Barnett Shale Development Planning
The Company will rely heavily on the use of horizontal drilling and 3D seismic to plan and execute development of its Barnett Shale acreage position. A typical 3D seismic survey showing the structure at the base of the Barnett Shale is depicted on the above left image. “Red” indicates structurally higher position and “blue” represents lower structural position. This survey demonstrates the presence of both faults (yellow) and a karst feature at the northern edge of the survey. Surface locations of both horizontal and vertical wells and the corresponding horizontal well paths are shown. Horizontal well paths are configured to avoid intersection with these faults and karsts that can serve as conduits to the potentially water bearing Ellenburger formation below the Barnett. Depending upon the size of the area impacted by faults and karsts, vertical wells may be drilled instead of horizontals. Horizontal well paths are also oriented perpendicular to the projected direction of the hydraulically induced fractures created during stimulation with “slickwater” (fresh water with viscosity reducing additives) and sand proppant. These induced fractures are designed to connect with and expand the natural fracture system present within the Barnett Shale formation. The right image above depicts the difference between the vertical and horizontal well path in a cross-sectional view.

We believe an approach that effectively integrates geologic information, 3D seismic data, and drilling, completion and production data from Carrizo and competitor wells, is required to maximize the productivity, reserves and ultimately the profitability of the Barnett Shale.