Inverted topography in the southeastern part of the Western Desert of Egypt

We present here a series of surficial geologic maps of 22,000 km(2) of the southeastern part of the Western Desert of Egypt showing 3084 bodies of wadi-floor sediment that have been inverted by erosion to form sinuous ridges capped by alluvial gravel, here deicribed as inverted wadis. These features represent fragments of one or more ancient drainage systems that developed at times when rainfall, and hence overland flow, was greater than it is today in this hyperarid region. While some of the inverted wadis were tributaries to a through-flowing river that followed the course of the modern Nile, others converge on what appear to have been internal closed basins west of the Nile. Several components of this ancient drainage system have yielded artifacts assigned to an Acheulian lithic tradition, but there is not yet enough stratigraphic information available to enable us to relate this ancient drainage system to any of the proposed scenarios of Nile evolution. (C) 2016 Elsevier Ltd. All rights reserved.