Geomechanical design of Shadegan oilfield in order to modeling and designing ERD wells in Bangestan formations

Document Type : Original Article

Authors

Department of Petroleum, Mining and Material Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran

Abstract

Geomechanical investigations of oilfields play a major role in wellbore stability analysis and design. Designing a geomechanical model in an oilfield formations is viewed as a crucial factor in successful drilling operations, hence this paper presents such study for Shadegan oilfield, an Iranian southwestern oilfield. Some geomechanical models were constructed with the aim of wellbore stability analysis for three candidate wells in this field. Primarily, the data were analyzed and geomechanical models were then provided using Techlog software yielding formation pressure profiles versus wells depth. Results showed an overpressure zone in Gachsaran formation. Further geomechanical investigations for Asmari formatiom were merely calculated due to lack of enough information. Achieved findings from the models demonstrated that existing stress regime in Asmari formation is normal tend to srike-slip. Wellbore stability analysis represented that the best orientation for directional and horizontal drilling is in northwestern direction. Constructed models were validated using field reports, paper documents as well as in-situ tests.

Keywords


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