Diagenetic processes affecting on the sandstone rocks in the upper part of the Kolosh Formation in Dohuk area- northern Iraq

Abstract

Sandstones petrographical study of the upper part of the Kolosh Formation (Paleocene)at the southern limb of Bekhair anticline in Dohuk city showed clues of the effect of multivariate diagenetic processes and identified eogenesis (bioturbation, glauconite and pyrite authigenesis), mesogenesis induced by the pressure and tempreture deformation as a result of tectonic activities in the area which are amplified the pressure, tempreture conditions accompanied with relative deep burial leading to development of (compaction, cementation, replacement and recrystallization). Finally as a response to tectonic effects, the rocks were exposed and telogenesis stage begins including (dissolution, alteration and calcite, iron oxides cementation).Most of the diagenetic processes occured in meteoric and burial pheratic water diagenetic environments.At the same time, more than one diagenetic process had an effect on the rocks but in different proportions.