 New plays, like the Trenton-Black River in Appalachia, thrive on new information and data. Doug Patchen, PTTC's Appalachian Region Director, has organized several workshops, drawing more than 600 attendees. Free flow of information and interplay among participants has favorably influenced the evolution of exploration, drilling and completion concepts. There is consensus on future R&D and technology needs and a multidisciplinary study involving several regional organizations and multiple industry partners has been proposed to DOE.
DOE's oil and gas R&D program through the National Energy Technology Laboratory often plays a role in development and demonstration of technology as they would if the above Trenton-Black River proposal materializes. Providing evidence of the impact of DOE support, Gary Walker from NETL's National Petroleum Technology Office in Tulsa shared case study examples from recent programs, primarily the Class program. As a point of interest, DOE was also involved in one way or another in the immediately following examples about through-casing resistivity logging (early R&D) and horizontal drilling in Michigan (key demonstration well).
 Through-casing resistivity logging took a long time to develop, but once commercialized by Schlumberger with its Cased Hole Formation Resistivity (CHFR) log, usage has increased rapidly in California (more than 250 CHFR jobs). In the California geological environment with alternating zones of oil and water or zones where current oil saturations might be different than original, having current resistivity data is critical. In his presentation, Bill Heiam with Schlumberger also discussed other newer technologies that were working in the California environment.
Bill Harrison and Robb Gillespie, representing the Michigan satellite of PTTC's Midwest Region, presented a timeline of Michigan horizontal activity. From the 1st horizontal well in 1982 through 1994, only 66 horizontal wells were drilled. Beginning in 1995 and at least partially fueled by a DOE-supported demonstration project, activity increased significantly and the reservoir targets/applications expanded. Activity, although fluctuating, has remained high and early 2003 data indicate that current levels are remaining very strong.
50% of Michigan horizontals have been for redevelopment in known oil and gas fields. Exploration and gas storage count for another 20% each. The Niagaran Reef is by far the most common target, representing 59% of horizontal wells. Other prominent reservoirs include the Antrim Shale and Michigan Stray Sandstone. Follow-up conversations with those attending PTTC horizontal drilling workshops (2001, 2002, 2003) indicate the presented technology insights and data resources of the Michigan Basin Core Research Laboratory have helped maintain the strong momentum.
Sada Joshi, Joshi Technologies, Inc., summarized overall experience with horizontal wells in the U.S. (SPE 82621). Through December 2002, there were about 17,300 horizontals with 43% of those being in the Austin Chalk, followed by the Red River formation in North Dakota. Overall, he outlined nine application environments. The majority of U.S. wells are in carbonate reservoirs, contrasted with international experience where use in clastic reservoirs is most common. His assessment is that the current commercial success rate for U.S. horizontals is 65%, although he did note that success rate generally improves as more wells are drilled in a given formation in a given area. Horizontal drilling costs might be 1.5 to 2.5 times higher than for vertical wells, but finding costs for many horizontal projects are 25% to 50% below costs of buying proved reserves. With higher productivity, operating costs on a $/bbl basis for horizontals can be half or less of that experienced by vertical wells.
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