Investigation into Lithological and Structural Modelling of Gachsaran Formation in Marun Oil Field Using Geostatistic Methods

Authors

1 Department of Geology, Shahid Chamran University of Ahvaz

2 M.S.C student of Geology, Shahid Chamran University of Ahvaz

3 N.I.S.O.C

Abstract

In the present study, the evaporitic Gachsaran Formation in the Marun oil field, using lithological characteristics and their variation, is evaluated. Its structural model was also provided using RMS software to understand the structure and reservoir management. The results indicated that the cap rock consists of anhydrite, marl, salt, bituminous shale and limestone. Among these, anhydrite and marl are main components. On the basis of lithological variation it is revealed that mudstone thickness increases key bed C to key bed F. According to lithological and textural diversity in the cap rock, a lagoonal-sabkha model can be proposed can be proposed for depositional environment. Lithological changes indicate alternative hot-wet to hot-dry climates during depositional time. At The dimensional structural model was constructed by the help of 2D-sciesmogram as well as drilled well information (well pick and well deviation data) of 390 wells. In this area, the presence of zone -6 at shallow depth in north eastern culmination can be ascribed to the northern fault while its deeper position in southern part can be related to southern fault. It seems the lithological characteristics of  Gachsaran Formation were not only attributed to these faults but also converted them into a resistant bar against reservoir oil migration. The present results taken from the model can be important in improving proficiency, decreasing the drilling risk and expenses, drilling time waste and reservoir management as well.
 

Keywords


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