Microfacies analysis and paleolimnology of latest Pleistocene - Holocene lacustrine sediments of Faiyum paleolake, Egypt

Abstract

The geomorphological and geological settings of Faiyum Depression make its lake sediments relevant to both the paleoclimate and paleohydrology of North Africa in general and Egypt in particular. Faiyum Depression is an endorheic basin that received fresh water from the Nile River during seasonal high flows throughout most of the late Pleistocene and Holocene. A detailed analysis of the textural and microfacies of lacustrine sediments were carried out. The sediment at the base of core F3-08, represent the last shirking phase of the previously huge late Pleistocene Lake phase with high beaches at c. 45m ASL. This phase represents ended by complete dissociation of the lake and prevailing of desert condition with accumulation of aeolian sand. An early Holocene freshwater mega-lake initially filled almost the whole Faiyum Depression and their beaches are existed at elevation of c. 25m ASL and since that time lake levels have fluctuated markedly leading to the small saline lake (Lake Qarun). During the Early and Middle Holocene, lake level changes were largely influenced by changing Nile floods driven by African monsoons and Westerlies affecting the African Nile headwaters. Detailed examination of sediment structures using high resolution microfacies differentiation in a continuous Holocene sediment core revealed the fine detail of sedimentological complexities. These are primarily attributed to changes in sediment supply, sedimentological conditions and sediment accumulation rates as the lake system responded to environmental modifications caused by both climate and by ancient people.