STRATİGRAPHY AND STRUCTURE OF THE SOUTHEASTERN PART OF PİRAMAGROON ANTİCLİNE, SULAİMANİ AREA, NORTHEAST IRAQ

Abstract

The Piramagroon anticline (or Pira Magrun Mountain) elongates directly to northwest of Sulaimani city, Northeast Iraq and its southeastern part contains two other anticlines, named Harmetool and Yakhyian anticlines in addition to their complementary synclines and many other smaller folds. The anticline has experienced intense search for oil in the last few years and a well is drilled to depth of 3000 meters without reaching oil or gas. In the present study, the southeastern part has been studied stratigraphically and structurally and the previous studies are critically reviewed which may help reveal the reason for absence of oil in the area. The stratigraphy of the anticline has been differentiated and Kometan, Gulneri and Dokan, Balambo and Sarmord formations are plotted on a geological map and stratigraphic column and the nannofossils are used for aging of intervals that their ages are no determined previously. The thickness of the Gulneri Formation is 2-4m and the nannofossils analysis showed that its age is Late Cenomanian-Early Turonian. Lithology and bedding styles of the Dokan and Upper part of the Balambo formations are very similar to Kometan Formation and they can be differentiated either by fossils or by using Gulneri Formation as marker bed. The outcrop of the Gulneri Formation is helpful for differentiation since it is soft and can be recognized easily in the field by its darker color. The structure of the anticline is relatively complex as it consists mainly of asymmetrical anticlines with southwest vergen in few places while it changes to overturned folds in others and are deformed by reverse fault. The anticlines are shaped by detachments on the Gulneri and Sarmord formations and other older soft rocks. The resulted anticlines have style of multi-detachment fold or multi-detachment faulted fold .