Study on Logging Evaluation Technology Used on M Block

In order to fine evaluation of high temperature and high pressure gas reservoirs in the western South China Sea, logging interpretation technology used in reservoir parameter study and identification of fluid properties are facing challenges. On the basis of the analyzing results on the core particle size, the analysis on the relationship of lithology, permeability and resistivity, the reservoirs are classified as three kinds, including high resistance and high permeability, low resistance and low permeability and low resistance and extremely low permeability. Through rock electricity experiment, mercury injection experiment and water analysis laboratory re-sults, three types of reservoir logging evaluation parameters have been established, which provided a solid basis for precise quantita-tive calculation of gas saturation. Fluid property identification techniques are mainly chart recognition method, inversion of resistivity and magnetic productivity evaluation. Crossplot for rapid identification is the effective method for on site logging interpretation. By inversion technique, the influence of invasion can be eliminated. High resistance and high permeability reservoirs forecasted by NML can get high productivity, but low resistance and low permeability reservoirs productivity are only class IV-V reservoir, which are ac-corded with the production testing results. Study of reservoir parameters is the foundation and guarantee for obtaining good logging interpretation in block M. With a variety of fluid property identification method, 13 exploratory wells have been evaluated, of which high production has been obtained in 4 wells. This evaluation method for high temperature and high pressure reservoirs has good ap-plication prospects in the western South China Sea.