Throw partitioning across normal fault zones in the Ptolemais Basin, Greece

Author(s)
Efstratios Delogkos, Tom Manzocchi, Conrad Childs, Christos Sachanidis, Tryfon Barbas, Martin P.J. Schöpfer, Alexandros Chatzipetros, Spyros Pavlides, John J. Walsh
Abstract

The total throw across a fault zone may not occur entirely on a single fault strand but may be distributed onto several strands or may be accommodated by distributed deformation within or adjacent to the fault zone. Here we conduct a quantitative analysis of the partitioning of throw into three components, the throw accommodated by: (a) the largest fault strand; (b) subsidiary faults; and (c) continuous deformation in the form of bed rotation in sympathy with the fault downthrow direction. This analysis is applied to seven seismic-scale fault zones at outcrop resolution (maximum throw 50 m) that were mapped over a four-year period during open-cast lignite mining within the late Miocene-Pliocene Ptolemais Basin, West Macedonia, Greece. The analysis shows that the fault zones offsetting the lignite-marl sequence are more localized at higher throws with progressively more of the total throw accommodated by the largest fault strand. Normal drag, which can account for up to 12 m of the total throw, accommodates a lower proportion of the total throw on larger faults. It appears that initial fault segmentation is the main control on the degree of, and spatial variation in, fault throw partitioning.

Organisation(s)
Department of Geology
External organisation(s)
University College Dublin, Dimosia Epichirisi Ilektrismou, Aristotle University of Thessaloniki
Journal
Geological Society Special Publications
Volume
439
Pages
333-353
No. of pages
21
ISSN
0305-8719
DOI
https://doi.org/10.1144/SP439.19
Publication date
2017
Peer reviewed
Yes
Austrian Fields of Science 2012
105124 Tectonics
ASJC Scopus subject areas
Water Science and Technology, Ocean Engineering, Geology
Portal url
https://ucrisportal.univie.ac.at/en/publications/8c161008-e673-47bc-a400-f4a65e74646a