Sinjar Anticline Northwest of Iraq: A Tectonic Geomorphological Study

The Sinjar Anticline (Mountain) is an outstanding structural and geomorphic feature in the northwestern part of Iraq. The anticline is a double plunging with almost E – W trend dividing the gently rolling plain in which it is developed into two parts, Al-Jazira Plain in the south and Rabi’a Plain in the north. The Sinjar anticline is asymmetrical with steeper northern limb (45 – 80)° and gentler southern limb (15 – 25)°, its length is about 80 km, whereas the width ranges between (9.25 – 12. 5) km. The oldest exposed rocks belong to the Shiranish Formation, whereas the youngest rocks belong to the Fatha Formation. Different geomorphological and structural forms were observed through interpretation of satellite images, geological and topographical maps of different scales, beside field observations. Among those forms are: Abandoned alluvial fans, radial, inclined, and cross-shaped valleys, whale-back shape, wind gaps, and parasitic folds. All these forms are good indications about the lateral growth of the anticline. Neotectonic measurements were carried to estimate the rates of upward and downward movements. These estimations were performed by measuring the elevation of the contact between the Fatha (Middle Miocene) and Injana (Late Miocene) formations at different selected locations on both sides of the anticline. Keywords: Sinjar anticline, lateral growth, neotectonic movements, wind gap, abandoned alluvial fans