Wellbore instability in oil and gas drilling is resulted from both mechanical and chemical factors. Hydration is produced in shale formation owing to the influence of the chemical property of drilling fluid. A new experimental method to measure diffusion coefficient of shale hydration is given, and the calculation method of experimental results is introduced. The diffusion coefficient of shale ...

the continuous development of global economy with decreasing in available hydrocarbon sources and increasing discovery and extraction costs due to decrease in-situ oil and gas reservoir, displays the necessity of using new techniques for the improve rate of penetration and productivity in well. nanotechnology has already contributed significantly to technological advances in the energy industri...

Although the retorted, or processed, shale represents the largest by-product from oil shale retorting operations, results from detailed studies indicate that it can be managed in an environmentally acceptable manner. Laboratory and field tests have demonstrated the following properties: using normal vehicular traffic; cementation strength to 1480 kPa, using only retorted shale and optimum water...

A big challenge in studying organic rich shale is to predict its kerogen content and maturity from indirect observations. Kerogen maturation changes shale texture; for example, it generates microcracks and fractures in the matrix. Assessment of maturity from indirect measurements can be greatly enhanced by exploiting any existing correlations between physical properties, microstructure, and ker...

This paper presents main results of a shale stability study, related to the understanding of shale/ fluid interaction mechanisms, and discusses shale strength correlation. The major shale/ fluid interaction mechanisms: Capillary, osmosis, hydraulic, swelling and pressure diffusion, and recent experimental results are discussed. Factors affecting the shale strength are discussed, and a sonic com...

Extremely low permeability due to nano-scale pores is a distinctive feature of gas transport in a shale matrix. The permeability of shale depends on pore pressure, porosity, pore throat size and gas type. The pore network model is a practical way to explain the macro flow behavior of porous media from a microscopic point of view. In this research, gas flow in a shale matrix is simulated using a...

Worldwide interest in shale plays has rapidly increased in recently years, thanks to the combination of horizontal drilling and hydraulic fracturing. Shale formations act as both the source and the reservoir for the natural gas and usually exhibit anisotropic properties at larger scale. Geological and petropysical studies found that the right combination of thickness, TOC (total organic carbon)...

fluid properties with constant improvement in efficiency have been noticeable as important criteria in drilling operation. the main drilling fluid properties highly depend on utilization of new polymers with high efficiency in drilling fluid composition. in this paper, the performance of a new polymer, called partially hydrolyzed polyacrylamide polymer (phpa), is studied which has recently ente...

Gas storage and flow behavior in the shale gas rocks are complex and hard to identify by conventional core analysis. This study integrates clustering analysis techniques from material science, petrophysics, and petrology to characterize North American shale gas samples from Utica, Haynesville, and Fayetteville shale gas plays. High pressure (up to 60,000 psi) mercury porosimetry analysis (MICP)...

Hydraulic fracture in shale reservoir presents complex network propagation, which has essential difference with traditional plane biwing fracture at forming mechanism. Based on the research results of experiments, field fracturing practice, theory analysis, and numerical simulation, the influence factors and their mechanism of hydraulic fracture extending into network in shale have been systema...