ABSTRACT: Horizontal drilling - A global perspective
Stark, Philip H. , IHS Energy Group, Denver, CO
Horizontal drilling has become a key technology to reduce costs and enhance recoveries from producing reservoirs. Commercial databases contain records on 20,029 horizontal wells from 64 countries. Through May 1999, 8,998 horizontal wells were reported in the U.S. and 7,955 were reported in Canada. More than 3,000 horizontal wells were reported outside of North America with Venezuela, Oman, Abu Dhabi, Nigeria and the U.K. reporting the most wells. The concept of horizontal drilling emerged in the 1920s. Early applications were limited to very short radius (~50 ft.) 'drainholes' in shallow, unconsolidated reservoirs. Enhanced technologies from the U.S.S.R., positive results with long-radius deviated wells and higher oil prices triggered renewed interest in horizontal drilling during the early 1980s. Pilot projects by Elf Acquitaine at Rospo Mare Field in Italy (1982), BP and ARCO at Prudhoe Bay Field (1984) and Oryx, Mobil, Amoco and UPRC in the Austin Chalk of Texas (1985-1987) demonstrated viability of horizontal drilling. From a base of 51 wells in 1987, horizontal drilling increased rapidly, expanded to most of the world's active producing provinces and peaked with about 4,000 wells during 1997.
The global geographic and geologic distribution of horizontal wells and horizontal drilling results in key reservoir types are characterized in this paper. Charts and maps are used to illustrate global horizontal drilling by completion year, country, geologic province, depth, geologic age, reservoir type and operator. Results for fractured chalks, fractured shales, reefs, tight sands and offshore fields are presented. Horizontal drilling, which fundamentally increases wellbore exposure to the reservoir, has delivered multiple benefits. Operators have used horizontal wells to revive economic production, to increase and speed recoveries from old fields, to reduce costs and to increase rate of return. All of these benefits are critical to operators who must compete in a period of excess oil supplies and low or volatile oil prices.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia