SUMMARY REPORT OF STRONG MOTION MEASUREMENTS, UNDERGROUND NUCLEAR DETONATIONS
Subsurface and surface motion measurements were made on six underground nuclear detonations in the Oak Springs tuff of Nevada Test Site on Operation Hardtack II: Shots Mars ( approximately 13 tons), Tamulpais ( approximately -72 tons), Neptane ( approximately 90 tons), Logan ( approximately 5 kt), Evans ( approximately 55 tons), and Blanca ( approximately 19 kt). Treefield peak radial acceleration decreased as the inverse third or fourth power of slant range, as for Rainier. Particle velocities attenuated at a rate between the inverse square and inverse cube. Maximum radial and tangential subsurface stress varied as the inverse cube of radial range. Observed peak strain suggested attenuation at a rate between inverse cube and inverse square of range. Maximum upheaval at Blanca surface zero was about 25.5 feet: approximately 2.5 feet at 750 feet radial range; and 1.5 feet at 910 feet. Reed gage spectra indicated a shift of maximum energy to lower frequencies with increasing ground range. All components of surface acceleration followed an empirical equation of the form A(g) = 3 2 x 10/sup 6/ W/sup 0.7/ (kt R/sup -2/(ft). All components of surface displacement did not follow a comparable relationship. Displacement is more precisely predicted than acceleration. The velocity of the tuff was determined to be 5200 ft/sec, with the velocity of the underlying dolomite 11,700 ft/sec. The crust at Nevada Test Site has a velocity of 6.55 km/sec and a thickness of approximately 30 km. The top of the mantle has a velocity of 8.08 km/sec and dips eastward. (auth)
- Research Organization:
- California. Univ., Livermore. Lawrence Radiation Lab.; Stanford Research Inst., Menlo Park, Calif.; Sandia Corp., Albuquerque, N. Mex.
- NSA Number:
- NSA-14-015487
- OSTI ID:
- 4166968
- Report Number(s):
- ITR-1711
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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