TECTONO-STRATIGRAPHIC EVOLUTION OF THE DOHUK

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TECTONO-STRATIGRAPHIC EVOLUTION OF THE DOHUK REGION,

KURDISTAN, NORTHERN IRAQ

Jamal Ali Hassan Doski

Submitted in accordance with the requirements for the degree of Ph.D.

Royal Holloway University of London

Department of Earth Sciences

2012

The candidate confirms that the work submitted is his own, and that appropriate credit has been given and reference has been made to the work of others.

Abstract

This study presents a detailed structural analysis of the Dohuk fold-thrust belt,

Kurdistan, Northern Iraq. It is based mainly on the results of field investigations, remote sensing analyses as well as numerical models of the detachment and faultpropagation folds. The Dohuk region is situated within the Zagros orogenic belt near the north-eastern boundary of Arabian plate in the Kurdistan region of northern Iraq.

The research area, between latitudes 36° 34` N - 37° 18` N and longitudes 42° 18` E -

44° 06` E, covers part of the simply folded Zagros fold-thrust belt as well as the Zagros imbricate zone.

Geological mapping was carried out over about 12 000 km 2 of the Dohuk fold belt and the surrounding areas. The field data combined with remote sensing interpretations were used to define the structural characteristics of the detachment folds and to determine the 2D/3D geometries of the stratigraphic units. A detailed geometric and genetic analysis of mesoscopic fractures was undertaken in the Tawake, Bekhair and

Dohuk anticlines. Five regional balanced sections were constructed across the Dohuk fold belt as well as detailed twelve balanced sections were constructed through the principal folds in the Dohuk - Zakho field area.

Deformation in the Dohuk fold belt is inferred to have occurred from the Mid Miocene through to the Present Day. The Dohuk fold belt is characterized by WNW-ESE striking doubly plunging, upright symmetric to slightly asymmetric detachment folds that expose Paleozoic through to Neogene strata. These folds are approximately 5 – 75 km long, 4 – 20 km wide and with a surface relief up to 2 km. Balanced sections indicate that shortening varies between 7.24 km and 14.73 km. The basal detachment is inferred to be within the Ordovician shale of the Khabour Formation above the Late

Precambrian crystalline basement. ii

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