biostratigraphy and paleoecology of cretaceous/tertiary boundary in ...

VI
Abstract
The Cretaceous / Tertiary (K/T) boundary section, which crop out in the
studied regions are located within the High Folded zone (Dokan and Smaquli
area), Imbricated Zone (Sirwan valley, Barzinja and Qala Cholan area) in
Northeastern Iraq. Is extended in northwest-southeast direction as narrow trend
near and parallel to the Iraqi/ Iranian border. These units mainly consist of flysch
and flysch type successions of thick beds of clastic rocks of Tanjero / Kolosh
Formations in (Sirwan, Qulka and Gali sections) or flysch to molasses
Tanjero/Red bed series (Swaiss group) in (Kato and Qishlagh sections).
The study is specially focused on analysis of all the uncertain aspects of the
boundary zones, such as lithostratigraphy, biostratigraphy, paleoenvironment
reconstruction, paleoecology nature of contact, age determination, local and
regional correlation in order to answer many of the questions raised naturally
through different researches and studies since decades by different authors in
and outside Iraqi regions about lithostratigraphic, biostratigraphic nature of the
contact, age, paleoecology, paleoenvironment reconstruction, correlation with
regional, continental and intercontinental similarities.
The detail lithostratigraphic study achieved on the cropped upper most part of
the Upper Cretaceous successions (upper part of Tanjero Formation) in Sirwan
valley, Kato, Qishlagh And Qulka sections, with the lower most part of Kolosh
Formation and Red Bed Series of the Early Tertiary, while in the Gali section
(Smaquli area) the studied stratigraphic units include the upper part of Shiranish
Formation, Shiranish-Tanjero transition unit, Tanjero Formation and Kolosh
Formation.
Eight biozones were recorded in the studied area, based on identified
planktonic foraminiferal assemblages within uppermost part of Shiranish
Formation, Shiranish-Tanjero transition unit (Reddish to pale brown succession),
Tanjero Formation in Smaquli area (Gali section) and upper part of Tanjero
Formation in all other studied sections, and also four biozones are recorded