Tectonic and Depositional History of Upper Cretaceous Tanjero Formations in Sulaymanya Area, NE-Iraq

Abstract

The basin of (Upper Cretaceous) Tanjero Formation is combined (tectonically) with that of the underlying Shiranish Formation and named Upper Cretaceous Zagros Early Foreland Basin instead of previous miogeosyncline and trench. In this basin Tanjero Formation is deposited in the near shore area in front of southwest advancing positive land of Iranian plate. This near shore area is called Upper Cretaceous Depocenter, whereas, the underlying Shiranish Formation a summed to be deposited in the deeper central part of the basin, which is called Upper Cretaceous Basin Center. The advancing of the hinterland (Iranian plate front) is very clear from southwest position changing of the shelf for about 20km. The shelf of lower sequence was near the Iranian border during Upper Campanian while it migrated to the area around Chuarta and Mawat Towns during middle Maastrichtian. It was inferred that most part of the formation is deposited by forced regression during collision of Iranian and Arabian plate. During this regression both flysch and molasses facies are deposited.

Stratigraphic Analysis of Azmir-Goizha anticline by Nannofossils

“…The nannofossil analysis proved that the soft lithology has same age of Gulneri Formation (Turonian). Many sequence stratigraphic models (such as Karim, 2004, Karim andSurdashy, 2006) are used for checking all new ideas of the present study.…”

Geology and Critical Review of the Upper Cretaceous Zagros Chalky Limestone (Kometan Formation) From Sulaimani Governorate, Northeastern Iraq

“…The present study does not agree with above timing of the Foreland basin since it had developed after deposition of Kometan Formation (during Campanian-Maastrichtian) ( Figure 15). This timing aided by many paleontological and sedimentological evidences such 500 m boulder and gravel conglomerate with red clastics that deposited during Maastrichtian and studied by Karim (2004), Karim, and Surdashy (2005) and Karim et al (2013).…”

“…The inter-beds clayey or marly materials are full of small pyrite crystals. There are agreement among researchers that the New Tethys sea (or ocean) is tectonically divided to oceanic and foreland basin episodes (Alavi 2004, Karim, 2004Karim, and Surdashy, 2005;Jassim and Goff, 2006). The tectonic position of Kometan Formation within two episodes is controversial since some authors put the formation in the foreland basin while others placed it on continental margin of oceanic episode.…”

Sedimentology of the Shiranish Formation in the Mergasur area, Iraqi Kurdistan

“…This formation represents the lower part of an Upper Cretaceous (Campanian and Maastrichtian) regional transgressive-regressive depositional sequence that flooded nearly all of Iraq (Dunnington, 1958). The basin of the Shiranish Formation combined tectonically with that of overlying Tanjero Formation in a single basin, which is called initial Zagros Foreland Basin (Karim & Surdashy, 2005;Karim et al, 2008). Despite its great scientific relevance for reconstructing upper Cretaceous events in Iraqi Kurdistan, this unit has only been locally studied (Ahmed et al, 2016).…”