Short contribution: Buried Canopic channel identified near Egypt's Nile delta coast with radar (SRTM) imagery

Abstract

Shuttle Radar Topography Mission (SRTM) data, with ground-based geologic investigations, define the geographic position of the relict Canopic channel in Egypt's NW Nile delta. Two sinuous channel segments south of Abu Qir Bay are observed on a radar image: a more sinuous trace (36 km in length) west of Idku lagoon, and an eastern one (~20 km), reaching the lagoon's southeast corner. Sediment cores recovered along channel traces show sand-rich deposits (to Ͼ 4 m thick) beneath the surface, in contrast with silty muds in areas away from channels. Historic and archaeological findings indicate that the Ptolemaic Roman city of Schedia once lay directly along the Canopic that channeled water from the 3rd to 2nd centuries B.C. until ~5th century A.D., after which Nile water was displaced to the east via Bolbitic and, later, Rosetta branches. Identification of buried, but well-defined, Canopic channels provides baselines for renewed archaeological exploration in this delta sector.

9.31 Dryland Fluvial Environments: Assessing Distinctiveness and Diversity from a Global Perspective

“…Remote sensing developments are enabling the detection and reconstruction of paleodrainage networks in more detail and over more extensive areas than has been possible previously, even in areas of widespread aeolian cover, thus providing context for interpretation of the development of the typically contracted, present-day drainage networks (e.g., Lancaster et al, 2000;Blumberg et al, 2004;Robinson et al, 2006;Stanley and Jorstad, 2006;Paillou et al, 2009;Craddock et al, 2010). Remote sensing developments are enabling the detection and reconstruction of paleodrainage networks in more detail and over more extensive areas than has been possible previously, even in areas of widespread aeolian cover, thus providing context for interpretation of the development of the typically contracted, present-day drainage networks (e.g., Lancaster et al, 2000;Blumberg et al, 2004;Robinson et al, 2006;Stanley and Jorstad, 2006;Paillou et al, 2009;Craddock et al, 2010).…”

Tracing Holocene channels and landforms of the Nile Delta through integration of early elevation, geophysical, and sediment core data

“…This was especially true for the coarser grain particles that deposited in the channel bed and on the river banks, whereas the finer sediment loads were carried by the overflowing waters away from the channels and deposited in the floodplains surrounding, or distant from, the river banks. In such settings, the grain size distribution of sediments within the river beds and on the river banks are largely dominated by coarser-grained sediments (sands and silty sands), whereas those within floodplains are largely composed of fine-grained silts and clays (Stanley and Jorstad, 2006; Thonon et al, 2007). With recurring River Nile floods, coarser-grained sediments accumulate and build up in the river bed and on the river banks to form natural levees that stand higher than the surroundings (Said, 1993).…”

“…These attempts (e.g. Ball, 1939; El Gamili et al, 2001; El Gamili and Shaaban, 1988; El Mahmoudi and Gabr, 2008; Quintanar et al, 2013; Sneh and Weissbrod, 1973; Stanley and Jorstad, 2006) utilized optical and radar remote sensing, geophysical surveys, and drill core sample analyses to identify segments of the historically cited paleochannels. In this study, we attempt to undertake the following tasks: (1) provide methodologies and procedures developed to extract the spatial distribution of paleochannels from detailed (1:25,000) topographic maps produced in the 1940s, (2) test the validity of the extracted paleochannel network using one-dimensional (1D) and two-dimensional (2D) geophysical survey analysis and drill core and borehole data, and (3) discuss the significance of our findings, and the potential applications and limitations for mapping paleochannels in deltas elsewhere.…”

Mapping buried paleogeographical features of the Nile Delta (Egypt) using the Landsat archive

“…He mapped linear structures, which presumably represent natural embankments of former rivers (levees). Since the end of the 1980s, satellite images (e.g., Landsat, SPOT, Corona, RapidEye) have been increasingly used to detect old river courses in the Nile Delta (e.g., Wunderlich, 1989;Marcolongo, 1992;Moshier and El-Kalani, 2008;Wilson and Grigoropoulos, 2009;Trampier et al, 2013;Ginau et al, 2017). Along with this, digital elevation models (DEMs) from the Shuttle Radar Topography Mission (SRTM; Stanley and Jorstad, 2006), as well as high-resolution data acquired by the TanDEM-X mission, have been used (Ginau et al, 2019).…”