Strain and shortening amount analysis in the Asmari anticline, Khuzestan province
Subject Areas : Geoscience Fields in relation with Petroleum GeologyBabak Samani 1 , Abbas Charchi 2 , Narges Khatib 3
1 - Faculty of Earth Sciences, Shahid Chamran University of Ahvaz
2 - Faculty of Earth Sciences, Shahid Chamran University of Ahvaz
3 - Faculty of Earth science, Shahid Chamran University of Ahvaz
Keywords: Dezful embayment, Asmari anticline, Strain, Shortening, fold interlimb angle ,
Abstract :
The only outcrop of Asmari formation in the Dezful embayment is visible in the Asmari anticline. In order to estimate the strain parameters and shortening values, 26 geological cross sections were prepared perpendicular to the anticline axis. Based on the, interlimb angle measurements, the interlimb angles of the northern and central parts of the anticline show smaller angles than the southern parts. Determination of strain ratio (R) values indicates the strain values between 1.12 - 1.52. The zoning map of strain ratio values shows higher strain values in the northern and central parts of the anticline. Using geological cross sections and measuring the base length of the folded layer of Asmari formation (L0) and the straight length of the layer (L1), the percentage of shortening values were calculated in each section. The results show the occurrence of 1.8% to 12% shortening in different parts of the anticline. Shortening map of the Asmari anticline shows more shortening amounts in the northern and central parts of the anticline than the southern parts.
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