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

Ullmann, Tobias; Nill, Leon; Schiestl, Robert ; Trappe, Julian; Lange-Athinodorou, Eva; Baumhauer, Roland und Meister, Julia (9. Dezember 2020): Mapping buried paleogeographical features of the Nile Delta (Egypt) using the Landsat archive. In: E&G Quaternary Science Journal, Bd. 69: S. 225-245

Abstract

The contribution highlights the use of Landsat spectral-temporal metrics (STMs) for the detection of surface anomalies that are potentially related to buried near-surface paleogeomorphological deposits in the Nile Delta (Egypt), in particular for a buried river branch close to Buto. The processing was completed in the Google Earth Engine (GEE) for the entire Nile Delta and for selected seasons of the year (summer/winter) using Landsat data from 1985 to 2019. We derived the STMs of the tasseled cap transformation (TC), the Normalized Difference Wetness Index (NDWI), and the Normalized Difference Vegetation Index (NDVI). These features were compared to historical topographic maps of the Survey of Egypt, CORONA imagery, the digital elevation model of the TanDEM-X mission, and modern high-resolution satellite imagery. The results suggest that the extent of channels is best revealed when differencing the median NDWI between summer (July/August) and winter (January/February) seasons (1NDWI). The observed difference is likely due to lower soil/plant moisture during summer, which is potentially caused by coarser-grained deposits and the morphology of the former levee. Similar anomalies were found in the immediate surroundings of several Pleistocene sand hills (“geziras”) and settlement mounds (“tells”) of the eastern delta, which allowed some mapping of the potential near-surface continuation. Such anomalies were not observed for the surroundings of tells of the western Nile Delta. Additional linear and meandering 1NDWI anomalies were found in the eastern Nile Delta in the immediate surroundings of the ancient site of Bubastis (Tell Basta), as well as several kilometers north of Zagazig. These anomalies might indicate former courses of Nile river branches. However, the 1NDWI does not provide an unambiguous delineation.

• Dokumententyp: Zeitschriftenartikel
• Publikationsform: Publisher's Version
• Keywords: Nile delta; landscape archaeology; paleogeography Egypt; Landsat Archive; Google Earth Engine; Normalized Difference Wetness Index (NDWI)
• Fakultät: Geschichts- und Kunstwissenschaften > Historisches Seminar > Alte Geschichte
• Themengebiete: 900 Geschichte und Geografie > 900 Geschichte ; 900 Geschichte und Geografie > 910 Geografie, Reisen ; 900 Geschichte und Geografie > 930 Geschichte des Altertums (bis ca. 499), Archäologie ; 900 Geschichte und Geografie > 960 Geschichte Afrikas
• Sprache: Englisch