Applications of Borehole Image Tools in Horizontal Gas Shale Wells for Completion Optimization

Camron Miller
Schlumberger

Operators have been drilling horizontal wells in gas shales for a number of years with favorable economic results. However, not all of these wells have met performance expectations. Wells that do not meet or exceed economic expectations need to be minimized, especially in today’s economic environment. This paper will explain how well placement and effective fracture stimulation are fundamental to the success of horizontal gas shale projects.

Today, most operators drill laterals within a specific zone that has the best reservoir and mechanical characteristics as defined by well log, core and seismic data. However, once this zone is selected, few of the lateral sections are placed and evaluated with technologies more advanced than a gamma ray or mud log.

This paper will demonstrate the applications of borehole images, while drilling, to optimize well placement, and/or after drilling, to drive perforation placement and stimulation staging within horizontal gas shale wells. Reservoir characteristics can change significantly along the length of a lateral and, for optimum results, the lateral section must be characterized and the perforation placement customized to account for these changes. Borehole images give a qualitative indication of mineralogy and allow one to identify, characterize, and define the orientation of bedding, faults and fractures. This information is being used to guide important completion decisions, whether focusing on natural fractures or avoiding faulted intervals observed along the wellbore. This high technology approach should lead to complex hydraulic fracture geometries, more fracture surface area and improved reservoir drainage.

AAPG Search and Discovery Article #90089©2009 AAPG Southwest Section Meeting, Midland, Texas, April 26-29, 2009