We present a contribution on the risk of hydraulic fracturing in CO2 geological storage using an analytical model of hydraulic fracturing in weak formations. The work is based on a MohrCoulomb dislocation model that is extended to account for material with fracture toughness. The complete slip process that is distributed around the crack tip is replaced by superdislocations that are placed in t...

1.0 Introduction Hydraulic fracturing, the process of initiation and propagation of a crack by pumping fluid at relatively high flow rates and pressures, is one of several techniques for creating cracks in rock. Fractures in the earth's crust are desired for a variety of reasons, including enhanced oil and gas recovery, re-injection of drilling or other environmentally sensitive wastes, measure...

The petroleum industry’s use of horizontal drilling and hydraulic fracturing technologies has changed organic-rich mudstones, like the Devonian Marcellus Formation, from conventional hydrocarbon sources and seals to unconventional ‘shale gas’ reservoirs. Organic-richness and formation brittleness are two principal components of reservoir quality assessment, as the former is indicative of the am...

The formation of dense spacing fracture network is crucial to the hydraulic fracturing treatment of unconventional reservoir. However, one difficulty for fracturing treatment is the lack of clear understanding on the nature of fracture complexity created during the treatment. In this paper, fracture propagation is numerically investigated to find the conditions needed for the stable propagation...

This study outlines a new method for disposing of hazardous (e.g., nuclear) waste. The technique is called Abyssal Sequestration, and it involves placing the waste at extreme depths in Earth’s crust where it could achieve the geologically long period of isolation. Abyssal Sequestration involves storing the waste in hydraulic fractures driven by gravity, a process we term as gravity fracturing. ...

Hydraulic fracturing is an important method of reservoir stimulation in the exploitation of geothermal resources, and conventional and unconventional oil and gas resources. In this article, hydraulic fracturing experiments with shale, sandstone cores (from southern Sichuan Basin), and granite cores (from Inner Mongolia) were conducted to investigate the different hydraulic fracture extension pa...

The selection of appropriate wells for hydraulic fracturing is one of the most important decisions faced by oilfield engineers. It has significant implications for the future development of an oilfield in terms of its productivity and economics. In this study, we developed a fuzzy model for well selection that combines the major objective criteria with the subjective judgments of decision maker...

Methods: A cohesive fracture model is adopted together with a discrete crack and without predetermined fracture path. The fracture is filled with interface elements which in the 2D case are quadrangular and triangular elements and in the 3D case are either tetrahedral or wedge elements. The Rankine criterion is used for fracture nucleation and advancement. In a 2D setting the fracture follows d...

Oilfield Review Autumn 2011: 23, no. 3. Copyright © 2011 Schlumberger. ClearFRAC and HiWAY are marks of Schlumberger. In 1947, Stanolind Oil & Gas performed the first experimental hydraulic fracturing treatment in the Hugoton field in southwestern Kansas, USA. Since then, E&P companies have employed this reservoir stimulation technique extensively to enhance or prolong well productivity. Indeed...