A Study of Biostratigraphy of Sinjar Formation in selected sections from northern Iraq

Abstract

Late Paleocene –Early Eocene algae and benthic foraminifera were identified
from the Sinjar Formation that crop out in three selected section from northern
Iraq. The selected sections: (Derbandikhan ,Qara dagh, Wara Mali has been
measured in the field and closely sampled to undertake details. A number of (131)
samples were collected illustrating all the lithological changes along the sections,
The limestone in the studied section is rich in algae and large benthic foraminifera,
The investigation of the thin sections allowed us to identify the (47 ) species of
foraminifera and (34) species of algae , Five biozones were distinguished for algae
which are :a- Amphiroa iraquensis range zone ,b- Trinocladus perplexus range zone
,c- Lithothamnium – Pagodaporella wetzeli –Lithoporella melobesides Assemblage
zone ,d- Cymopolia kurdistanensis- parkerella Sp.- Dissocladella deserta - Jania
Sp. Assemblage zone, e- Clypeina merienda –Distichoplax biserialis -
Mesophyllum Sp,.-Archaeolithothamnium cf dollonii Assemblage zone. Five
biozones were distinguished for large benthic foraminifera which are :- a-
Cuvillierina sireli – Cuvillierina vallensis - Cibicides nammalensis – Rotalia
trochidiformis Assemblage zone ,b-Miscellane miscella –Discocylina varians
Assemblage zone , c-Idalina sinjarica –Nummulites globulus –Spherogypsina
globula –Somalina Sp.- Alveolina globosa Assemblage zone, d-Orbitolites Sp. -
Assilina Sp.- Ovulites Sp.- Cribogoesella Sp, Assemblage zone, e-Opertorbitolites
transitorius range zone. The age of this formation is Late Paleocene-Early Eocene
in the studied section.