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.
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.
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.
The purpose of the complete paper is to create a performance-based reservoir characterization by use of production data (measured rates and pressures) from a selected gas-condensate region within the Eagle Ford Shale. The authors use modern time/rate (decline-curve) analysis and time/rate/pressure (model-based) analysis methods to analyze, interpret, and diagnose gas-condensate well-production data. Reservoir and completion properties are estimated; these results are then correlated with known completion variables. The time/rate and time/rate/pressure analyses are used to forecast future production and to estimate ultimate recovery. The data required for the completion of the proposed methodology include well-history files, daily-rate and flowing-pressure measurements, and laboratory pressure/volume/temperature (PVT) and fluid-analysis reports.
The first curable resin-coated proppant (RCP), which Fairmount Santrol introduced 40 years ago, has helped oil and gas operators solve costly proppant flowback problems. And the many phenolic novolac RCPs that the company has developed since then have become industry work-horse products. Their polymeric coatings are based on phenolic novolacs (phenol formaldehyde resin) crosslinked by the use of Hexamethylenetetramine (Hexa) as the curing agent. When general concerns arose recently about phenolic novolac RCPs potentially leaching chemicals during handling and downhole pumping, the company undertook to research to gain a full understanding of the subject. One of the specific objectives was to critically address environmental concerns about the potential leaching of free formaldehyde and phenol (Pangilinan et al. 2016) into fracturing fluids or inside propped fractures downhole from phenolic novolac RCPs.
The risk of production-harming inter-well interference, i.e. frac hits Fracture-height growth that leads to inter-formation production interference Drainage patterns and recovered volumes may leave only a small amount of oil for a DUC to capture. Real Fractured Rock is So Complex It’s Time for New ... Four Charts That Show DUCs Are Soaring in US Shale ... US Now Top Global Oil Producer But its Limits Are ...