الفهرس 
CHAPTER ONEOnly 14 pages are availabe for public view
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Abstract
Paleoenvironmental interpretation and mineralogical studies of the exposed Quaternary Nile terraces in Wadi El Natrun area were investigated using collaborative techniques. Ten stratigraphic sections were collected for the present study. These sections are Hammra I, Hammra II, Hammra III, Quarry IV, Quarry V, Quarry VI, Sand sheet, Torrent VII, Torrent VIII and Torrent IX. Hammra I, II and III sections belong to the Middle Pleistocene, Quarry IV, V and VI sections belong to the Late Pleistocene, Sand sheet belongs to the Holocene and Torrent VII, VIII and IX sections belong to the Holocene (Recent).
Textural and mineralogical characteristics of the studied Quaternary point bar sediments revealed that they were deposited by defunct braided Nile channel. This is indicated by the nature of their cumulative curves which indicate that their transportation was dominated by saltation and traction. Mineralogically, the investigated heavy minerals are amphiboles, pyroxenes, zircon, tourmaline, rutile, epidote, kyanite, staurolite monazite and garnet. The ZTR index lies below 25 % indicating mineralogically immature sediments. The mineralogic and petrographic characteristics of the studied sediments revealed their derivation from older formations (Eocene, Oligocene and Miocene). Also, the obtained data revealed the occurrence of tufa on top of Hammra III section as a spring fed up by carbonate lake.
A flash flood fell of the November 4, 2015 and left remarkable economic losses and large number of victims in Wadi El Natrun depression. Regarding to salinization, the accumulation and precipitation of salt and natrun crystals affect drastically the fertile soils and turn it into bad land.
The Middle Pleistocene (Hammra I,II and III) sections are characterized by coarse sand and the internal structure of lamination and planar cross bedding indicating that these units were deposited by medium to high energy water current. Also, the occurrence of tufa as a spring fed up by carbonate lake indicates that they were deposited in highly evaporative environment with warm paleoclimatic and wet conditions as well. The Late Pleistocene (Quarry IV, V and VI) sections are characterized by medium sand and the internal structure of lamination, wedging shape and planar cross bedding which indicate that these units were deposited by medium energy water current. The Holocene Torrent (VII, VIII and IX) Sections are characterized by medium sand and the internal structure of lamination indicating that these units were deposited by medium energy water current.