International Science and Technology Journal

Formation water or saline water known as produced water is generated in great volumes in onshore and offshore oil and gas production. It is important to determine its physical and chemical properties because of they are representing as a function of different factors such as depositional environment, water types and water classification. This study highlights the nature of the formation water and its characterizations in the light of different parameters and factors, in two oilfields namely Sarir and Nafora for oil producing wells, and in five gathering centers in Sarir oilfield throughout the chemical analysis of sixty water samples to determine the physiochemical characterizations. The data obtained from the chemical analysis were used to classify formation water and to determine the environment of deposition using Sulin's system. The results revealed that the type of formation water in both two fields are belonging to CaCl2 type and deep marine environment. The Stiff diagrams of the studied formation water of Sarir field were constructed for five gathering centers and compared with different patterns of Stiff diagrams. Most of the studied water exhibits a similarity of these patterns, but some of them show slightly deviation, this may be attributed to the type of formation and the source of brine.