论文部分内容阅读
False color Landsat ETM+ (bands 7, 4, 2 in RGB) and SRTM images of the El-Faiyum depression, Egypt, highlights major NE-SW faults and other lineaments trending NW-SE and N-S. Airborne magnetic data reveal some E-W subsurface faults which are not recognized on Landsat ETM+ and SRTM images. Ratio images (5/7, 3/1, 4/3) and (5/7, 5/1, 4) were used for lithological discrimination of different rock types. The El-Faiyum area is occupied by sedimentary rocks of Middle Eocene, Upper Eocene, Oligocene, Lower Miocene, Pliocene, Pleistocene and Holocene. Understanding the structural regime of El-Faiyum depression in the Western Desert of Egypt is significant in relation to the neotectonics of the Nile Delta and to the development of new communities west of the delta. The area is covered by Late Cretaceous, Middle to Late Eocene deposits, Oligocene deposits (comprising fluviatile sediments and basalt sheets) and Pliocene and Quaternary alluvium and sand deposits. New geological and structural maps were prepared at a scale of 1 : 100 000 using Landsat ETM+ and SRTM images coupled with extensive field work. The major structural trends are E-W, ENE, NS and NW-the same trends observed elsewhere in North Africa from NW Sudan to NE Egypt including north and central Sinai. El-Faiyum depression is a structurally-controlled tectonic basin, marked by northeast-striking faults along its northern margin. These faults are parallel to similar faults of the Syrian arc fold belt, which includes a group of related faults, folds, push-up structures, and basins. Qarun Lake is located in the northern part of El-Faiyum depression, at a right-step between two strands of the NE striking fault system. We have suggested elsewhere that El-Faiyum depression is a pull-apart basin related to extension between these mismatched strands of strike-slip faults. The E-W structures are probably related to the relative motion between south Europe and north Egypt and closure of the Neotethys. The continuation of these faults in the present area is only detected from magnetic and seismic studies. The question that needs to be raised is why these old structural features have been reactivated in recent times. Thus, the presence of these fault zones must be heeded in all development plans for El-Faiyum region.
False color Landsat ETM + (bands 7, 4, 2 in RGB) and SRTM images of the El-Faiyum depression, Egypt, highlights major NE-SW faults and other lineaments trending NW-SE and NS. Airborne magnetic data reveal some EW subsurface faults which are not recognized on Landsat ETM + and SRTM images. Ratio images (5/7, 3/1, 4/3) and (5/7, 5/1, 4) were used for lithological discrimination of different rock types. -Faiyum area is occupied by sedimentary rocks of Middle Eocene, Upper Eocene, Oligocene, Lower Miocene, Pliocene, Pleistocene and Holocene. Understanding the structural regime of El-Faiyum depression in the Western Desert of Egypt is significant in relation to the neotectonics of the Nile Delta and to the development of new communities west of the delta. The area is covered by Late Cretaceous, Middle to Late Eocene deposits, Oligocene deposits (including fluviatile sediments and basalt sheets) and Pliocene and Quaternary alluvium and sand deposits. New geological and structural maps were prepared at a scale of 1: 100 000 using Landsat ETM + and SRTM images coupled with extensive field work. The major structural trends are EW, ENE, NS and NW-the same Taken together in North Africa from NW Sudan to NE Egypt including north and central Sinai. El-Faiyum depression is a structurally-controlled tectonic basin, marked by northeast-striking faults along its northern margin. These faults are parallel to similar faults of the Syrian arc fold belt, which includes a group of related faults, we have suggested elsewhere that El-Faiyum depression is a pull-apart basin related to extension between these mismatched strands of strike-slip faults. The EW structures are probably related to the relative motion between south Europe and north Egypt and closure of the Neotethys. The continuation of these faults in the present area is only detected from magnetic and seismic studies. The question that needs to be raised is why these old structural features have been reactivated in recent times. for El-Faiyum region.