AN ATTEMPT TO IDENTIFY SUBGLACIAL FAULT ZONES ON THE BASIS OF GPR SOUNDINGS IN GLACIERS OF SOUTHERN SPITSBERGEN - - A CASE STUDY

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7105-98-8 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 11, 19-26 pp, DOI: 10.5593/sgem2017/11/S01.003

ABSTRACT

According to the geological maps of southern Spitsbergen, faults commonly run parallel to the glacier valleys’ axis. General faults orientation is N-S and NNW-SSE. This may suggest, that the origin of glacier valleys is related to tectonics due to development of structural landforms on individual faults. The network of ground penetrating radar (GPR) profiles based on measurements on three glaciers of southern Spitsbergen: Recherchebreen, Hansbreen and Werenskioldbreen, was processed and interpreted for the presence of fault zone within their bedding. Discontinuities and geological thresholds were identified on GPR profiles within subglacial structure. Obtained results were correlated with fault zones designated on the geological maps and then three-dimensional models of geological subglacial structures for selected glaciers were built in the Petrel software. The fault zones were illustratively presented in 3D imaging. The analysis suggests, that part of the structures identified on the GPR profiles refer to fault zones system presented on the geological maps. It is planned to conduct similar analyzes for other glaciers in southern Spitsbergen. The further steps will aim to develop full three-dimensional geological model of the southern Spitsbergen, that will allow to select a potentially active tectonic fault zones within this area. They might be potentially important for basal conditions of certain glaciers.

Keywords: southern Spitsbergen, glaciers, fault zones