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Zibei oilfield is located in the secondary structural units on the North Shanxi Slope in the eastern of Ordos Basin, this oilfield is about 25×104km~2. The main oil-bearing reservoir contains the Triassic Yanchang Formation Chang 6 reservoir. Lithologic traps of reservoir mainly development on Chang 6 reservoir, development of sand body, mainly the-fine-grained feldspathic sandstone, physical is poor, it mainly based of low porosity and low permeability, complex of pore structure and heterogeneity of property led to the complexed logging response and logging results, these problems makes difficulties in the research about logging parameters of porosity, permeability and saturation. Therefore,the paper applies logging measures to evaluate reservoir correctly and constitutes a suit of logging evaluation standard and interpretation method which is suitable for targeted reservoir, in order to provide evidence for sustainable development of oilfleld.This paper started the research from basic geological conditions, with the core observation, cast thin section, scanning electron microscopy, mercury injection analysis study of a variety of experiments and reservoir technology. According to the foundation of research about these basic geological features etc for Chang6 oil layer in this area, and then the Chang6 reservoir is divided into four subgroups of 6~1, 6~2, 6~3 and 6~4, mainly sedimentary facies of Chang6 reservoir is deltaic deposit obtained by analyzing, the type of sedimentary micro-facies is upperwater distributary channel, and its lateral margin, inter-channel depressions, the upperwater distributary channel sand body is the main reservoir of the chang 6 reservoir. On this basis, the paper makes the systemic analysis of lithology, physical properties and oil characteristics of the log response for the key wells, do a detailed study to the oiliness, characters of lithology, physical properties and electricity of the reservoir, and made the logging evaluation of 4-property relationship of the reservoir, established the logging interpretation model of reservoir parameters. Interpretation is accuracy and accord with request plate. Application of the above achievements to the well which is beyond the key well, the result is very well. The results matched the core analysis results well. The achievements can provide more accurate theory for the logging interpretation and reservoir evaluation in this region.
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