الملخص

Petrographical study of Injana Formation showed that the sandstones are composed of quartz, feldspars, high proportion of rock fragments, other components and carbonate cement. The sandstones are textuarlly, mineralogically immature as lithic arenite. Petrographic criteria point out that a semiarid–semihumid climate had prevalied during deposition. The affinity to source area validate a back–arc tectonic environment for the source rocks, which was a sequal of the regional continental collision between the Arabian plate (Iraq) and Turkish, Iranian plate; with concomitant uplift and consequent increase in the erosional and depositional rates.