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In situ stress field in the southeastern United States and its implication

Description: Published and unpublished in situ stress measurements and studies of earthquake focal mechanisms in the southeastern United States are reviewed. These data, which provide information on the relative magnitude and orientation of existing stress fields, are analyzed in relation to the geologic characteristics of the Southeast and are compared with data for other areas in the United States. The relation of the stress fields to observed geology and present-day tectonic processes is reviewed. Stress measurements reveal the existence of high horizontal stresses in the Appalachian complex. Different in situ stress states in the Appalachian complex, the Coastal Plain, and the stable interior region indicate different faulting mechanisms. Various techniques for determining in situ stress are consistent. 6 figures, 1 table.
Date: January 1, 1979
Creator: Stephenson, D.E. & Pratt, H.R.
Partner: UNT Libraries Government Documents Department

Geotechnical studies of geothermal reservoirs

Description: It is proposed to delineate the important factors in the geothermal environment that will affect drilling. The geologic environment of the particular areas of interest are described, including rock types, geologic structure, and other important parameters that help describe the reservoir and overlying cap rock. The geologic environment and reservoir characteristics of several geothermal areas were studied, and drill bits were obtained from most of the areas. The geothermal areas studied are: (1) Geysers, California, (2) Imperial Valley, California, (3) Roosevelt Hot Springs, Utah, (4) Bacca Ranch, Valle Grande, New Mexico, (5) Jemez Caldera, New Mexico, (6) Raft River, Idaho, and (7) Marysville, Montona. (MHR)
Date: January 1, 1976
Creator: Pratt, H.R. & Simonson, E.R.
Partner: UNT Libraries Government Documents Department

Instrumentation program for rock mechanics and spent fuel tests at the Nevada Test Site

Description: This report contains a discussion of an instrumentation and rock mechanics program recommended for consideration as part of the overall Lawrence Livermore nuclear waste storage program at NTS. It includes a discussion of (1) rationale for the heater tests, spent fuel facility evaluation, heated room tests, (2) recommended instrumentation types together with estimated delivery schedules, (3) recommended instrumentation layouts, (4) other proposed rock mechanics tests both laboratory and in situ, and (5) data acquisition and reduction requirements.
Date: August 1, 1978
Creator: Pratt, H.R.; Hustrulid, W.H. & Simonson, R.
Partner: UNT Libraries Government Documents Department

Earthquake damage to underground facilities

Description: The potential seismic risk for an underground nuclear waste repository will be one of the considerations in evaluating its ultimate location. However, the risk to subsurface facilities cannot be judged by applying intensity ratings derived from the surface effects of an earthquake. A literature review and analysis were performed to document the damage and non-damage due to earthquakes to underground facilities. Damage from earthquakes to tunnels, s, and wells and damage (rock bursts) from mining operations were investigated. Damage from documented nuclear events was also included in the study where applicable. There are very few data on damage in the subsurface due to earthquakes. This fact itself attests to the lessened effect of earthquakes in the subsurface because mines exist in areas where strong earthquakes have done extensive surface damage. More damage is reported in shallow tunnels near the surface than in deep mines. In mines and tunnels, large displacements occur primarily along pre-existing faults and fractures or at the surface entrance to these facilities.Data indicate vertical structures such as wells and shafts are less susceptible to damage than surface facilities. More analysis is required before seismic criteria can be formulated for the siting of a nuclear waste repository.
Date: November 1, 1978
Creator: Pratt, H.R. & Hustrulid, W.A. Stephenson, D.E.
Partner: UNT Libraries Government Documents Department

Earthquake damage to underground facilities

Description: In order to assess the seismic risk for an underground facility, a data base was established and analyzed to evaluate the potential for seismic disturbance. Substantial damage to underground facilities is usually the result of displacements primarily along pre-existing faults and fractures, or at the surface entrance to these facilities. Evidence of this comes from both earthquakes and large explosions. Therefore, the displacement due to earthquakes as a function of depth is important in the evaluation of the hazard to underground facilities. To evaluate potential displacements due to seismic effects of block motions along pre-existing or induced fractures, the displacement fields surrounding two types of faults were investigated. Analytical models were used to determine relative displacements of shafts and near-surface displacement of large rock masses. Numerical methods were used to determine the displacement fields associated with pure strike-slip and vertical normal faults. Results are presented as displacements for various fault lengths as a function of depth and distance. This provides input to determine potential displacements in terms of depth and distance for underground facilities, important for assessing potential sites and design parameters.
Date: January 1, 1980
Creator: Pratt, H.R.; Stephenson, D.E.; Zandt, G.; Bouchon, M. & Hustrulid, W.A.
Partner: UNT Libraries Government Documents Department