Petrography and Diagentic Processes in Sandstone of Injana Formation in Kand Fold, North Iraq


The sandstone of Injana Formation (Late Miocene) in Kand anticline consists dominently of carbonate rock fragments, among other types, followed by quartz, feldspars and mica. The ground mass is represented by higher amount of calcite cement in comparison to silica, clay and ferrigenous cements.Classification of the sandstones indicates their calclithic litharenite type. The source rocks embrace sedimentary, metamorphic and igneous rocks.The sandstones have been affected by early-diagentic events which mainly include carbonate cement and consequently subduced compaction. The processes of early-mesogentic diagenesis resulted in a decrease of primary porosity with a concomittant increase of secondary porosity during late diagenetic stage due to dissolution of carbonate cement.