Characteristics of Fractured Carbonate Aquifers in Wadi El Tarfa Basin, East El Minia Governorate, Egypt

Abstract

Wadi El Tarfa is one of the most promising areas in the Eastern Desert for land reclamations due to the availability of the groundwater resources from Eocene aquifers which are characterized by high potentiality and good quality. It extends southeast Beni Mazar and east Matai cities at the eastern fringes of El Minia governorate, Egypt. It lies between latitudes 28 ̊ 25 ̓ N and 28 ̊ 37 ̓ N and longitudes 30 ̊ 50 ̓ E and 32 ̊ 22 ̓ E. It is characterized by its large surface area that reaches about 4939 km2 which curved on the top of El Maaza limestone plateau and drains its surface water to the west direction toward the Nile River. The present study is focused mainly on the characteristics of Eocene fractured carbonate aquifers at Wadi El Tarfa and determining the available water resources. It has been achieved through detailed studies of the geomorphological, the geological, the hydrogeological and the hydrogeochemical settings. Geomorphologically, Wadi El Tarfa is subdivided into two main geomorphologic features; watershed areas and water collectors. The watershed areas include plateaus (El Maaza plateau and Southern Galala plateau) and the highly topographic features and mountains (Gebel El Ahmer, Gebel El Merier and Gebel Qurun Harhash). Water collectors contain (drainage network, morphotectonic depressions and flood plain). Wadi El Tarfa is subdivided into eight subbasins. It attains eighth order and its subbasins range from fifth order to seventh order. The evaluation of the flash flood hazard degrees of Wadi El Tarfa and its subbasins according to the morphometric ranking method reflected that subbasins (nos. 3 & 6), Wadi Abu Kibithat and Wadi Abu Sayyal are the most dangerous subbasins while Wadi Abu Thumaymat and subbasins (nos. 1 & 4) are the lowest hazards that reflect the good opportunity of recharging the shallow aquifers. Geologically, the stratigraphic succession of the exposed rock units at the study area ranges from Precambrian to Quaternary age. Especial attention is focused mainly on the rock units of the Middle Eocene age (Samalut and Maghagha Formations) which represent the water bearing formations at Wadi El Tarfa area. Four sections represent Middle Eocene rocks have been measured and described. Structurally, Wadi El Tarfa was affected by normal faults with NW – SE trend that originated after Eocene due to the tensile stress. Based on the field measurements, the geological map of Conoco (1987) and Landsat 8 images, the structural lineaments reveals two major trends NW – SE and NE – SW.