Changes

Around the world, including Saudi Arabia, natural gas is being sought as a replacement for the far more valuable and expensive oil resource. The challenge is to develop and use this resource soundly, economically, safely, and effectively in our energy mix. It provides a means to an environmentally reasonable and abundant energy resource with a long production potential, thereby providing a bridge to the future until new energy sources are available at a reasonable cost and sufficient capacity to meet our industrial, social, and political needs—be they renewable or other forms of energy resources.

Around the world, including Saudi Arabia, natural gas is being sought as a replacement for the far more valuable and expensive oil resource. The challenge is to develop and use this resource soundly, economically, safely, and effectively in our energy mix. It provides a means to an environmentally reasonable and abundant energy resource with a long production potential, thereby providing a bridge to the future until new energy sources are available at a reasonable cost and sufficient capacity to meet our industrial, social, and political needs—be they renewable or other forms of energy resources.

United States independent petroleum companies, led originally by Mitchell Energy and Development Corp. (MEDC), pursued and developed these unconventional shale-gas reservoir systems mostly during the last 10 yr in principal, although Mitchell's effort began much earlier. In 1982, drilling of the MEDC 1-Slay well Barnett Shale for its shale-gas resource potential was the launch point for this revolutionary exploration and production (EampP) effort.<ref name=St2007>Steward, D. B., 2007, The Barnett Shale play: Phoenix of the Fort Worth Basin—A history: The Fort Worth Geological Society and The North Texas Geological Society, ISBN 978-0-9792841-0-6, 202 p.</ref> It was an incredibly difficult resource to exploit and was noncommercial through the 1980s and most of the 1990s. Even the first Barnett Shale [[horizontal well]], drilled in 1991, the MEDC 1-Sims, was not an economic or even technical success. Horizontal drilling is an important part of the equation that has led to the development of shale resource plays, but it is only one component in a series of interlinked controls on obtaining gas flow from shale. For example, without understanding the importance of rock mechanical properties, stress fields, and stimulation processes, horizontal drilling alone would not have caused the shale-gas resource to develop so dramatically. Good gas flow rates in the 1990s were typically 1.4 times 104 m3/day (500 mcf/day) or less for most Barnett Shale wells, all of which were verticals except for the 1-Sims well. The economics were enhanced when MEDC began using slick-water stimulation to reduce costs, with the surprising benefit of improved performance in terms of gas flow rates.<ref name=St2007 /> It was also learned that vertical wells could be restimulated, which raised production back to significant levels, commonly reaching or exceeding original gas flow rates. The use of technologies such as three-dimensional seismic and microseismic proved highly beneficial in moving the success of Barnett Shale forward.<ref name=St2007 /> For example, a key point still argued to this day is the impact of structure and faulting on production potential. Obviously, conventional wisdom would suggest these as positive risk factors, when in fact they are typically negative. It was learned that stimulation energy was thieved by the presence of structures and faults, thereby typically lowering success when present.<ref name=St2007 /> Application of microseismic surveys allowed engineers to map where the stimulation energy was being directed, thereby allowing adjustments to the stimulation program.<ref name=St2007 />

United States independent petroleum companies, led originally by Mitchell Energy and Development Corp. (MEDC), pursued and developed these unconventional shale-gas reservoir systems mostly during the last 10 yr in principal, although Mitchell's effort began much earlier. In 1982, drilling of the MEDC 1-Slay well [[Barnett Shale]] for its shale-gas resource potential was the launch point for this revolutionary exploration and production (EampP) effort.<ref name=St2007>Steward, D. B., 2007, The Barnett Shale play: Phoenix of the Fort Worth Basin—A history: The Fort Worth Geological Society and The North Texas Geological Society, ISBN 978-0-9792841-0-6, 202 p.</ref> It was an incredibly difficult resource to exploit and was noncommercial through the 1980s and most of the 1990s. Even the first Barnett Shale [[horizontal well]], drilled in 1991, the MEDC 1-Sims, was not an economic or even technical success. Horizontal drilling is an important part of the equation that has led to the development of shale resource plays, but it is only one component in a series of interlinked controls on obtaining gas flow from shale. For example, without understanding the importance of rock mechanical properties, stress fields, and stimulation processes, horizontal drilling alone would not have caused the shale-gas resource to develop so dramatically. Good gas flow rates in the 1990s were typically 1.4 times 104 m3/day (500 mcf/day) or less for most Barnett Shale wells, all of which were verticals except for the 1-Sims well. The economics were enhanced when MEDC began using slick-water stimulation to reduce costs, with the surprising benefit of improved performance in terms of gas flow rates.<ref name=St2007 /> It was also learned that vertical wells could be restimulated, which raised production back to significant levels, commonly reaching or exceeding original gas flow rates. The use of technologies such as three-dimensional seismic and microseismic proved highly beneficial in moving the success of Barnett Shale forward.<ref name=St2007 /> For example, a key point still argued to this day is the impact of structure and faulting on production potential. Obviously, conventional wisdom would suggest these as positive risk factors, when in fact they are typically negative. It was learned that stimulation energy was thieved by the presence of structures and faults, thereby typically lowering success when present.<ref name=St2007 /> Application of microseismic surveys allowed engineers to map where the stimulation energy was being directed, thereby allowing adjustments to the stimulation program.<ref name=St2007 />

Ultimately, industry's use of horizontal wells and new technologies enhanced success in the Barnett Shale, and industry began to recognize its gas resource potential. However, the Barnett Shale-gas resource system was typically viewed as a unique case that could not be reproduced elsewhere.

Ultimately, industry's use of horizontal wells and new technologies enhanced success in the Barnett Shale, and industry began to recognize its gas resource potential. However, the Barnett Shale-gas resource system was typically viewed as a unique case that could not be reproduced elsewhere.