Lateral growth of qara dagh anticline, south of Sulaimaniyah city, ne Iraq : a structural-geomorphological study

الملخص EN

The qara dagh anticline is located south of sulaimaniyah city in the high folded zone of the zagros fold-thrust belt, within the outer platform of the Arabian plate.

it is about 116 km long with a nw-se trend.

the oldest exposed rocks in the anticline are of paleocene age and belong to the kolosh formation; whereas, the limestone beds of the pila spi formation form the flanks of the anticline.

the pila spi formation locally forms the carapace of the mountain giving whale-back nature to the anticline.

we have conducted in this work a structural – geomorphological study of the qara dagh anticline using existing features and form of the anticline, observed and checked by field work; different types of satellite images and updated geological maps (scale of 1: 100 000).

structural, geomorphological and stratigraphic data confirm the lateral growth of the anticline in a nw direction, complemented by the presence of: fork-shaped valleys, axial valleys, radiated valleys, abandoned alluvial fans, and the presence of water and wind gaps.

the present study indicates that the qara dagh anticline was originally comprised of six smaller anticlines that exhibited lateral and vertical growth leading to the development of one major anticline.

the nw propagation of the six segments of qara dagh anticline is supported by the presence of two en-échelon plunges within the main anticline.

the rate of the lateral growth was higher than the rate of the incision of the streams; therefore, the streams were shifted around the tips of the segments; meanwhile abandoning the water gaps to wind gaps and development of new water gaps around the tips.