Reservoir Evaluation And Distribution Regularity Of Chang 6 Oil Reservoir In Tanjiaying Area Of Ansai Oilfiled

Based on core observation,combined with various analysis methods which are conventional porosity and permeability, casting thin sections and conventional constant-pressure mercury injection, the essay makes detail study on the Chang6 reservoir characteristics in the Tanjiaying area of Ansai Oilfield. Based on reservoir comprehensive evaluation, the essay researches on the Chang6 reservoir of oil and gas enrichment regularity to excellently select favorable area from the aspects such as tectonism, deposition and diagenesis.The tectonism of Chang6 reservoir in the Tanjiaying area of Ansai Oilfield shows that the superface structures subject of target strata is western-leaning monoclinal structure and only on the background of monoclinic develops several rows of nose uplift. The research showed that underwater distributary channel is the main forming of sand body. The main type of the sandstone is fine feldspathic sandstone, the physical property of the reservoir is the typical low porosity and super-low permeability, and the porosity and permeability are 9.0% and 0.85×10-3?m2 in average.With weak oil-wet reservoir characteristics, it has large range of water saturation changes in oil and water relative permeability intersection and oil-water two phase flow at the same time narrow range of water saturation.The results of the reservoir classification evaluation show that the Chang6 sand body is mainly for class IIIa and class IIIb reservoir which is about 83.3% of the sum of various reservoir types and a smaller proportion of non-reservoir types is 16.7%.With the oil and gas of Chang6 reservoir in the Tanjiaying area of Ansai Oilfield uneven distribution in the longitudinal and planar directions, the lithologic distribution and shelter of skeleton sand bodies control the oil and gas distribution,and superface structures has a slight control effect on the distribution of oil and gas.On the basement of regularity of hydrocarbon accumlation, the essay excellently selects favorable area in every small layers to provide scientific basis for the construction of a productivity.