Stratigraphic sequence of late Paleozoic era in Iraq

Abstract

The study put stratigraphic frame work of late Paleozoic era (Devonian – permian ) in Iraq, which include six formation from older (pirispiki, kaista, ora, Harur, ga'ara and chai Zairi) which are examined in eight borehole sections distributed in north, south west and western part of Iraq. These section have been compared with type section, which mostly lies in north Iraq. The studied sequences manily composed of siliciclastic and mixed ( carbonate – silliciclastic) which belongs to two megasequences each of them corresponding to the 1st order cycle of global sea level change. These megasequences are Kaskaskia sequence (late Devonian-early carboniferious) which represented by the pirispiki, kaista, ora and harur formation. The lower part of absaroka sequence (late carboniferious-permian) which represented by ga'ara and chaizairi formations. Time lines don’t match with the facies boundary and different from age of type section for some formations