[1] The coda of seismic waves consists of that part of the signal after the directly arriving phases. In a finite medium, or in one that is strongly heterogeneous, the coda is dominated by waves which have repeatedly sampled the medium. Small changes in a medium which may have no detectable influence on the first arrivals are amplified by this repeated sampling and may thus be detectable in the...

Underground longwall mining of coal causes large scale disturbance of the surrounding rock mass. The disturbance can increase the rock mass permeability through a reduction on the stress as well as formation of new fractures in the rock. Methane gas contained in the disturbed rock mass can migrate towards the low pressure mine workings and present an explosion hazard. This paper describes the a...

the electrical resistivity of hydrocarbon reservoir rocks is an important parameters in the calculation of water and oil saturation percent in both carbonate and sandstone reservoir rocks.in this regard, most studies have concentrated on the confining  pressure on cementation factor and electrical resistivity in sandstone reservoir rocks. in this study the effect of confining pressure on cement...

The petroleum industry requires the best materials to reverse the rock wettability to water-wet state which give significantly improved oil recovery.Nanoparticles are suggested as enhanced oil recovery potential agents to decrease viscosity and alter the wettability of reservoir towards more water-wet. This study provides new insights into CuO nanoparticles effects on wett...

Grieve oil field, discovered in 1954, is located in southeastern Wind River Basin, central Wyoming. This Lower Cretaceous, valley-fill and channelized, Muddy sandstone reservoir is a stratigraphic/structural trap with an average structural dip of 15 degrees. Multiple recovery mechanisms have contributed to produce more than 30 million barrels of premium light sweet crude, including gas expansio...

Although shale gas plays have been in the spotlight recently, natural gas in tight sandstones is actually also an important hydrocarbon resource. In many cases, tight gas sandstone resources can be developed more easily than shale gas reservoirs as the rocks generally have higher quartz content, and are more brittle and easier to complete for production. This chapter first gives an overview of ...

A key parameter for the application of polymer gels in water shut off treatment is the adsorption of polymer gel onto the rock surface. So, the adsorption properties of a nanocomposite hydrogel were discussed in this research by crosslinking of sulfonated polyacrylamide/sodium montmorillonite aqueous solutions with chromium triacetate. The X-ray diffraction patterns indicated that exfoliated ty...

Petrographic study of the Frewens sandstone, Upper Cretaceous Frontier Formation, documents reservoir-scale diagenetic heterogeneity. Iron-bearing calcite cement occurs as large concretions that generally follow bedding and are most common near the top of the sandstone. Median thickness of the concretions is 0.6 m, length 4.5 m, and width 5.7 m; median volume is 5.2 m. Concretions comprise 12% ...

Quantifying interactions and dependencies among geometric, hydraulic mechanical properties of reservoir sandstones is particular importance for the exploration utilisation geological subsurface can be assessed by synthetic comprising microstructural complexity natural rocks. In present study, three highly resolved samples Fontainebleau, Berea Bentheim are generated means a process-based approac...