the u.s. legacy and the global future unlocking the ... horizontal drilling, micro-seismic imaging,...

$: The U.S. Legacy And The Global Future Unlocking The ... horizontal drilling, micro-seismic imaging, and hydraulic fracturing applied to the Barnett Shale. ... n Wellbore stability$
(Editor’s Note: The Shale Revolution has the greatest potential to shape the global ener-gy industry since Edwin Parker drilled the first oil well in Pennsylvania in 1859. There was never any secret that shale formations held unimaginable reserves of oil and gas. Developing those resources economically and in an environmentally safe way was always the big challenge. Three entities can be largely credited with providing those answers: the U.S. Department of Energy, Gas Technology Institute and visionary Texas oilman George Mitchell, who knew that someday science would help unlock the mysteries of shale. This article attempts to explain the history of these momentous events).

eorge Mitchell, former head of Mitchell Energy and

Development Corp., is renowned for pioneering drilling and completion technologies that allowed gas to be extracted from shale formations. The

geologist and petroleum engineer, known as the father of the Barnett Shale, enabled viable pro-duction through the first successful application of horizontal drilling, micro-seismic imaging, and hydraulic fracturing applied to the Barnett Shale. His vision and passion for unconventional development changed the energy future in the United States and has the potential to signifi-cantly impact the world.

This successful extraction of gas from the Barnett Shale formation in Texas in the 1990s, considered to be the event that kicked off the U.S. shale gas revolution, relied heav-ily on hydraulic fracturing and other explo-ration and production research in unconven-tional gas funded by the U.S. Department of Energy (DOE) and Gas Technology Institute (GTI) — then known as Gas Research Institute (GRI) — and was able to dramati-cally improve production results.

The U.S. Legacy And The Global Future

Unlocking The Potential Of Unconventional GasSpecial To Pipeline & Gas Journal

“GTI played a key role in develop-ing hydraulic fracturing and microseis-mic technologies that are widely used to this day,” said Kent Perry, vice president, onshore programs, Research Partnership to Secure Energy for America (RPSEA), who

served for more than 20 years as an R&D manager at GTI.

Early research work by DOE and GTI were critical elements in unlock-ing the vast potential of America’s “new” natural gas, providing the world with a promising new energy future. Consider this: In 1990, unconventional gas accounted for approximately 10% of total production. Today, it accounts for nearly 60% of total production, with gas shales driving this growth. Gas shale already accounts for one-third of North American natural gas produc-tion, and is anticipated to reach 49% of U.S. production by 2035.

Early Unconventional Gas Research

Innovation and progress in the development of hydraulic fracturing, microseismic imaging, horizontal drilling, and other key gas recov-ery techniques stemmed from public-private research and commercialization efforts.

GGeorge Mitchell

GTI Technology Developmentsn FRACPRO model developed by GTI for

designing and predicting the behavior of hydraulic fractures, including the real-time monitoring of fracturing parameters. Available commercially from CARBO Ceramics Inc.

n FracSeisSM microseismic hydraulic fracture mapping for fracture diagnostics technique developed, and currently available as a suite of services from Pinnacle Technologies

n Diagnostic tools and technologies to exploit coal gas, shale gas, and low-permeability formations

- Enhanced seismic spectral processor - High power vertical seismic profile (VSP) mechanical seismic source - Seismic survey design software - STEP test for permeability measurement in coalbed methane - Cross-well seismic imaging tomography - Single well seismic - Azimvel software imaging - Microseismic imaging - Natural fracture mapping system - Fracturing: • Stressprofilingtechniquegiving strength of formations above and below fracture zone • Fractureheightmeasurementtechnique • Downholepressureprofilemonitoring - Coiled tubing guidelines, slim hole drilling, and underbalanced drilling manualn Through-casing resistivity density, and pressure

measurement tools for formation analysis n Cement pulsation tooln Jet assist drilling tooln Downhole pressure profile monitoringn Wellbore stabilityn Underbalanced completionsn 3-D reservoir characterizationsn Well siting In carbonatesn Cybergeologist n S. Louisiana deep gas

In the late 1970s, DOE-funded research resulted in advanced exploration and pro-duction technologies that enabled new gas supplies by increasing per-well gas recov-ery efficiencies and lowering unit devel-opment costs in eastern gas shales. In the early 1980s, DOE’s Multiwell Experiment (MWX) developed technology to enable economic production from low-permeabil-ity lenticular gas sands of the western U.S.

Also in the early 1980s, GTI launched a new collaborative research model that brought together a world-class team of experts from industry and academia. Together, the DOE/GTI R&D programs became a catalyst for experimentation and new technology development.

“GTI continued the early theoretical work done by DOE, took it into the field, tested it, and perfected it,” said Vello Kuuskraa, president,

GTI Unconventional Gas Initiatives Timeline

GTI Technology Developments

FRACPRO model developed by GTI for designing and predicting the behavior of hydraulic fractures, including the real‐time monitoring of fracturing parameters. Available commercially from CARBO Ceramics Inc.

FracSeisSM microseismic hydraulic fracture mapping for fracture diagnostics technique developed, and currently available as a suite of services from Pinnacle Technologies

Diagnostic tools and technologies to exploit coal gas, shale gas, and low‐permeability formations

o Enhanced seismic spectral processor

o High power vertical seismic profile (VSP) mechanical seismic source

o Seismic survey design software

o STEP test for permeability measurement in coalbed methane

o Cross‐well seismic imaging tomography

o Single well seismic

o Azimvel software imaging

o Microseismic imaging

o Natural fracture mapping system

o Fracturing: – Stress profiling technique giving strength of formations above and below fracture zone

– Fracture height measurement technique

– Downhole pressure profile monitoring

o Coiled tubing guidelines, slim hole drilling, and underbalanced drilling manual

Through‐casing resistivity density, and pressure measurement tools for formation analysis

Cement pulsation tool

Jet assist drilling tool

Downhole pressure profile monitoring

Wellbore stability

Underbalanced completions

3‐D reservoir characterizations

Well siting In carbonates

Cybergeologist

S. Louisiana deep gas

U.S. coalbed methane production greater than 1800 Bcf per

year

Research Partnership to Secure Energy for America (RPSEA)—industry‐led public/private R&D partnership—established. GTI manages RPSEA onshore unconventional gas program from 2006‐2011 and performs R&D on New Albany Shale, assesses water management and reuse technologies, and is currently characterizing the Marcellus Shale.

DOE‐funded unconventional gas research begins, focused on eastern gas shales

Devon Energy Corporation (who acquired Mitchell Energy) combines hydraulic fracturing with horizontal drilling to further improve the productivity of shale gas wells and produce gas in greater volumes than ever before thought possible.

1980 1990 2000 2010 20201970

GTI leads Water Conservation and Management Committees in the Barnett and Appalachian Shales, performs work for the New Albany Shale and Marcellus Shale Research Consortia, and develops a techno‐economic assessment of water management solutions.

DOE/GTI R&D programs, with private/public funding and involving all key stakeholders, become a catalyst for experimentation and new technology development to unlock the potential of unconventional gas. First program is coalbed methane, parallel programs on tight sands and gas shales followed on for about 15 years

GTI launches a new collaborative research model with strong industry involvement in field experiments.

First Global Unconventional Gas (GUG) Conference hosted by GTI in Amsterdam shares lessons learned from the U.S. unconventional gas revolution with the rest of the world. Summit held again in Beijing in 2011 and 2012.

RPSEA funding awarded to GTI to develop advanced techniques for economic hydraulic fracturing operations. GTI will hold a planning workshop for a new Hydraulic Fracturing Test Site in 2013.

Future R&D needs:

• Enhanced treatments for hydraulic fracturing effectiveness

• Data management and optimized efficiency for shale gas development

• Air quality, noise, truck traffic, solid waste generation, surface disturbance, and induced seismicity challenges

• Overall technology evaluation, field validation, tech transfer and support

GTI works with Mitchell Energy to drill the Stella Young well in the Barnett Shale—a novel well drilled at a high angle, rather than vertically, then stimulated with new technology. The well produces three times more gas than any other well up to that time.

Unconventional gas is 10% of total U.S. production

Unconventional gas is 60% of total U.S.

production; 33% of this is shale gas

Shale gas is estimated to be 50% of U.S. production in

2035

U.S. coalbed methane production

less than 50 Bcf per year

GTI hydraulic fracturing research begins, leading to “proof‐of‐concept” experiments at Hydraulic Fracture Test Site (HFTS) in the Rocky Mountains. Greater understanding about the fundamentals of hydraulic fracturing is gained, and methods for monitoring the creation of hydraulic fractures, leading to the development of microseismic imaging, are developed.






















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Built near Tulsa by Amoco in the 1980s as a proprietary test site, GTI Catoosa became part of GTI in 2000 to provide an all-in-one develop-ment and testing environment for new downhole tools and technologies.























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A “who’s who” of service companies have made

thousands of real-world new technology evaluations

at GTI Catoosa.

Advanced Resources International (ARI), the reservoir engineering contractor that worked with GTI on field experiments in coalbed meth-ane and shale gas. “They turned science into technology and technology into reserves of gas.”

Over the years, GTI partnered with indus-try, national laboratories, federal government agencies, universities, service providers, and geologic survey organizations — as well as producers that included BP Amoco, Shell, Texaco, Chevron, Mitchell, and others.

“The approach was different from previous efforts in that it had very strong industry involve-ment in the field,” said Perry. “Projects were tested and validated on industry wells, which was critical to the success of the program. We were able to piggyback our testing on million-dollar wells — something that GTI and the research programs could not afford on their own. That field laboratory testing was essential.”

This collaborative model has been proven successful in field programs that explored coalbed methane, gas shale, and tight sands, and has led to significant advances in best practices, processes, and procedures.

Contributions To Hydraulic Fracturing

GTI’s hydraulic fracturing research began as early as 1983, leading to “proof-of-concept” experiments at its Hydraulic Fracture Test Site (HFTS) in the Rocky Mountains. “All kinds of leading-edge technologies were verified in those field tests,” said Perry. “It included drill-ing wells for research purposes only, verifying hydraulic fracturing, microseismic, and much more. It laid the foundation for everything that

is happening right now.”This early field work was critical in improving

the industry’s understanding the fundamentals of hydraulic fracturing. “One major achievement of GTI was development of a model for designing and predicting the behavior of hydraulic fractures that included real-time monitoring of fracturing parameters such as rate, pressure, and viscosity,” noted Iraj Salehi, GTI Senior Institute Scientist, who was involved in GTI’s tight gas sands research from the 1980s on. “It’s a technology that the industry is still using today.”

Hydraulic fracture modeling was validated by both mini- and post-fracture measurements to establish a scientific basis for hydraulic fracturing, which until that time was more an art than a science. The work went beyond just analytical models — GTI developed diagnos-tics and ran lab experiments in the field to determine where a fracture goes (propagates), how far it goes, and what parameters control its destiny. One of GTI’s shallow coalbed methane wells was mined back, so pictures of the actual fractures were taken as the seams were exposed, providing amazing validation.

From the 1980s through the 1990s, “GTI developed methods for monitoring the creation of hydraulic fractures which led to the devel-opment of microseismic imaging of fractures,” said Salehi. “We also worked with Sandia [National Laboratories], which was also heav-ily involved in fracture imaging, to develop a downhole tool. GTI was a key contributor to advancing fracture diagnostics technology.”

A key technique, FracSeisSM microseis-mic hydraulic fracture mapping for fracture diagnostics, was developed by GTI to help

gas producers plan and conduct effective and economical hydraulic fracturing operations.

Advancing Understanding Of Unconventional Gas

In addition to developing technological advances, GTI contributed greatly to the indus-try’s understanding about unconventional gas resources and ways to optimize production. “We helped the industry characterize the resource and determine its potential,” said Perry.

Coalbed methane. As a result of its early work in the 1980s, GTI provided a fundamen-tal understanding about coalbed methane upon which others have built their technologies. It determined that, because of the way natural gas is adsorbed onto the coal and, in some cases, the presence of significant volumes of water, coalbed methane is not produced like other resources.

As a result, a new strategy was developed that took into account the mechanisms needed for dewatering, resource evaluation, determin-ing the amount of gas in place in an adsorp-tion environment, and fracturing in coal. As cost-effective alternatives to reinjection, meth-ods for environmentally acceptable discharge of the mineral-laden water often produced with coalbed methane were developed. GTI also developed guidebooks to help produc-ers optimize all aspects of coalbed methane operations.

GTI researchers led a comprehensive pro-gram to document those regions with the greatest coalbed methane potential, providing assessments of recoverable coalbed methane in six major geologic basins and comprehensive

models for two major basins in New Mexico and Alabama that Amoco and Arco (now both BP) and other producers used to evaluate drill-ing risks, design fracture treatments, and edu-cate investors. When GTI began its coalbed methane R&D in the early 1980s, production across the U.S. was less than 50 Bcf per year. It is now upwards of 1,800 Bcf per year.

Tight gas sands. GTI also contributed to the industry’s understanding about how to increase the amount of cost-competitive gas recover-able from tight gas sands. While significant amounts of potentially recoverable natural gas

exist in low-permeability sandstone forma-tions in sedimentary basins throughout the U.S., a combination of technical and economic constraints had historically been preventing the widespread commercial exploitation of these resources.

An integrated research program led by GTI focused on improved geology and resource parameter quantification, enhanced stimula-tion techniques, and improved fracture diag-nostics for determining fracture azimuth, frac-ture height, and overall fracture dimensions.

The research team designed and implement-ed open-hole data acquisition programs on a series of wells identified as the staged field experiments (SFEs) that worked to determine the most effective combination of formation evaluation (geological, petrophysical, and engi-neering), fracture diagnostics, hydraulic fractur-ing, and fracture modeling techniques to reduce the cost of producing gas from tight formations.

The SFEs were critical because of the need for field testing, interaction with produc-ers, enhanced technology dissemination, and technology development. Though they were costly, dedicated research sites in the field were essential to move technology forward — a real-world laboratory that enabled model validation and optimization of fracture dimen-sions, and included coring, MWD logging, wireline logging, open-hole stress testing. Pre-fracture, mini-fracture, and post-fracture analysis were also conducted.

Gas ShalesResearch on gas production from shale

resources has yielded significant new knowl-edge, enabling the industry to improve its understanding of the character of shale reser-voirs in U.S geologic basins.

An early effort in the Michigan geologic

basin involved field experiments in the Antrim Shale that helped the industry better under-stand fracture geometry in this complex forma-tion—eventually taking it from a little-known resource to a cost-competitive source of natural gas. The Antrim was really a combination of both coalbed methane and shale technologies — shale evaluation methods were used, but because the Antrim contained water, it required dewatering similar to coalbed methane.

By studying 2,000 wells, GTI developed methods that could double production rates. GTI also devised new ways to assess gas con-

tent in core samples in as little as one day and to use existing well logs and the new sampling method to help find gas beyond current wells.

GTI also pursued research on gas produc-tion from shale formations in Illinois and Texas. Several horizontal wells in the Barnett Shale were tested and evaluated with multiple fracture treatments, and a calibrated formation evaluation was performed with a cooperative Mitchell Energy well.

In 1991, GTI funded Mitchell Energy’s first successful horizontal well in the Barnett Shale in north central Texas, together partnering

with DOE to develop tools that would effec-tively fracture formations. GTI’s micro-seis-mic imaging data proved particularly useful throughout the 1990s when Mitchell Energy would make the final key innovations credited with “cracking the Barnett.” In 1998, Mitchell Energy reached a milestone as engineers achieved commercial shale gas extraction.

Having successfully demonstrated multi-fracture horizontal well drilling techniques in the Barnett, engineers had to develop the optimal combination of inputs — water, sand proppants, chemical lubricants, etc. — to achieve maximum gas recovery at the lowest cost possible. In 1998, Mitchell engineers applied an innovative drilling technique called “slick water fracturing” (or “light sand frack-ing”) that brought fracture job costs down to around $100,000 compared to $250,000-300,000 for MHF projects. This is widely considered a milestone that pushed shale gas into full commercial competitiveness.

“The big breakthrough was in drilling the Stella Young well with Mitchell Energy in the Barnett Shale,” Kuuskra explained. “This was a novel well drilled at a high angle, rather than ver-tically, then stimulated with modern-day technol-ogy. That well had three times greater production than anything else that had been drilled to date. It established that, if you can fracture a well and increase reservoir contact, you can significantly improve the productivity of these deep shales.”

In 2002, when Devon Energy Corp. acquired Mitchell Energy, it combined hydraulic fractur-ing with horizontal drilling to further improve the productivity of shale gas wells. “That was the ‘A-ha!’ moment that truly kicked off the production at Barnett, Marcellus and all of the other great shales that are now producing gas in greater volumes than ever before thought pos-sible,” Kuuskra continued. “GTI’s willingness to take scientific risks to see whether theories would work in a real-world setting pushed everything forward. It takes something like that to break the technology lock.”

Iraj Salehi, GTI Senior Institute Scientist, began work on GTI’s tight gas sands project in the 1980s.

Future of Unconventional GasGTI is providing new tools, data, and

thought leadership to ensure the safe, econom-ical, and responsible development of global shale gas. The Energy Policy Act of 2005 called for development of an industry-led public/private partnership for R&D in the production of unconventional natural gas and other petroleum resources. Section 999 of that Act allocated $37.5 million to RPSEA, a nonprofit consortium of premier U.S. energy research universities, industry, and indepen-dent research organizations.

GTI leveraged their expertise in managing the onshore unconventional program for RPSEA from 2006-2011 and continues to serve as a major technical performer in the program. The program focus is on developing gas shales in an environ-mentally acceptable manner, including develop-ment and deployment of technology to mitigate the impact to land, air, and water resources.

In 2011, GTI signed a $4.5 million con-tract with RPSEA for characterization of the Marcellus Shale and development of advanced well completion technologies and best prac-tices that address technical and environmental challenges for this resource. The project is focusing on identifying the optimum tech-niques for enhanced fracture stimulation and reliable reservoir assessment.

In 2012, GTI was awarded RPSEA funding to develop advanced methods and techniques for design and execution of environmentally safe and economically efficient hydraulic frac-turing operations. The two-year project will develop a real-time hydraulic fracturing control methodology through coupled analysis of geo-physical fracture diagnostic data and pumping pressure, rate, and fluid density; and verifica-tion of results by detailed production testing.

Included in this project is a planning work-shop for a new Hydraulic Fracturing Test Site which GTI is hosting in early 2013. The objectives of this collaborative test site are to develop a greater understanding of the dimen-sions and productivity of hydraulically created fractures in long horizontal wells, enhance the efficiency of each hydraulic fracture stage, reduce completion costs and minimize envi-ronmental footprint.

Water ManagementAs the country moves increasingly toward

development of unconventional resources, the importance and use of hydraulic fracturing has grown exponentially. In the U.S, thousands of wells are hydraulically fractured every year and the water used in the process has become a per-ceived environmental risk with the general public and key stakeholders.

For several decades, GTI has worked with representatives from academia, government, and industry to develop solutions for the con-ditioning of produced waters to enable envi-ronmentally sound and cost-effective manage-ment, by-product recovery, and beneficial use of produced water streams.

One key technology developed by GTI is the FTE® Process, a freeze/thaw evapora-tion process for treating produced waters. Partnering with DOE, Amoco Production Company, University of North Dakota Energy & Environmental Research Center, and the

U.S. Bureau of Reclamation, GTI developed a unique and cost-effective method for produced water treatment that capitalizes on naturally occurring temperature variations to reduce water management costs.

During the first decade of the 2000s, GTI has led Water Conservation and Management Committees in the Barnett and Appalachian shales, performed work for the New Albany Shale and Marcellus Shale Research Consortia, and assessed water management and reuse tech-nologies for RPSEA. Researchers are utilizing water-based life cycle modeling to provide timely planning and technology guidance for sustainable shale gas water and solid waste management.

In 2011, a techno-economic assessment of water management solutions was completed, a joint industry project with 22 companies. The study defined water management practices, emerging solutions, and benchmark costs; cat-egorized best-in-class options; and identified technology gaps and opportunities for cost reductions and efficiency improvements. GTI is also providing objective, third-party evalu-ations of client technologies from methods to fracture stimulate unconventional resources more efficiently to systems for treating flow-back and produced water more economically.

A portable water laboratory platform planned for development will monitor for the presence of corrosion-causing microorganisms within oil and gas production sites and miti-gate operational costs associated with biocor-rosion, gas souring, and water treatment.

Sharing ExpertiseGTI is working to share lessons learned

from the U.S. unconventional gas revolution with the rest of the world. One key interna-tional initiative is the Global Unconventional

Gas (GUG) Summit held in Beijing, China in November 2012. The event, building on the success of the 2011 meeting in Beijing and the 2010 conference in Amsterdam, focused on the exchange of ideas about the enormous potential of gas shale and the unlocking of unconventional gas resources in an environ-mentally and economically sustainable way.

Co-hosted by GTI and the China Energy Research Society, the event provided an elite meeting place for more than 220 senior-level International and Chinese energy experts, along with first-class speakers from the glob-al gas industry and governmental bodies. A series of high-level signing ceremonies and networking events took place at the Summit, including the signing of a framework coop-eration agreement for a training and learning center between SPT Energy Group and GTI.

In addition to these global meetings, GTI delivers customized workshops on best practices and technological solutions for unconventional gas development and produced water management to European producers and service companies. Expert papers and presentations are sharing the U.S. expertise and advocating for unconven-tional gas development across the nation and across the globe, in far-flung locations that include Austria, Poland, Istanbul, France, the Netherlands, and Korea.

GTI completed a study in 2012 in sup-port of the Polish operator’s association to assess industry best practices toward address-ing potential environmental impact of shale gas exploration and appraisal activities. The public report is being used by Polish industry in external communications regarding tech-nology applications and sustainable practices, both with government and communities.

New EIA Study: •6,622Tcfrecoverableshale•22,600Tcfrecoverablenaturalgas

Global shale adds 40%!What’s Ahead?As George Mitchell discovered, it takes

the collaboration of the right partners and technology-based solutions to make uncon-ventional gas resources productive. Today, the industry continues to face distinct and diverse challenges in optimizing the development of each resource in addition to the need for technology transfer and support. Shale gas has needs for ongoing R&D in the areas of data management and optimized efficiency. Though produced water management has been the most visible environmental solution needed, there are also challenges in air quali-ty, noise, truck traffic, solid waste generation, surface disturbance, and induced seismicity that need to be addressed. Hydraulic fractur-

ing effectiveness and enhanced treatments need further development to move forward successfully and technology needs to be evaluated and validated in the field to opti-mize performance.

Collaboration between producers, service companies, NGOs, policymakers, thought leaders, industry associations, universities and investors combined with the right advances in technology will be crucial for unconventional resources to reach their full potential. Third-party science — producing independent, peer-reviewed studies and similar data — will help greatly in promoting stakeholder acceptance.

As illustrated by the legacy of unconven-tional gas development in the U.S., R&D supported by private industry, federal gov-

Kent Perry served for more than 20 years as an R&D man-ager at GTI.

Reprinted with permission from Pipeline & Gas Journal, March 2013. © On the web at www.pgjonline.com.© Oildom Publishing. All Rights Reserved. Foster Printing Service: 866-879-9144, www.marketingreprints.com.

ernment, national labs, and research organi-zations has made a difference in gas shales development, and the benefits of research far outweigh the costs by orders of magni-tude. Ongoing R&D is needed to ensure that abundant, affordable, and clean unconven-tional gas can be produced in an environ-mentally and economically sustainable way. New tools, data, and thought leadership will help to ensure the safe, cost-effective, and responsible development of global resources and provide tremendous opportunities to take advantage of the many positive attri-butes of natural gas. P&Gj

Gas Technology Institute

1700 S. Mount Prospect Road

Des Plaines, Illinois 60018

847-768-0500

www.gastechnology.org

[email protected]

the u.s. legacy and the global future unlocking the ... horizontal drilling, micro-seismic imaging,...

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