Not enough data to create a plot.
Try a different view from the menu above.
Aswan Governorate
ABSTRACT: The variable characteristics exhibited by reservoir induced seismicity (RIS) can be adequately explained by the reduction in effective in situ stresses, brought about by impounding. Vertical reservoir loading has negligible impact and the controlling factor is the horizontal stress condition at any depth. This stress condition can be imposed on the crust by geoid changes. Analysis by Mohr circles leads to the conclusion that the crystalline basement rocks frequently exist in a state of incipient failure, often tensile. INTRODUCTION Over seventy case histories of reservoir induced seismicity (RIS) are cited by Gupta (1992). The induced earthquakes range from shallow, less than 1 โ 2 km focal depth, to moderate crustal depths of 10 โ 12 km. A large majority of events appear to fall within the 4 โ 6 km depth range, which would place them within the crystalline basement rocks at levels not normally considered in dam site investigations. In a majority of cases, RIS commences with impounding and reaches a maximum at times of full supply level, or shortly after, Figure 1. In other cases, no direct correlation between water level and seismic activity is obvious, although a time lag is sometimes apparent in the association. Occasionally, the seismic activity does not commence until many years after the reservoir has been in operation: at Oroville Dam after twelve years; Aswan Dam after sixteen years; Hoover Dam after forty years. In yet other cases, it is the rate of water level change which correlates with the seismic activity. A notably large number of RIS sites occur in otherwise seismically "quiet" regions: locations such as the central China shield; the Indian Deccan; the African and North American shields. By contrast, large dams in the seismic zones of the Himalayas cause no apparent increase in activity.
- North America (0.28)
- Asia > China (0.24)
- Africa > Middle East > Egypt > Aswan Governorate > Aswan (0.24)
- Energy > Renewable > Hydroelectric (1.00)
- Energy > Power Industry (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (0.97)
Estimation of the Parameters of Seepage Through an Earth Dam
Chowhury, Mahmudul Alam (Kagoshima University) | Kunitake, Masato (Miyazaki University) | Kondo, Fumiyoshi (Miyazaki University) | Inagaki, Hitone (Kagoshima University) | Ogata, Hidehiko (Kagoshima University) | Saito, Masaki (Crown Engineering Co., Ltd.) | Kakuda, Itsuro (Nihon Suiko Consultant Co., Ltd.)
ABSTRACT The finite element method was applied for solving a seepage problem involving unknown parameter estimation by back-analysis. The experimental model was an old, superannuated Fukada earth dam. The model was assumed to be one of anisotropic, plane quadratic isoparametric elements and two-dimensional flow. The permeability through the saturated and unsaturated zones was back-analyzed by a trial and error procedure. To solve this problem a series of repeated calculations were carried out, taking various possible assumed parameter. Initially the difference between the measured and calculated seepage lines was found to be very large, and finally a negligible difference was obtained. INTRODUCTION An estimate of the distribution of the world's water supply based on the U.S. Geological Survey has indicated that only 0.05% is held on land and in the atmosphere, the rest existing Is ice caps, glaciers and oceanic salty water functioning as a reservoir in the natural hydrological cycle. Surface, ground and min water are the main important sources of fresh water for living organisms on land. Continual extraction of ground water has a disadvantage of lowering the ground water table and creating high salt concentrations undesirable for irrigation water. The concept of dam construction is very old, has been done since ancient times to make water reservoirs, diverting river courses, producing hydropower and for irrigation of agricultural land. The Aswan dam on the river Nile in Egypt is a good example of dam work this century. The Aswan dam has dramatically changed the agricultural sector in Egypt. Presently, the construction of dams for irrigation crop production has been receiving more attention as a means of increasing crop production to feed the overgrowing population of the world. Sometimes, long-established hydraulic structures such as embankments and dams develop leakage and other problems. Earth dams are constructed by simple excavation work to make water reservoirs.
- North America > United States (1.00)
- Asia > Japan (0.96)
- Africa > Middle East > Egypt > Aswan Governorate > Aswan (0.44)
- Geology > Geological Subdiscipline (0.37)
- Geology > Mineral (0.34)
- Food & Agriculture > Agriculture (0.88)
- Energy > Renewable > Hydroelectric (0.74)
- Energy > Power Industry (0.74)
- (3 more...)