Keywords : Tertiary

The Study of Folding in Cretaceous and Tertiary Formations in Bekhair Anticline Through Structural Contour Maps

Yousif Mohamad Baqir Al-Asadi; Abdulmutalib Hasoon Al-Matloubi; Mohamad Jalal Noori Al-Brifkani

Iraqi National Journal of Earth Sciences, 2012, Volume 12, Issue 1, Pages 73-94

Structural study was carried on the eastern part of Bekhair anticline
(Duhok section ) to test the folding phases within the formations related to Cretaceous and Tertiary period .This study adopted the structural contour maps in fold geometrical and structural analysis by construction of the Cretaceous and Tertiary formation contacts. The fold axes for the different structural contours were drawn .
The study found that there was an anticlockwise rotation of seven degree in the fold axis direction .This result supported ( or agreed ) with the results obtained from fold geometric analysis by stereographic projection ,which indicates that the studied fold were underwent more than one phase of folding .

Facies Analysis and Depositional Enviroment of Shiranish Formation in Bekhair Anticline, Dohuk Area, Northern Iraq

Rhadwan K. Al-Atroshi; Abdul Aziz M. Al-Hamdani

Iraqi National Journal of Earth Sciences, 2011, Volume 11, Issue 1, Pages 15-32

The microfacies analysis of the Shiranish Formation (Early-Late Maastrichtian) at the Bekhair anticline, Dohuk area, northern Iraq revealed that the succession is composed of alternation of seven microfacies, which are wholly micritic groundmass and rich in Planktonic Foraminifera. Based on the mode of vertical and lateral distribution, the present study deduced that this succession was deposited at Dohuk area by two environmental zones: upper-middle bathyal and outer shelf within one of the half-graben basin, which formed by Lisstric rifts. The latter was formed by the what so-called "piggy-back" basins at Foreland of the Arabian shelf. It is thought that the lithological and thickness variations at the bases of half-graben basin topography are due to tectonic irregularity