SEDIMENTOLOGY OF THE GOVANDA FORMATION AT GALI BAZA LOCALITY, KURDISTAN REGION, IRAQ

Abstract

The lithology of the Govanda Formation (Miocene) at Gali Baza locality, northeastern Iraq consists of massive conglomeratic bed at the base, grading upward to thin to medium bedded calcareous sandstone, sandy limestone, calcareous shale, and thin siltstone beds. The petrographic study of clastic and carbonate rocks, based on 21 thin sections, indicates that the major components are different kinds of rock fragments, quartz, altered feldspar and mica for the clastics and non- and/ or low-skeletal grains for the carbonates. The study showed that compaction is the most common diagenetic process affecting in the studied samples, appearing in the form of penetration between grains and grain deformation. Accordingly, it is suggested that the deposition of the Govanda Formation, in the studied Gali Baza section, had taken place in a littoral environment with terrigenous clastic supply.