Potential for horizontal-well technology in the US

Application of horizontal wells has increased tremendously and had signific ant and positive results in the: U.S. over the past decade. The pace of hor izontal drilling for oil has remained high since 1990 (approximately 600 to 1,000 wells/yr). Most of these wells have been drilled in three formations : the Austin chalk in Texas (79%), the Bakken shale in North Dakota (5%), a nd the Niobrara in Colorado and Wyoming (2%). Wells drilled in other format ions constitute approximately 14%. The Dept. of Energy Natl. Petroleum Tech nology Office (DOE/NPTO), working closely with industry developed a unique analytical system (including models and database) to assess the potential f or wider application of this technology to the balance of remaining U.S. oi l resources across a variety of formations. The findings of the DOE effort are the primary scope of this paper.