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Dakhla Oasis (25.5-degrees-N, 29-degrees-E) occupies a structurally localized depression at 90-140 m above sea level, approximately 1200 km2 in area, below a 300 m escarpment bordering the Libyan Plateau, Western Desert of Egypt. Semi-arid intervals of the Quaternary period generated eight sedimentary formations, separated by erosion during hyper-arid intervals. Sediments comprise three generations of colluvial/fluvial fanglomerates, two generations of tabular spring-laid clastic and chemical sediments, two generations of mound springs and basinal sediments of fluvio-lacustrine, evaporitic, pluvio-aeolian and aeolian origins. Discussion of these sediments is organized according to geomorphic region, from north to south, plateau, scarp and piedmont, lowland and cuesta plain.

Chronological evidence is restricted to many radiocarbon dates of Holocene cultural material associated with playa sediments (9-4.5 ka), a Th/U isochron age of approximately 62.0 +/- 7.6 ka for basinal evaporites, and two Th/U ages of approximately 176 and approximately 170 ka for a boulder of derived travertine. The regional Quaternary sequence is reconstructed from stratigraphic and geomorphic relationships of the sediments and erosion surfaces. It is broadly similar to sequences earlier reconstructed in the topographically similar Kharga Oasis region 150 km to the east, and Kurkur Oasis, 400 km to the south-southeast. Speculations on chronology and driving mechanism are offered in conclusion.