STUDIES ON THE PLIOCENE - QUATERARY SEDIMENTS IN THE WESTERN FRINGES OF THE NILE DELTA - LOWER
NILE VALLEY STRETCH, EGYPT
BAHI ISSAWI, 1
SAYED M. AHMED, 1 RIFAIT A. OSMAN AND 1EMAD S.
SALLAM
Consulting Geologist: 16-Misaha St.,Dokki,Cairo;
1Zagazig University ,Benha branch,Faculty of sciences |
The westem fringes of the Nile Delta-lower Nile Valley stretch exposes a thick Cenozoic section in which the Pliocene sediments are still under much controversy. These sediments are classified into lower marine section including two units namely Kafr El Sheikh at base and Kom El Shelul at top. The newly recorded Kafr El Sheikh Formation is described here from its outcrops south of Ahu Sir for the first time inspite of its thick representation in the Nile Delta subsurface; Ca. l458m. The two marine units were deposited in a gulf basin extending from the Mediterranean to south of Aswan during the Early Pliocene. The retreat of the gulf water off the land of Egypt began by the Late Zanclean where the water stopped at Shakloufa area and further north till near Giza Pyramids depositing Kom El Shelul Formation.
A transitional unit namely Gar El Muluk Formation was deposited under brackish conditions between the lower two marine units and the overlying fluvial Wastani Formation when the sea completely withdrew off Egypt at the Late Pliocene. The brackish conditions of Gar El Muluk were a combination of the retreated marine water and a northerly flowing fluvial system filling local topographic depressions in the stretch between Gebel El Yatirn in the east and Wadi El Natrun in the west. The Quaternary sediments are classified into several units indicating alternating wet and dry phases.
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