Scratching the surface

Author(s)
D. P. Le Heron, P. Dietrich, M. E. Busfield, C. Kettler, S. Bermanschlaeger, B. Grasemann
Abstract

Field observations in conjunction with aerial images from an unmanned aerial vehicle were used to create the first map of a glacial unconformity underlying the late Carboniferous Dwyka Group of South Africa. Crosscutting relationships reveal that the glacial unconformity at Oorlogskloof, in which flutes, grooves, and striae were ploughed into unconsolidated sand, formed in a three-phased process charting a periodic shift in the locus of subglacial erosion. The unconformity formed by a periodically decoupled ice sheet in a probable tidewater setting. This model contrasts with earlier views that the structures simply record progressive ice-margin liftoff during transgression, and they provide unique insight into the complex temporal development of a 300 Ma subglacial environment.

Organisation(s)
Department of Geology
External organisation(s)
University of Johannesburg (UJ), Université Rennes-I, University of Exeter
Journal
Geology
Volume
47
Pages
1034-1038
No. of pages
5
ISSN
0091-7613
DOI
https://doi.org/10.1130/G46590.1
Publication date
11-2019
Peer reviewed
Yes
Austrian Fields of Science 2012
105121 Sedimentology
Keywords
ASJC Scopus subject areas
Geology
Portal url
https://ucrisportal.univie.ac.at/en/publications/8298be40-f2e5-486f-b0f9-52721f929059