Rocks texture

FIGURE 3.6 Point-bar geologic model showing the influence of a sequence of rock textures and structures in a reservoir consisting of a single point-bar deposit on horizontal permeability, excluding effects of diagenesis. (Modified after Ebanks, 1987.)... 

Unfortunately, these rock textures are relatively coarse compared to the size of the slabs used in classification (Duncan 1999). Thus, representativity is low, likely explaining why these image analysis results exhibit high scatter in Fig. 2. 

Metamorphic rocks are described by texture and/or composition. Slate, phyllite, schist, and gneiss are metamorphic rock textures, and each can have... 

Thompson J. B., Jr. (1987) A simple thermodynamic model for grain interfaces some insights on nucleation, rock textures, and metamorphic differentiation. In Chemical Transport in Metasomatic Processes (ed. H. C. Helgeson). Reidel, Dordrecht, pp. 169-188. 

Between Ca 50 °C and 300 °C, sandstones and mudrocks ( shales ) undergo massive chemical and textural reorganization. In this temperature interval detrital grains, and the rock textures defined by grains, are lost by reactions with pore fluids. Chemical and physical processes in late diagenesis transform sUiciclastic sediments into rocks. Predictive models of porosity evolution with depth depend upon an understanding of these processes. Because the magnitude of... 

Retention of host-rock texture in la and 2a Profile bleached or kaolinised, below zone of... 

Sibley, D.F. Gregg, J.M. (1987) Classification of dolomite rock textures. J. sediment. Petrol., 57, 967-975. 

The first step in the reclamation of a coal mine spoil is to make a quick physical and chemical study and evaluation of the spoil material to determine its possible uses. The chemical studies should include quick tests for acidity, sulfide and carbonate (Kohnke, 1950). The physical evaluation includes the determination of kind and amount of rock, texture of the soil material, slope of the spoil bank, drainage, and the location of the bank with relation to surrounding activities. Since any spoil bank consists of a heterogenous mixture of rocks and soil materials, not uniformly mixed, it is necessary to sample the bank at numerous locations in order to get a true picture of its capabilities. 

In previous studies, performance of basaltic rocks (textures, mineral associations, alteration... 

Figure 4 shows the rock texture and the presence of abundant clay minerals. 

Rock texture is the overall appearance of a rock based on the size and arrangement of its interlocking crystals. Crystal size is the most important aspect of igneous texture. Among the several texture varieties, three main classes can be identified phaneritic, aphanitic, and glassy textures. 

Metamorphic rocks Protolith (i.e., parent rock) Texture Description... 

For a theoretical desciiptimi, the natural rock as a heterogeneous system with internal structure must be idealized in order to formulate elastic rock properties in terms of volume fractimis and properties of the components (minerals and fluids), the rock texture, pressure, etc. In all cases, models are an idealization. 

The saturation exponent must be determined experimentally in core laboratories. It is controlled by the distribution of the conducting brine in the pore space, thus depending on the rock texture, wetting properties, and "saturation history" caused by capillary effects. 

As for other physical rock properties, it is important to note that there is a great variability for the individual rock types. This is attributed to the heterogeneity, the diversity in mineral content and rock texture, and fluid content. Clauser and Huenges (1995) made statistical studies for specific rock groups. For a detailed geothermal study, the investigation of local samples is necessary. 

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