Introduction
Clay minerals are the most important rock consisting of clay mineral composition. The most common clay mineral is a layered structure silicate minerals, mainly kaolinite, halloysite, montmorillonite, water mica, glauconite, chlorite. Amorphous allophane clay minerals, sepiolite chain are configured like. Chemical composition of clay minerals to SiO 2 , Al 2 O 3 and water based, and there are differences of each mineral component, such as kaolinite containing Al 2 O 3 the highest, sepiolite high MgO, mica and water then K 2 O up. The crystal structure of clay minerals of different shape, have different physical properties, it can be identified as a basis. Clay minerals are ion adsorption properties from the surrounding medium, this aspect of the rock influence the properties of clay, on the other hand when the absorbent element useful in the formation of certain valuable deposits.
very fine particles of clay minerals in general, were less than 0.01mm fine scales. Having plasticity, and the sintering of the refractory, is an important natural raw material ceramics, refractories, cement, paper, petrochemical, paint, textile and other industries.
Cause
Clay minerals are an important factor affecting the performance of the sandstone reservoirs. Origin of clay minerals, the absolute content, composition, and crystal morphology of occurrence and so there is a certain relationship with the sandstone reservoir performance. Studies have shown that clay minerals of the sandstone reservoir performance affecting the degree of maturity of the sandstone itself relevant. When sandstone high maturity, with the increase of the absolute amount of clay minerals, which reservoir performance degradation, especially permeability reduction; sandstone but with high maturity and filling shaped kaolinite clay mineral content increased, the physical properties of relatively good. When the structure and composition of relatively low maturity of sandstone, clay minerals reservoir its physical property less affected, and the main components and structure of the rock itself concerned. The study also shows that different forms of illite effect on sandstone was different, Erie Shiyou Li for improving the sheet-like reservoir, whereas the fibrous illite and hairline will increase sandstone reservoir property becomes non-reducing or reservoir Floor.
Environmental Significance
Clay minerals may transition occurs during the deposition and burial. Its formation is closely related to the environment and in which the transformed therewith, and therefore in-depth study of variation in combination with the clay mineral content, and structural characteristics and the particle size distribution law conversion characteristics and the like, can be speculated that the type of weathering forming region and the source region, and climate evolution, help reveal the evolution of the global environment. A large number of the Institute of clay minerals reveal ancient climate evolution, it has been used to reconstruct paleoclimatic and paleoenvironmental recovery continent. Further, since the clay minerals having strong adsorption, ion-exchange and expansion, good adsorption performance of various types of pollutants in water, soil and have a certain self-cleaning effect, so the prevention of environmental pollution It has broad application prospects.