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Title: Opportunities for horizontal drilling in Texas

Conference · · AAPG Bulletin (American Association of Petroleum Geologists); (United States)
OSTI ID:5572821

To date, horizontal drilling in Texas has been effective in achieving production increases where natural fracturing is significant, as in the Pearsall field of the Austin Chalk trend of south Texas. Projected average ultimate recoveries of 500,000 bbl of oil and 500 mmcf of gas per horizontal well compare with 75,000 bbl and 82 mmcf for vertical wells in that field. In addition to increasing production from naturally fractured reservoirs, horizontal drilling applications can enhance production where coning problems exist, where the reservoir zone is thin, where a gravity drainage mechanism exists, or where macroscale heterogeneity can be overcome to produce from complex, compartmentalized reservoirs. Major Texas reservoirs have been classified into 47 oil plays and 73 gas plays that are useful in evaluating the application of horizontal drilling. Geological character amenable to horizontal drilling is evident in at least 10 oil plays containing 144 reservoirs, more than two Bbl of proved reserves, and eight Bbbl of uncovered mobile oil. At least seven gas plays containing more than 124 reservoirs with cumulative production of more than 19.7 tcf are amenable to horizontal drilling. Tight gas reservoirs may benefit from multiple hydraulic fracture treatments from horizontal well sections drilled parallel to the minimum horizontal stress direction. Although play analysis defines general suitability, applications of horizontal drilling depend upon geologic, engineering, and, most importantly, economic assessments of specific prospects. Increased understanding of fractured reservoirs and of scales of reservoir heterogeneity will enhance future applications.

OSTI ID:
5572821
Report Number(s):
CONF-910403-; CODEN: AABUD
Journal Information:
AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 75:3; Conference: Annual meeting of the American Association of Petroleum Geologists (AAPG), Dallas, TX (United States), 7-10 Apr 1991; ISSN 0149-1423
Country of Publication:
United States
Language:
English