The Research Of The Methods Of Evaluation On The Compact And Low Osmotic Gas In Songnan

Currently, many of the oil-gas fields which are discovered and developed in our country are the continental deposits, the surplus oil-gas resources that are waiting to be discovered also mainly distribute in the continental deposit stratum, and the characteristic of the continental deposit of the reservoir has decided that the great proportion of oil-gas resources distribute in the low seepage reservoir. In recent years, in the petroleum geology reserves which has been verified in our country, the proportion of the low seepage reserves reaches as high as 60-70% above. For example, the Daqing Oil Field, the Jilin Oil Field, the Changqing Oil Field of Erdos Basin, as well as the Songorine Basin of Xinjiang area and tuha Basin, the reserves which has not been used basically are the low seepage reservoir, the trap belt which is recently discovered also mostly belong to the low seepage reservoir. So, the low seepage reservoir will be the main resource which can increase production for quite a long time from now on. Therefore, the exploration and research of the low seepage oil-gas storage has the good prospect, and has the special significance to the development of the oil industry in our country.The structure of Shiwu fault depression of the South of Songliao Basin is the fault depression that place in the background of the ridgy regions, the depth exceeds ten thousand meters, and the potential for prospecting of the gas in depth portion is huge. In order to obtain the breakthrough of in-depth oil-gas output in Songnan areas, besides the improving methods of drilling and picking, we should strengthen the research for application of distinction which the log information used for the low seepage reservoir fulling of gas, so that, we can adequately extract the gassy information in the log information. The goal stratum of this research is the low-compact seepage sandstone and conglomerate in depth portion, the research will be mainly on the stratum of Denglouku formation and Yingcheng formation, because their lithological character is compact, low porosity and low permeability, so they bring the huge difficulty to the work of logging interpretation.Therefore, this article sums up the geological feature of Denglouku formation and Yingcheng formation, the physical characteristic of rock and the log response characteristic for this area, and in this foundation, this article separately researches on the application method of the log information of full wave, the logging synthesis discernment methods of the oil-gas stratum and the electric conduction model of the compact argillaceous sandstone, at last, this article use these methods to carry on explanation for 18 wells of this area, and obtain one batch of gas stratum which demonstrate well.1. The summarization for the geological situation of the research areaShiwu fault depression has sufficient source, and the large-scale fold structure, its lithology trap and the oil-gas resources match advantageous, and it has the condition for forming the large-scale gas storage, it is the most advantageous basin of the gas probing in the southeast ridgy regions. But ,because the later period structure transformation is intense, the shallow gas storage is complex, the deposits are thick, the burying depth is big, the diagenesis of the deep reservoir is intense, the reservoir is compact, and the difficulty of the exploration is big.2. The application of the recognition for the full wave logging technology on the gas stratum in this areaFull wave logging technology has obtained widespread application on the division of the gas stratum and crack stratum, the computation for the parameter of the rock mechanics and so on. The records of the full wave contains rich related stratum information, through the theoretical calculation for analyzing the structure of the full wave, domestic and foreign operators had distinguished each kind of component waves and extracted useful information. This article has understood accurately on the foundation of the full wave and the characteristic of each component waves, and through research and experiment, according to different characteristic of the dynamic value method, the instantaneous frequency spectrum method, the long-short time window method and the correlation method, this article has completed the optimum composition of extraction methods, effectively distilled the information of each component waves, and carried on processing to the full wave information of SN127 well, and extracted gas target.3. The application of synthesis discernment method which extracts gas information in this areaThe stratum which contains gas is different from the oil layer at the response characteristic on the logging curves, and it has its particularity. In view of the fact that each logging method has certain limitation now, and the geological conditions also have regional questions and so on, this article has summarized and analysised the compositive target which has been used, in this foundation, it has improved the computation of the concrete target and the synthesis methods, extracted the gas information which each logging methods has detected by using synthesis distinction methods, and has synthesized organically them together, obtained a comprehensive gas target of the stratum.4. The research of the compact argillaceous sandstone electric modelThe gas reservoir in the mid depth of Songnan is the low mineralized water condition, it has low hole infiltrated characteristic, and its lithology has strong anisotropism. In order to satisfy the need of logging interpretation work under the geological condition of this area, simultaneously consider the versatility of the model, this article has done the research in view of the electrical conductivity of the argillaceous sandstone and the electric conduction, established three porosity electric model, and has carried on the logging interpretation experiment of the new electric model. The result indicated that three porosity electric model both considered the difference of the two kind of water conductance in the double water model, and considered the influence which the micropore water electric conduction brings the holistic conductivity of the rock.