Designation and Study of Anticlines- Kurdistan Region-NE Iraq

Abstract

Iraq is located in the Western Asian continent particularly in the northern Arabian promontory. Iraq approximately lies in center of Middle East. The area of investigation cover northern and northeastern parts of Iraq-Kurdistan Region. Iraq and Kurdistan region are located in the northern Arabian Platform. The study area includes the northwestern extension of the Zagros Mountain range (the Zagros Fold and Thrust belt). Through study of Tectonic analysis, Stratigraphy, Geomorphology and satellite images; we try to constrain new classification with designation of the anticlines and compression stress orientation in Zagros fold belt. The northeastern and northern Iraq contain huge anticlines and synclines. They have been formed as a result of compression stress. These forces formed by collision of Arabia and Eurasian plates during Eocene-Miocene periods. Most of the anticlines characterize by double-plunging symmetrical to semi-symmetrical fold. The shield of the anticlines in the High Folded Zone mostly compose of carbonate sequence from Cretaceous formations. The core has Jurassic-Triassic formations. In the other hand the shield of anticlines in Low Folded Zones are Cenozoic formations. The plunging and terminate anticlines was caused by Cretaceous pre-tilting extensional normal faults. These fault become barriers in front of growing the anticlines longitudinally as example in Kosrat and Shakrok anticlines. The Cretaceous lateral facies change affected on the bend of anticline axis. The northwestern of Azmar anticline and southeastern of Surdash anticline seem to be En-echelon plunging; through this study we find out they are belong to one anticline. The Surdash-Azmar fold Axis shape is Bezier line while passing through facies change between Qamchuqa and Balambo Formations. The same phenomenon can be find in Aqra-Bekhme anticlines by facies change of Aqra-Tanjero formations. In this study, we try to make two or more anticlines to be show as one large anticline. In previous studies they split anticline into two or more anticlines because of having geomorphological features such as valley and lakes. However we try to show that valleys and lake are not barriers and not affect termination of the anticline as shown in Shirin, Bradost, anticlines are one individual anticline.