Stratigraphy of the Oligocene-Early Miocene successions, Sangaw area, Kurdistan Region, NE- Iraq

Abstract

Lithostratigraphy and biostratigraphy of the Darzila section from Low Folded Zone, Ashdagh Mountain, Sangaw area, Kurdistan Region, Northeastern Iraq, is investigated. Forty-three species from twenty-nine genera of large benthic foraminifera (LBF) in addition to non-foraminifera fossils such as echinoid fragments, bryozoan, red algae, green algae, bivalve, and coral are recognized from the studied section. Based on the recognized large benthic foraminifera, it is subdivided into six biozones: Nummulites vascus - Nummulites fichteli Assemblage Zone, Eulepidina dilatata - Nephrolepidina marginata Concurrent-Range Zone, Praerhapydionina delicata- Peneroplis evolutus- Concurrent Range Zone, Meandrospina anahensis - Austrotrillin asmariensis Interval Zone, Ammonia beccarii –Austrotrillina howchini Assemblage Zone, and Dendritina rangi- Rotalia viennoti Assemblage Zone. Both suggest an Oligocene to Early Miocene age. Each of these biozones represents certain lithostratigraphic units, which are Sheikh Alas, Baba, Bajwan, Anah, Jeribe, and Fatha formations. The recognized biozones were correlated with comparatively well-known biozones from other parts of the tethys region which showed a good comparison between the biostratigraphic zones established in this study with other studies.