Universität zu Köln

Miller, R. McG., Krapf, C., Hoey, T., Fitchett, J., Nguno, A-k., Muyambas, R., Ndeutepo, A., Medialdea, A., Whitehead, A. and Stengel, I. (2021). A sedimentological record of fluvial-aeolian interactions and climate variability in the hyperarid northern Namib Desert, Namibia. S. Afr. J. Geol., 124 (3). S. 575 - 611. MARSHALLTOWN: GEOLOGICAL SOC SOUTH AFRICA. ISSN 1996-8590

Full text not available from this repository.

Abstract

The aeolian regime of the 100 km wide, hyperarid Namib Desert has been sporadically punctuated by the deposition of fluvial sediments generated during periods of higher humidity either further inland or well within the desert from Late Oligocene to Late Holocene. Four new Late Cenozoic formations are described from the northern Skeleton Coast and compared with formations further south: the Klein Nadas, Nadas (gravels, sands), Vulture's Nest (silts) and Uniab Boulder Formations. The Klein Nadas Formation is a trimodal mass-flow fan consisting of thousands of huge, remobilised, end-Carboniferous Dwyka glacial boulders, many >3 m in length, set in an abundant, K-feldspar-rich and sandy matrix of fine gravel. Deluge rains over the smallest catchments deep within the northern Namib were the driving agent for the Klein Nadas Fan, the termination of which, with its contained boulders, rests on the coastal salt pans. These rains also resulted in catastrophic mass flows in several of the other northern Namib rivers. The Uniab Boulder Formation, being one, consists only of huge free-standing boulders. Gravelly fluvial deposition took place during global interglacial and glacial events. The Skeleton Coast Erg and other smaller dune trains blocked the rivers at times. The low-energy, thinly bedded silt deposits of the central and northern Namib are quite distinctive from the sands and gravels of older deposits. Their intermittent deposition is illustrated by bioturbation and pedogenesis of individual layers. Published offshore proxy climatological data (pollens, upwelling, wind, sea surface temperatures) point to expansion of the winter-rainfall regime of the southern Cape into southwestern Angola during strong glacial periods between the Upper Pleistocene and Holocene. In contrast to deposition initiated by short summer thunder storms, we contend that the silt successions are river-end accumulations within which each layer was deposited by runoff from comparatively gentle winter rains that lasted several days.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Miller, R. McG. UNSPECIFIED UNSPECIFIED UNSPECIFIED Krapf, C. UNSPECIFIED UNSPECIFIED UNSPECIFIED Hoey, T. UNSPECIFIED UNSPECIFIED UNSPECIFIED Fitchett, J. UNSPECIFIED UNSPECIFIED UNSPECIFIED Nguno, A-k. UNSPECIFIED UNSPECIFIED UNSPECIFIED Muyambas, R. UNSPECIFIED UNSPECIFIED UNSPECIFIED Ndeutepo, A. UNSPECIFIED UNSPECIFIED UNSPECIFIED Medialdea, A. UNSPECIFIED UNSPECIFIED UNSPECIFIED Whitehead, A. UNSPECIFIED UNSPECIFIED UNSPECIFIED Stengel, I. UNSPECIFIED UNSPECIFIED UNSPECIFIED
URN:	urn:nbn:de:hbz:38-592167
DOI:	10.25131/sajg.124.0008
Journal or Publication Title:	S. Afr. J. Geol.
Volume:	124
Number:	3
Page Range:	S. 575 - 611
Date:	2021
Publisher:	GEOLOGICAL SOC SOUTH AFRICA
Place of Publication:	MARSHALLTOWN
ISSN:	1996-8590
Language:	English
Faculty:	Unspecified
Divisions:	Unspecified
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language CONTINENTAL FLOOD VOLCANISM; SKELETON COAST ERG; SOUTHERN-AFRICA; LATE-QUATERNARY; TSONDAB SANDSTONE; ORANGE RIVER; KUISEB RIVER; DEPOSITIONAL ENVIRONMENT; SOUTHWESTERN AFRICA; LATE PLEISTOCENE Multiple languages Geology Multiple languages
URI:	http://kups.ub.uni-koeln.de/id/eprint/59216