Some new play opener discoveries were reported in the Turgay Basin this year. Private SSM Oil LLP has made an oil discovery in the new Doshan Carbonates play in the Ketekazgan North field. The reservoir has been drilled by well Ketekazgan 18 at a depth of 3,070 m and is represented by a carbonate body in the Doshan Formation (Toarcian-Bajocian) that occurs on the slope of the Karatau Fault Zone at the South Turgay Sub-basinâs western margin. Previous discoveries in the Doshan plays were all in clastic reservoirs.  The carbonates were deposited in a Middle Jurassic lake and are thought to be an olistostrome of Paleozoic age. The carbonate bodyâs area is ca. 12 sq km, it is 56-150 m thick. The reservoir contains an oil pool, the extent of which requires further exploration/appraisal work.  Another private operator, Crystal Management LLP, reports a new reservoir/play for the Maybulak North discovery in the Zhilanshik trough in the north of the South Turgay Sub-basin. It is represented by Triassic to possibly Lower Jurassic deposits composed of brecciated carbonate and siliceous rocks, with low porosities (2.4%-4.0%) and permeabilities (gas permeability around 0.01 mD). The reservoir is fractured, it occurs at depths between 2,252-2,545 m. The reservoir tested a natural flow of oil at a rate of 1,006 b/d through 9 mm choke. Reservoirs of Triassic age were previously unknown in the Turgay Basin. Eroded Paleozoic formations from the rift basinâs flanks are believed to have been the source of these breccias.
Kazakhstan (South Turgay Sub-basin (Turgay B.)) Doshan