Analysis of Natural and Induced Fractures in the Barnett Shale: Mitchell EnergyCorporation, T.P. Sims No. 2, Wise County, Texas. Topical Report, January 1990-February 1992

摘要

Core and borehold image logs indicate that the Barnett Shale in the MitchellEnergy T.P. Sims No.2 well contains natural fractures. Fracture widths are typically 0.1 mm and appear to be filled with calcite mineralization. However, partial mineralization on fracture surfaces and dark areas along fracture traces seen on the FMS log indicate the presence of remnant apertures. The natural fractures have a mean strike of 114 deg and dip 74 deg to the southwest. Drilling-induced fractures measured on the FMS log have a mean strike of 54 deg and dip 81 deg to the northwest. Open-hole stress tests were also performed in the well. Five measurements of these very small hydraulic fractures have a mean strike of 60 deg and dip 87 deg to the northwest. These results apparently document a change in the stress field from the time the natural fractures formed to the present day.