Depositional
history of Prenile, west of the Delta, Egypt, and its correlation with eastern
Mediterranean stratigraphy
Hesham M. Elasmar and Farouk M.
ElFawal
Dept. Geology, Damietta Fac. Sciences ElMansoura Univ. |
Two distinctive units are exposed in the sands
along the fluvial plain, west of the Nile Della. These units are related to different
NW-flowing fluvial regimes.
The lower unit represents a repetitive sequence of deposition by laterally accreted high
sinuous I meandering distributaries. It is characterized by relatively large -scale
sedimentary structures, finer, better sorted sediments, lower pyroxene content and the
development of a soil-like horizon along the muddy flood plain. This unit representing the
first climatic period of warm-wet conditions is related to the isotope stage 9 of global
warming was accompanied by high African monsoons which resulted in the development of
sapropel layer S10 in the Eastern Mediterranean basin.
The upper unit is a repetitive sequence of deposition by low sinuous distributaries having
ephemeral characters, and displaying upward-shallowing and energy reduction. This unit
includes relatively small- scale sedimentary structures, coarser, less sorted sediments
and higher pyroxene content indicating extensive erosion on the Ethiopian high lands. The
unit represents the Second climatic period of arid conditions related to the isotope stage
8 of global cold-arid climate. It is represented in the Eastern Mediterranean basin by the
oxidized sequence rich in iron oxides and impoverished in sapropels.
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