Log Evaluation And Method Research Of Thin Bed Reservoir

For a long period of times, the evaluation of thin-bed is always a difficult problem for exploration, for the influence of wall rock, conventional logging has difficulties to identify the thin-bed and calculate the interpretation parameter of thin bed effectively, and we may encounter many difficulties in evaluation of reservoir.So supported by well core experimentation, the paper analyzed the logging response feature and mechanism of thin bed, and point out that many factors can affect the logging response of the reservoir, the main factor which mostly influence the logging response is the thickness of thin layer, and the content of carbonite have a great influence on the response of 3-porosity logging.we make use of core experimentation, combined with logging material, firstly the paper do the lithology correction and thinckness correction for resistivity curves, and based on the content of mud that derived from the core experimentation, the paper present the thickness correction model of gamma-ray logging and self-potential logging, and choose the appropriate ways to compute the carbonate content and using the value of mixed frame in order to correct the influence from the carbonite, based on this, the paper gives a effective methods to correct the thickness influence for 3-porosity logging. Comparing the data which before the correction and after the correction, we can estimate the actual correction effection of the porosity, permeability and saturation of water, and calculate many important interpretation parameters such as saturation of bound water, mid-value of granularity and content of mud.Based on the study of four feature relationship characteristic, comprehensive utilization of many methods, mainly including the all kinds of cross-plot which can reflect the properties of matter and characteristic of liquid , in order to identify the property of liquid. Comparing the recognition result of the AC-RT cross-plot and the saturation of water-porosity cross-plot, we can found the accuracy of liquid identification have a noticeable improvement for the data after the thickness correction.Finally the paper discussed the application of new logging technologies in thin bed evaluation and identifying, and mainly elaborated the actual effection of nuclear magnetic resonance logging, high resolution array induction logging and imaging logging.the actual application indicated that the methods we used in the paper have a very good effects in geology and high percentage of interpretation that meet the truth, the methods we used can give a guidance in thin bed identify and interpretation for other oilfield, have a special significance and practical value.