English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

ed from Chumakov (1967) Marine deposits of Pliocene age have been discovered in the Nile Valley at a considerable depth below sea-level. These deposits have not only been detected in lower Egypt where the base of the upper Pliocene near Cairo has been established at —300 meters, but more recently in the High Dam area at Aswan. During the course of geological investigation in this area, lower Pliocene marine and estuarian sediments were encountered at —170 (and maybe —200) meters in a narrow incision into the bed of the paleo-Nile River. The overdeepening of this riverbed involved extensive erosion into a crystalline basement of gneiss and granite. The gradient of the bedrock floor of the buried valley of the Nile above Aswan indicates that the Pliocene sea formed a deep estuary in the Nile Valley, which penetrated upstream of Wadi Haifa, in the Sudan, some 1250 miles from the present seacoast. Cross-sections reconstructed from boreholes south of the Aswan Dam are illustrated in Figure 1. The lower part of the Pliocene sequence ( N 2 ^ ) was deposited in a salt water estuary revealing the maximum extent of the Pliocene transgression, which in the Mediterranean region is usually expressed by the Plaisancian. The middle transitional layer (N2 ), dated as Astian, shows a gradual change from oceanic conditions of sedimentation to continental. This series has only been found near the mouths of the east bank wadis. The Upper Series (Villafranchian) is represented by coarse alluvium in isolated patches on both banks of the Nile on the highest erosional surfaces at +160 to 200 meters elevation above the valley bottom of the paleo-Nile. The Quaternary fill (Qj to Q4) is exclusively alluvial and records the encroachment of semi-arid conditions.

Pliocene and Pleistocene Deposits of the Nile Valley in Nubia and Upper Egypt