Decreased technological costs and increased efficiency of horizontal drilling has made obtaining natural gas from shale deposits through hydraulic fracturing a viable economic option. However, current estimates of per kWh costs to obtain natural gas through this method do not account for increased environmental risks. By incorporating damages from air and water pollution, the true cost of hydra...

Over the past decade, there has been a surge in drilling for natural gas and oil in shale rock. Natural gas and oil extraction using high-volume, slickwater hydraulic fracturing from clustered multiwell pads using long, directionally drilled laterals (known by its popular name ‘fracking’), is an unconventional extraction process that is currently the focus of controversy. The process involves t...

The development of most unconventional oil and gas resources relies upon subsurface injection of very large volumes of fluids, which can induce earthquakes by activating slip on a nearby fault. During the last 5 years, accelerated oilfield fluid injection has led to a sharp increase in the rate of earthquakes in some parts of North America. In the central United States, most induced seismicity ...

Hydraulic fracturing is used to increase the permeability of shale gas formations and involves pumping large volumes of fluids into these formations. A portion of the frac fluid remains in the formation after the fracturing process is complete, which could potentially contribute to deleterious microbially induced processes in natural gas wells. Here, we report on the geochemical and microbiolog...

By way of introduction, the general invariant integral (GI) based on the energy conservation law is presented, with mention of cosmic, gravitational, mass, elastic, thermal and electromagnetic energy of matter application to demonstrate the approach, including Coulomb's Law generalized for moving electric charges, Newton's Law generalized for coupled gravitational/cosmic field, the new Archimed...

The use of horizontal drilling and multistage hydraulic fracturing technologies has enabled the production of immense quantities of natural gas, to date principally in North America but increasingly in other countries around the world. The global availability of this resource creates both opportunities and challenges that need to be addressed in a timely and effective manner. There seems little...

Shale gas extraction involves the drilling of organic-rich, lowpermeability shale and then stimulation of hydraulic fractures that allows gas to be produced. Methane in aquifers located above the shale strata, for instance, in Pennsylvania, United States, has been attributed by some to be the result of contamination caused by the hydraulic fracturing process. The work by Osborn et al. (1) descr...

This paper presents a modeling approach for three-dimensional simulation of hydraulic fracturing of jointed rock. The base for a successful computer based simulation for productive use is the ability to calculate the fractured volume with sufficient accuracy and efficiency. Especially in cases three dimensional effects have to be taken into account, the common commercial software tools in oil a...

Hydraulic fracturing in shale gas reservoirs has usually resulted in complex fracture network. The results of micro-seismic monitoring showed that the nature and degree of fracture complexity must be clearly understood to optimize stimulation design and completion strategy. This is often called stimulated reservoir volume (SRV). In the oil & gas industry, stimulated reservoir volume has made th...

Oil and natural gas from deep shale formations are transforming the United States economy and its energy outlook. Back in 2005, the US Energy Information Administration published projections of United States natural gas supply that stressed the need to develop an import infrastructure (1): by 2025, imports would account for almost one-third of United States consumption. When we compare those fo...