Determination of Wellbore Orientation in the Utica Shale of Southeast Ohio
March 16, 2016
The Utica Shale is fast becoming one of the premier shale plays in North America. As the number of wells drilled in the play is growing daily, optimizing well performance by nailing down wellbore orientation, landing point, and proper completion strategy is vital to the play’s success. In this presentation we will examine wellbore orientation. Most of the wellbores drilled in the Ordovician Point Pleasant member in the lower Utica have used an orientation similar to that of the shallower Devonian Marcellus wells. Wellbore image data, sonic anisotropy, and microseismic are used to determine the direction principal stress direction which is the driving factor in orienting the horizontal wellbore.
The wells used in this study, were consistent in their findings. The FMI data did not show any borehore breakout in the Point Pleasant. The fast and slow shear velocities in the dipole sonic logs did not differ significantly. Multi-well microseismic data indicated a complex fracture orientation.
Several wells were used in this analysis; they cover a range of counties – Belmont, Guernsey, Morgan, and Washington Counties, Ohio. All the wells supported the lack of a principal stress direction in the Ordovician, while supporting the NE/SW principal stress orientation in the shallower Devonian. The lack of a principal stress direction in the Point Pleasant allows for wellbores that align with lease dimensions permitting more efficient spacing of wells in a company’s leasehold. Since Ohio parcel distribution is complicated, the freedom of orienting a wellbore to best fit a lease is not insignificant.