Shale gas is defined as natural gas occurring in shale formations. It is an unconventional energy resource, which has become an increasingly important source of natural gas globally and has the potential to grow as a major energy source in the next decade. However, production of shale gas remains technically and economically challenging. Having high total organic content and falling in the gas window (302 F–392 F), shale has sufficient potential to generate huge amounts of natural gas. Generally, natural gas is stored in a shale matrix, which is highly porous but has very poor permeability.
It is strongly believed that better reservoir characterization and better modeling technique selection ought to shorten the learning curve and save money. This article reviews the state-of-the-art on fracture spacing optimization and discusses the challenges that the industry is facing to achieve an optimal cluster spacing decision. The current technology to develop unconventional resource plays is a horizontal well with multistage hydraulic fracturing treatments. Since permeability is extremely low ( 0.001 md) in unconventional resource reservoirs, multiple fractures are needed to have economic well rates, as shown in the image on top (Figure 1). Currently, the most popular completion technique is plug-and-perf, where each completion stage includes single or multiple perforation clusters and multiple fractures are initiated from perforation clusters.
Situated in central Mexico, Mexico City sits at a minimum elevation of 7,217 ft in the Valley of Mexico, a fitting location for one of North America's most important financial centers. It is truly a global city, in every sense of the term, with its rich background and the continuing diversity of its population. Human history in this area stretches back to nearly 8000 BCE, when agriculture (focusing on crops like squash) was first being implemented in the Americas. Contact with early conquerors and settlers entirely changed the Aztec, the final of these civilizations, and eventually led to the creation of a city ripe for international trade. The city itself is not part of any Mexican state, but resides in its own federal district and consists of 8.85 million people (according to a 2010 census); however, the surrounding area, formed by 16 boroughs and other municipalities in the Valley of Mexico, pushes that number to over 21 million.
I won't pretend to have planned the career I've had from the outset, so to some extent accident and luck played roles. My dad was in the energy sector--he was a field superintendent for Gulf Oil Company for 30 years--so I grew up around the industry. I went to Oklahoma State University (OSU) and got an accounting degree. After I graduated, I specialized in tax work for companies and individuals, many of whom were, not surprisingly, in the energy sector. I ended up taking a job with a highly successful man in Tulsa who helped me get to know the industry quite well.
The quality or quantity of oilfield water is often a problem: There may be inadequate quantities, excessive quantities, or it is not the right kind of water for its intended use. Using less water in oilfield operations is commendable and promotes conservation. Recovering spent fracturing water and formation water for reuse as fracturing makeup water is even better because the practice is sustainable and applaudable. The volume of spent fracturing fluid returning as flowback varies from basin to basin, from less than 15% in the Eagle Ford Shale to up to 40% in the Permian Basin and Bakken Shale. While the percentage of recovered fracturing water may not change, the overall volume recovered is on the rise (Boschee 2014).
Digital image correlation (DIC) is routinely used in modern mechanical engineering to analyze the strength of building materials. Geologists have used the technology for the same reason in the study of mines. Now, researchers from the University of Louisiana at Lafayette are making the case that DIC can also help petroleum engineers--specifically those in the business of hydraulic fracturing. The ultimate aim: an index of unconventional rock types based on a quantification of their ability to be stimulated, or what oil and gas producers simply call "fracability." DIC technology has a few variations, but this application involved the coupling of a high-speed camera with commercial change-tracking software.
The oil and gas industry is coming to terms with a cyber threat landscape that has expanded beyond data breaches and the theft of intellectual property. The latest battlefront is in the field where critical drilling and production assets are at risk of being disrupted or destroyed, thanks to their highly vulnerable control systems. The industry has experienced only a few cases of these so-called cyber-to-physical attacks but the US Department of Homeland Security predicts that by 2018 cyber attacks against oil and gas infrastructure around the world will cost almost USD 1.9 billion. One of the most dire warnings comes from the multinational risk adviser and insurance firm Willis Group, which in 2014 reported that "a major energy catastrophe, on the same scale as Piper Alpha, Phillips Pasadena, Exxon Valdez, or Deepwater Horizon,could indeed be caused by a cyber attack." The company noted in its report that insurance providers generally will not cover such events.
A real-time method is presented to predict impending stuck pipe with sufficient warning to prevent it. The new method uses automated analysis of real-time modeling coupled with real-time-data analysis. It can be applied to all well types for any well operation. The new method combines two types of analysis: (1) deviation of real-time data from real-time model predictions by use of hydraulics and torque-and-drag software, and (2) trend analysis of real-time data. The approach taken was to first study real-time data sets from wells in which stuck-pipe incidents occurred and determine the root cause of each.
Phil Martin, CEO of New Century Exploration, urged US E&P companies to leverage data and rapidly adopt digital technology in a talk at the Leaders in Industry luncheon held by the Independent Petroleum Association of America and the Texas Independent Producers and Royalty Owners Association recently in Houston. Titling his presentation "Hope is not a Strategy," Martin urged companies to move quickly to take advantage of data-driven opportunities. "If you look to the data and allow the lessons that you learn to guide your decisions, you will be golden," he said. "You've got to let the real numbers play a big role in your guidance." Continuing improvements in technology in recent years have led to "incredible" productivity gains in the industry, Martin said, citing an average 25% annual improvement in the barrels of oil produced per rig over the last 6 years.
In its report for year ended 30 June, BHP Billiton yesterday said it was planning to "only divest for value" its US onshore assets. While it considers options, the company will continue to complete well trials, acreage swaps, and look into midstream solutions to increase the value, profitability, and marketability of the assets. The company reported its second-highest free cash flow on record--$12.6 In the report, the company stated, "As part of our ongoing review of our portfolio, the Board and management have determined that our onshore US assets are non-core and options to exit these assets are being actively pursued." The sale of a portion of the Hawkville shale field located in Texas is anticipated to be completed in the September 2017 quarter.