Showing papers in "Engineering Geology in 1976"

TL;DR: In this paper, the authors investigated the effect of increased vertical load and increased pore pressure on seismic activity in large reservoir-induced earthquakes and concluded that the induced stress changes are not sufficient to generate post-impounding earthquakes.

TL;DR: Faulting and seismicity associated with fluid extraction are attributed to differential compaction at depth caused by reduction of reservoir fluid pressure and attendant increase in effective stress as discussed by the authors, which leads not only to differential subsidence and centripetally-directed horizontal displacements, but to changes in both vertical-and horizontal-strain regimes.

TL;DR: In this paper, a study of the geodetic properties of underground mine deformation and fractures was carried out in the Witwatersrand system of South Africa, and the authors found that the foci of seismic events with magnitudes from less than 0 to greater than 3 are found mainly within tens of metres of the advancing stope faces.

TL;DR: In this article, the authors summarized the physical processes leading to the stimulation of seismic activity by underground explosions, fluid injection, and reservoir impoundment, and concluded that the materials must be pre-stressed to a substantial fraction of their breaking strength in order for seismicity to be induced.

TL;DR: In this paper, the authors investigated the cause of reservoir impounding earthquakes at Hsinfengkiang reservoir in Kwangtung Province, where the majority of earthquakes occurred in the deep water gorge close to the dam, concentrated within a northwest belt.

TL;DR: Following the McCormick County, South Carolina, local magnitude 43 earthquake on August 2, 1974, continuous seismic activity has been observed in the area The epicenters are located within 3 km from the Clark Hill reservoir.

TL;DR: In this article, an examination of earthquakes from eight reservoirs shows that earthquakes at six sites occur at preferred times in the semidiurnal tidal cycle, i.e., when tidal stresses are oriented to enhance the tectonic stress.

TL;DR: The Shivaji Sager Lake as discussed by the authors experienced a burst of seismic activity from September 1967 to January 1968 following the record water levels in the reservoir and included the earthquake of September 13, 1967 with magnitude 5.5 and the damaging December 10, 1967 earthquake of magnitude 6.0.

TL;DR: In this article, the authors examined the annual and cumulative catalogues of Canadian earthquakes prepared by the Department of Energy, Mines and Resources to determine if they contain examples of induced seismic activity caused by fluid injection in oil fields, by the impounding of water in large reservoirs or by mining.

TL;DR: The aftershocks clearly define a planar surface striking north-south and dipping west at 62° from the surface to a depth of about 12 km as discussed by the authors, which is consistent with known seismic history of this area.

TL;DR: The use of two-dimensional fourier transforms of reservoir topography allows substantial increases in the speed of computation of loading effects on layered elastic models of the earth and on porous fluid-filled models as discussed by the authors.

TL;DR: In this article, the Mohr failure criterion with Coulomb friction is used to show that both types of triggering are possible in a normal-fault regime in Lake Kariba (Rhodesia/Zambia).

TL;DR: The Nurek Reservoir is located in an area of high seismicity and the average of 5-6 earthquakes of (Russian energy class)K = 10 and 1-2 earthquakes ofK = 11 per year occurred in the vicinity of the reservoir as mentioned in this paper.

TL;DR: A persistent 10 km seismicity gap along the Calaveras fault appears to be related to the presence of the Leroy Anderson Reservoir as discussed by the authors, where a bridge crossing the reservoir near its southeast end has been severely deformed, apparently the result of tectonic creep.

TL;DR: In this article, the authors describe a 6-month period during which the longwall face of a coal mine moved horizontally some 800 ft. below the area defined by the seismic array.

TL;DR: Dunkerley et al. as mentioned in this paper found that landslide occurrence and long-term slope stability are both governed by the residual shear strength of the clay soils which weather from the Triassic shales of this area.

TL;DR: In this article, aftershocks of the August 1, 1975 Oroville, California, earthquake (M L = 5.7 ) were recorded by an 8-station field-seismic network, and the focal coordinates of 104 of these events were fitted by least-squares to a plane striking N07°W and dipping 59°W; the strike (but not the dip) of this plane is in good agreement with that (N09°W) obtained from a fault-plane solution for a large foreshock 8 sec before the main shock, and it agrees

TL;DR: The distribution of this activity, excluding swarm events, exhibits a spatial pattern similar to that recorded earlier by regional seismic stations, except that several events appear to be associated with the fault underlying the Rocky Mountain Trench in which the lake is formed as mentioned in this paper.

TL;DR: The case history and the research work in regard to the water-induced earthquakes at Hsinfengkiang reservoir, 160 km. northeast of Canton, have been reported elsewhere as mentioned in this paper.

TL;DR: Thill et al. as discussed by the authors used an acoustic logging method to evaluate the structural quality of a porphyry copper-molybdenum deposit for in-situ leaching, and the results indicated the deterioration in structural quality from the preblast condition, in which the rock already was badly fractured and weathered, to the more highly fractured postblast condition.

TL;DR: In this paper, the classical theory of shear melting induced instability can be evaluated by a combination of variational principles and numerical minimization techniques, which can be generalized to any system induced towards instability by an outside agency.

TL;DR: Dick and R.C.Dick as discussed by the authors proposed a depth vs. depth plot to evaluate the same data, with the borehole water depth plotted as a function of borehole depth, and showed that anomalies can be detected more easily, and installed within these zones.

TL;DR: In this paper, the authors show that the diminution of the strain energy of a reservoir rock foundation in consequence of the failure of joints may be equivalent to the energy released by an earthquake of magnitude 6.