Paleostress analysis from brittle failure and minor structures in Dokan Area, Kurdistan Region, NE of Iraq .


Salim. H. Sulaiman Al-Hakari

Department of Geology, University of Sulaimani


Abstract

The study area is located within the high folded of the northwestern segment of the
Zagros Foreland Fold Thrust Belt in northeast of Iraq. Joints, mesofaults, veins and
stylolites were studied through seven stations in the Kosrat Anticline. The trend of
the fold and the strike of the strata are of NW-SE direction in accordance with the
main trend of Zagros folds.
New geological map and cross section of the study area were constructed. The
exposed rocks of the studied area range in age from Cretaceous up to the Eocene
included the following formations (Qamchuqa, Kometan, Shiranish, Tanjero,
Kolosh and Sinjar) Kometan and Tanjero formations was taken in consideration for
brittle failure analysis . The analyzed structural field data indicate that the
investigated area was subjected throughout its geological history to four stress
phases. First is primary compressive tectonic phase in the directions N-S, NE-SW
and successive phase in the direction ENE-WSW. The second compressive
tectonic stress in the direction NW-SE considered as a secondary phase. Third was
extension tectonic phase in the direction NE-SW which developed during the final
uplift stage of folding is normal to the major folds trend. The fourth is NW-SE
extension face considerate as extension stress related to the primary NE-SW
compressive stress.

Key Words:
Paleostress
analysis, Micro
tectonic analysis,
Brittle frailer
analysis


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