EARTH MOTION MEASUREMENTS.

Abstract

Several parameters of ground motion on two deep underground nuclear detonations (Evans and Blanca) are measured. Primary measurements included vertical acceleration and velocity in a deep hole over Evans zero, horizontal and vertical acceleration on the mesa surface, and horizontal surface strain. Additional data were obtained on vertical response spectra (reed gage), surface subsidence (liquid level), and aftershocks (geophone listening) (Report WT-1740). Despite the less than satisfactory over-all results, some conclusions can be drawn on the basis of the data obtained. Arrival time studies seem to confirm earlier indications of a high speed layer in the Area 12 mesa at 300-foot depth. This layer was found to preclude general conclusions as to propagation mechanism or amplitudes measured at the surface. Subsurface motions although very small were consistent with scaling methods applied to prediction of Hardtack-II events.

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1961
Accession Number
AD0611241

Entities

People

  • D. C. Sachs
  • L. M. Swift
  • W. M. Wells

Organizations

  • SRI International

Tags

DTIC Thesaurus Topics

  • Amplitude
  • Detonations
  • Geophones
  • Measurement
  • Measuring Instruments
  • Motion
  • Physical Properties
  • Spectra
  • Time Studies

Readers

  • Marine Hydrodynamics
  • Mathematics or Statistics
  • Seismology