Study of the Relationship between Recently Induced Earthquakes and Water Level at the Northwestern Side of Lake Nasser in Aswan Region, Egypt

Abstract

Lake Nasser is situated in an area with a very non-recurring earthquake, and revealed the history of Egypt registered 5000 years ago. After seventeen years of filling the Aswan High Dam reservoir began a long series of earthquakes caused. The main shock, Ms. = 5.6, occurred on November 14, 1981, preceded by several factions, followed by a large number of aftershocks. Thirty-three years later, seismic activity remains, but is much lower in frequency and volume. The aim of this paper is to study the effect of the reservoir on the induced seismic and determine the coordination mechanism of some earthquakes that occurred in the northwestern part of High Dam reservoir. These investigations indicate that seismic activity occurred mainly along the Kalabsha fault and small parallel sectors, and there is a range of activities in the Khor al-Ramla area, about 40 km southwest of the High Dam. From 1982 to the end of 2017, seventy-five earthquakes with a magnitude of 3.5 ≤ M < 4.0 and 13 earthquakes of magnitude greater than or equal to 4.0 have occurred. It also shows that these earthquakes occurred during loading and unloading periods. This shows that the effect of the reservoir itself does not produce earthquakes, and there is no direct relationship between changing the daily rate and the magnitude of earthquakes. So it can’t be used as a predictor in the case of the Aswan reservoir, which is a unique reservoir in its behavior. The focused coordination mechanism of four different seismic zones in the west of Lake Nasser shows errors in striking the strike with a simple natural element. The P (pressure) and T (tension) stress axes are trending ESE–WNW and NNE–SSW, respectively.