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Paleodrainages of the Eastern Sahara - The radar rivers revisited (SIR-A/B implications for a mid-tertiary Trans-African drainage system)The images obtained by the Shuttle Imaging Radar (SIR)-A and -B systems over the southwestern Egypt and northwestern Sudan were coregistered with the Landsat images and the existing maps to aid in extrapolations of the buried paleodrainages ('radar rivers'), first discovered by SIR-A. Field observations explain the radar responses of three types of radar rivers, RR-1 (broad, aggraded valleys filled with alluvium), RR-2 (braided channels inset in the RR-1 valleys), and RR-3 (narrow, long, bedrock-incised channels). A generalized model of the radar rivers, based on field studies and regional geologic relations, shows inferred changes in river regimen since the large valleys were established during the later Paleogene-early Neogene. It is suggested that a former Trans-African master stream system may have flowed from headwaters in the Red Sea Hills southwestward across North Africa, discharging into the Atlantic at the Paleo-Niger delta, prior to the Neogene domal uplifts and building of volcanic edifices across the paths of these ancient watercourses.
Document ID
19860059436
Document Type
Reprint (Version printed in journal)
Authors
Mccauley, J. F. (Geological Survey Flagstaff, AZ, United States)
Breed, C. S. (Geological Survey Flagstaff, AZ, United States)
Schaber, G. G. (USGS Flagstaff, AZ, United States)
Mchugh, W. P. (GAI Cousultants, Inc. Pittsburgh, PA, United States)
Haynes, C. C. (Arizona, University Tucson, United States)
Date Acquired
August 12, 2013
Publication Date
July 1, 1986
Publication Information
Publication: IEEE Transactions on Geoscience and Remote Sensing
Volume: GE-24
ISSN: 0196-2892
Subject Category
EARTH RESOURCES AND REMOTE SENSING
Distribution Limits
Public
Copyright
Other