Drilling complications identification in support of 1D geomechanical modeling in a compartmentalized sedimentary section and fractured Paleozoic reservoir

Introduction. At the considered filed, complications in the form of differential sticking, tight hole events and slack offs during tripping operations, as well as mud losses of various origin and intensity were recorded during drilling. In view of the fact that approaches to eliminate a given set of complications conflict with each other, drilling recommendations suggestion is extremely difficult for a given cross-section.

Aim. Approach for comprehensive analysis of drilling complications development as well as their causes identification using additional information not included in the standard geomechanical modeling workflow.

Materials and methods. The study was carried out for Miocene and Paleozoic sediments. The developed approach is complementary to the standard geomechanical modeling and is based on the additional data introduction: mud logging, information on the complication development process, physical and chemical parameters of the drilling mud.

Results. A geomechanical model for the considered wells is built, the mechanisms of different types of complications are identified and recommendations for drilling new wells are given.

Conclusion. Additional data introduction in support of geomechanical modeling provides valuable information on the causes of complications and allows for a substantial expansion of thedrilling recommendations list. 

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