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Paleoclimatic Evidence in Apparent 14C Ages of Saharian Groundwaters

Published online by Cambridge University Press:  18 July 2016

Christian Sonntag
Affiliation:
Institut für Umweltphysik, Universität Heidelberg, West Germany
Ulf Thorweihe
Affiliation:
Geologisches Institut der Technischen Universität Berlin
Jochen Rudolph
Affiliation:
Institut für Umweltphysik, Universität Heidelberg, West Germany
E P Löhnert
Affiliation:
Geology Department, University of Ife, Nigeria
Christel Junghans
Affiliation:
Institut für Umweltphysik, Universität Heidelberg, West Germany
K O Münnich
Affiliation:
Institut für Umweltphysik, Universität Heidelberg, West Germany
Eberhard Klitzsch
Affiliation:
Geologisches Institut der Technischen Universität Berlin
E M El Shazly
Affiliation:
Nuclear Materials Corporation, Cairo, Egypt
F M Swailem
Affiliation:
Middle Eastern Regional Radioisotope Centre, Cairo, Egypt
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Abstract

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Frequency distributions of more than 300 14C groundwater ages from various regions in northern and southern Sahara reflect the alternating sequence of humid and arid periods in the Sahara during the Holocene and late Pleistocene. A broad frequency maximum between 20,000 and 50,000 years bp indicates a long humid period. During this time span, the northern Sahara received rain from the Western Drift, which is concluded from a west-east decrease of deuterium and oxygen 18 of these groundwaters (continental effect). In the time-slice between 14,000 and 20,000 years bp, groundwater formation was significantly lower due to a cool and (semi-)arid period. In the Holocene, the Saharian climate is characterized by a sequence of dry and wet periods.

Type
Soils and Groundwater
Copyright
Copyright © The American Journal of Science

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