Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Structural analysis of Dehnow Anticline, an evidence for the effects of subsurface-transverse faults on fold geometry of Zogros Fold-Thrust Belt

Document Type : Original Research Paper

Authors
Ali yassaghi 1
Javad Bagheri 2
1 Department of Geology, Tarbiat Modares University, Tehran, Iran
2 Department of Geology, Tarbiat Modarres University, Tehran, Iran
Abstract
NW-SE trending Dehnow anticline located between Hendurabi and Razak lineaments and in hangingwall of Mountain Front Fault (MFF), has prominent characteristics such as existence of thrust faults on either limb, box shape at depth and occurrence of two minor anticlines in en-echelon array. In this paper, structural geometry of the anticline and the effect of subsurface-transverse lineaments on its geometry are presented using field data, satellite images and available seismic-reflection sections. Fold style of the anticline is affected by Salt Hormuz series, as a regional detachment layer. The fault detachment fold style of the anticline has been analyzed using seismic sections and structural data. The effects of regional deep-seated transverse structures such as Hendurabi and Razak Lineaments on structural geometry of the anticline were also investigated. Accordingly, a NW-SE trending subsurface transverse-shear zone was inferred in region. This shear zone caused development of en-echelon array set of fractures and folds in the interior of the anticline and counterclockwise rotation of its axis. It is suggested that this transverse-shear zone is the southern continuation of Sabzpoushan transverse fault zone. NE-SW trending Hendurabi lineament which was conformed to have a sinsteral fault zone causes clockwise rotation of the anticline axis. No structural evidences on the effect of the Razak lineament have been recognized in Dehnow anticline.
 
Keywords
Detachment Fold
Zagros Fold-Thrust Belt
Subsurface-Transverse faults
Sabzpushan fault Zone
Dehnow Anticline

Subjects

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Scientific Quarterly Journal of Geosciences
Volume 16, Issue 62
Winter 2007, vol. 16, no. 62
Winter 2007
Pages 14-29