Haynesville Shale Development Program – From Vertical to Horizontal

Abstract

Abstract The recently discovered Haynesville Shale is one of the largest natural gas fields in the world. It is a high – temperature, high – pressure (HTHP), aerially extensive basin gas with true vertical depths (TVD) ranging from 10,000 – 14,000 ft; temperatures of 300 – 350+ deg F; and pore pressures exceeding 10,000 psi. It represents an engineering challenge unlike other popular shale reservoirs including the Barnett, Fayetteville, and Bakken shales. In March 2008, EXCO started an aggressive development program in the Haynesville Shale reservoir on its East Texas/North Louisiana (ETX/NLA) acreage. The program had a six-month window to select a landing zone and the appropriate drilling and completion techniques. Those techniques were then refined and applied to the horizontal well development. The program included drilling six (6) vertical wells covering over 150 square miles to understand the reservoir rocks’ fracture properties and flow characteristics. It included whole cores; shale logging suites; hydraulic fracture design, operations, and diagnostics; chemical and radioactive tracers; flow-back characterization; diagnostic pressure testing and production evaluation. At the conclusion of the vertical appraisal phase, EXCO spud its first horizontal Haynesville well in DeSoto Parish by drilling the Oden Heirs 30-6H well. The well's initial potential exceeded over 22 MMCFD @ 7,800 psi. This success encouraged the company to continue the development program resulting in 16 of the top 25 wells in the basin. This paper outlines the program and the steps taken to achieve this accomplishment.