Kinematics and surface fracture pattern of the Anaran basement fault zone in NW of the Zagros Fold-Thrust Belt
2016 (English)In: International journal of earth sciences, ISSN 1437-3254, E-ISSN 1437-3262, Vol. 105, no 3, 869-883 p.Article in journal (Refereed) Published
The preexisting north-south trending basement faults and their reactivation played an important role during the evolution of the Zagros fold-thrust belt. The Anaran basement fault in the Lurestan region, NW of the Zagros, has been considered as a N-S trending basement lineament, although its surface structural expression is still debated. In this study, we use satellite images and field observations to identify and analyze the fractures in the sedimentary cover above the Anaran basement fault. Fracture analysis demonstrates that approaching the Anaran basement fault, the fracture pattern changes. The fractures association with reactivation of the deep-seated preexisting Anaran basement fault can be categorized in 4 sets based on their directions. The mean direction for maximum compressional stress is different between the fault- and fold-related fractures within and around the ABF shear zone. We estimated an orientation of N30±5° for the fault-related fractures and N45±5° for the fold-related fracture sets outside of the ABF shear zone. This difference suggests that the fold-related and fault-related fracture sets have been formed in different two stages of deformation throughout the area. The axial traces of some folds, especially the Anaran anticline, demonstrate a right-lateral offset along the ABF, such that, in central part of the Anaran anticline, the fold axis of this anticline is changed from its original NW–SE trend to approximately north-south trend of the ABF.
Place, publisher, year, edition, pages
2016. Vol. 105, no 3, 869-883 p.
Research subject Earth Science with specialization in Mineral Chemistry, Petrology and Tectonics
IdentifiersURN: urn:nbn:se:uu:diva-253628DOI: 10.1007/s00531-015-1209-8ISI: 000372612100009OAI: oai:DiVA.org:uu-253628DiVA: diva2:815277
FunderSwedish Research Council