Although there is no assumption of pore geometry in derivation of Gassmann’s equation, the pore geometry is in close relation with hygroscopic water content and pore fluid communication between the micropores and the macropores. The hygroscopic water content in common reservoir rocks is small, and its effect on elastic properties is ignored in the Gassmann theory. However, the volume of hygrosc...

In this study, the levels of the cysteine proteinase--cathepsin B were measured in diseased synovial fluids using a steady state fluorometric assay. Cathepsin B-like activity was shown to be present in all the samples analysed, with the rheumatoid arthritic synovial fluids possessing significantly higher concentrations (mean value ca. 416 mg/l) than the osteoarthritic fluids (mean value ca. 142...

In the middle of the 1980s, the so-called Hot Dry Rock (HDR) projects were under consideration, aiming at exploiting the heat stored in deep rocks by circulating heat-bearing fluids in closed loops through fracture networks artificially created in the rock by hydraulic fracturation. The typical geological targets of such projects were hot, and therefore necessarily deep crystalline massifs, whi...

Hydraulic fracturing is a key technology for shale gas production. Activating the natural fracture (NF) system in reservoirs and forming complex network can greatly improve effect of fracturing. The mainly influenced by geological factors operational parameters reservoir. Effectively reforming reservoir under unfavourable conditions maximizing activation NFs substantially increase its reformed ...

Conventionally, high-pressure water-based fluids have been injected for hydraulic stimulation of unconventional petroleum resources such as tight gas reservoirs. Apart from improving productivity, frac-fluids caused environmental and technical issues. As a result, much the interest has shifted towards alternative frac-fluids. In this regard, n-heptane, an frac-fluid, is proposed. It necessitate...

In this paper, we illustrate that the modern trends for viscosity prediction are moving away from empirically based methods to those that make use of a sound theoretical framework and are validated against primary experimental data. The Vesovic-Wakeham (VW) method is in the forefront of these developments. It is founded on the kinetic theory of hard-sphere fluids that is appropriately modified ...

Vapor-dominated geothermal systems, including The Geysers and Larderello, have experienced significant increases in noncondensible gas during their productive histories. A depletion model has been developed to explain these increases. In the model, the low permeability of the reservoir rock matrix initially retards the flow of vapor through the matrix to fractures due to the plugging effect of ...

The measurement of the minimum miscibility pressure (MMP) is one of the most important steps in the project design of miscible gas injection for which several experimental and modeling methods have been proposed. On the other hand, the standard procedure for compositional studies of miscible gas injection process is the regression of EOS to the conventional PVT tests. Moreover, this procedure d...

A reservoir-scale numerical conceptual model was established according to the actual geological characteristics of a carbonate fractured-vuggy reservoir. Considering difference in density and viscosity fluids under reservoir conditions, CFD (computational fluid dynamic) porous medium applied simulate process nitrogen displacement after water flooding. The effects gas injection rate, mode, injec...

Seismic data and nuclear magnetic resonance (NMR) are two of the highly trustable kinds information in hydrocarbon reservoir engineering. Reservoir fluids influence elastic wave velocity also determine NMR response reservoir. The current study investigates different pore types, i.e., micro, meso, macropores’ contribution to using laboratory experiments on coal core samples under fluid saturatio...