الطباقية البالينولوجية وتحديد العمر والبيئة القديمة لتكوين بطمة في بئر قند-1 شمال العراق

Palynostratigraphy, Age determination and Paleoecology of Butmah Formation in borehole Kand-1 Northern Iraq

Eight samples (K1-K8) from borehole Kand-1 covering (190) meters thick stratigraphic section were palynologically studied. They yield (36) species of sporomorphs belonging to (24) genera, three species were expected to be new. The miospore species recoved in this study indicate late Triassic age (Norian) and characterized by the dominance of many species of bisaccate non-striate pollen such as: Alisporites australis, A. dunrobinensis, warepanus, Falcisporites tecovasensis, Pityosporites scaurus, Protodiploxypinus acutus, P. americus, Samaropollenites speciosus. In addition to monosaccate (Vesicate sporomorphs) represented by: Patinasporites densus, Vallasporites ignacii, Enzonalasporites vigens. The dominance of monosaccate pollen grains and the presence of the acritarchs, foraminiferal lining (acid-resistant inner coat) and fresh water algae in the lower part of stratigaphic section (K1-K3) indicate deposition in lagoonal environment with relatively high salinity and little supplies of fresh water. The increase of bisaccate pollen grains in the upper part of the sections (K4-K8) indicate deposition in relatively deeper environments (Inner shelf environment)