, and Mississippi are also discussed. The key parameter controlling block motion is found to be the level of tectonic stress in the vicinity of the explosion. It seems unlikely that significant block motions (large relative displacement outside the explosion produced shatter zone) were associated with post explosions except within a few hundred meters of the surface where the lithostatic pressure is low. Explosion aftershocks that occur for days after the event can cause block motions at considerable distances from the explosion. A quite cautious upper limit on the associated block motions observed for the megaton event BENHAM is about 50 cm at ranges up to 10 km or so.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1976
- Accession Number
- ADA047382
Entities
People
- D. G. Lambert
- T. C. Bache