| Reservoir is defined as a place to accumulate oil and gas or a subject of hydrocarbon bearing pool empoldering, which is focused by oil & gas development engineers. Distribution and quality of the reservoir determine the fluid reservoir spatial distribution. Ultimately they make a direct impact on gas production and gas reservoir development. Physical property of gas pool in Shanxi-2 formation in Zizhou area has a great change, and it has more lithologic character. it is a typical low-porosity & low-permeability formation, which is controlled by structure and lithology. Based on the effective identification of the reservoir, It is useful for high efficient and reasonable development through effective liquid identification and confirming liquid distribution.Considering the geologic characteristics, based on traditional logging data and getting logging properties of sand, shale, and coal from description of rock core, this paper has scientifically and effectively identified lithology with multiple discriminant analysis and BP neural network, and analyzed the distribution of sand body after identify the sand of single well. This paper has established log interpretation modeling through fitting the logging properties and rock core analytic data, such as porosity, permeability and water saturation. At the same time, the author tries to study pay formation liquid log response and discrimination via some different methods, such as fluid acoustic impedance, multiple discriminant analysis and support vector machine, based on different production formation criterion and selects some applicable methods. At last, according to water chemistry and production data, the paper establishes the identification criterion for different water, and further points out the rich water area, the altitude of water contact, and the management of production wells where are nearby the rich water area.The results have shown that Shan-23 is the major productive formation. Multiple discriminant analysis and BP neural network are useful for the identification of the lithology. And the log interpretation modeling is effective. Multiple discriminant analysis, fluid acoustic impedance and support vector machine are the recommended practicable methods for Zi-Zhou reservoir during all the discussed methods. In addition, this paper sums up three water output mechanisms of lenticular water, tight water and fringe/basal water combined production performance data of 53 brought-in wells that are divided to raised, sustained, and descendant water/gas ratio, and global water chemical analysis data, and works out the recognition criteria of different water. In addition, the paper points that there are three rich water areas during the reach area and there is different characteristic for different water of the three rich water areas. Besides, the paper is also points that the total salinity of fringe/basal water was not different from lenticular water and tight water because of the condensed water. Calling on water saturation, this paper has discussed the relationship between production water and production gas. Considering the relationship, this paper has built the gas field modeling containing fringe/basal water, calculated the feasible well diameter, output and drawdown pressure. According to the prior study, this paper researches the liquid distribution based on gas-water section, and points that the gas reservoir does not have united gas/water surface, and the surface differed from west to east. Simultaneously, the paper points the location of no-water and potential-water. At last, the paper generalizes four gas/water distribution patterns and proposes the concept that the formation water salinity is affected by coal water.Sand body and liquid distribution of Shan-2 gas reservoir have become clearer than ever before through this research, which also provide a reliable basis for gas reservoir exploitation, prolonging water free gas recovery and stable production period of gas well, enhancing gas recovery, etc, in further research.
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