Reservoir Logging Evaluation In Su-X Block Of Sulige Gas Field

The total resources of natural gas in low-permeability tight sand of our country are very rich. In China National Petroleum Corporation jurisdiction,the One-third proved Natural gas geological reserves are low-permeability tight sand gas type they Mainly located in the Ordos Basin, Tarim Basin, Sichuan Basin, Songliao Basin and so on.The Sulige gas field for the low porosity and low permeability, low-pressure, low-abundance of lithologic character gas reservoir, and it's distribution areas are very huge. The aeolotropism of the reservoir is so serious,thus made the"four characteristic"between different groups of sands and defferent small layers varies so obviously. The overlay model of effective sandbody in this gas field is very complex and so about the connectedness. Whether from home and abroad gas fields which have been found or has developed, it is the one of the most complex field and it is very difficult to develop. We cann't learn from any successful development experience. The gas field is at the initial stage of developmentcurrently,there is a lack of detailed and accurate evaluation of the logging methods. In order to ensure that the Su-X block rational, scientific and effective development in the district. Logging must be conducted to explain methods and gas identification technology.Research of low porosity and low permeability, low-pressure conditions of the deep gas reservoirs logging, interpretation and evaluation methods, to solve the Su-X block the single well reservoir classification, gas zone identification, logging detailed evaluation and ??r multi-well integrated gas reservoir description and prediction of the distribution in the block is of great significance. Through integrated core, log, test data, use the crossplot multiple regression analysis, build up the including shale content, porosity, permeability, water saturation, etc,are suitable for the deep gas filed under the low porosity and low permeability conditions logging interpretation model, and establish the criteria of the reservoir delineation, achieve accurate evaluation of the reservoir, with the rate of increase explain and explain the purpose of accuracy. On the base of above interpretation model and standards,i did some well logging interpretations in Su-X block (He8 section and Shan1 section) by using Geoframe logging software. And identified gas/water, based on stratigraphic correlation, analyzed in detail the Su-X block gas reservoir from the vertical and horizontal; at the same time drew the sandstone thickness, the effective gas thickness, porosity, permeability of the upper and the lower part of He8 section on Shihezi Box Formation and Shan1 Formation, determined the current favorable gas reservoir region of Su-X block.During the actual logging interpretation process I get a very deep understanding. The effective correction of logging environment is so essential. It can make logging curves reflect the situation in strata more realistically. Core to the right place or not will affect the porosity and permeability model establishment directly. Further more affect the credibility of the interpretation model.Although I did research for logging interpretation methods on this block and established the criteria of the reservoir delineation. However, due to the lack of dynamic data of wells and a small number of exploration wells data about lithologic character analysis in Su-X block,it is inevitable that individual phenomenon does not conform to the overall.Some ??lems appeared in the course of logging interpretation. (1) For the tight sandstone gas reservoir, the depth is so deep at the compact effection, the porosity turn small, fluid account the volume of rock was reduced, making the identification of dense gas is more difficult than conventional gas reservoir. Logging data are more likely to have multiple solutions. (2) Because of non-core gas saturation analysis of data temporary, so whether the archie empirical equation is suitable to well logging interpretation in Su-X block or not, and whether the Calculated gas saturation is correct or not has yet to be verified.