The Use of Gamma Ray Log Data to Compute and Study the Deposition of Shale Volume of Mishrif Formation in Middle and Southern Parts of Iraq

The shale volume is one of the most important properties that can be computed depending on gamma ray log. Mishrif Formation (carbonate formation from middle Cenomanian- early Turonian) was studied for regional area and southern parts Iraq. log data seventeen wells ( Kf-3,Kf-4, Ad-1,Ad -2,Dh-1, Bu-47, Ns-2, Ns-4, Am-1,Am-2,Hf-2,Hf-115,Mj-3,Mj-15, Su-7,Wq-15 Lu-7) distributed in study were used to compute Formation. From available considered wells, a isopach map obtained. indicates maximum thickness located at eastern part area. results CPI map, which using Techlog surfer software, show value (Su-7 well), while minimum (Hf-2well). According classification Kamel Mabrouk (2003), seems Shaly area, except Halfaya oil field as Clear top marker bed, appears shows trend toward northeast. variation divided into four zones.