Evaluation Of Remaining Oil With Sealed Well Data In Shengli Oil Field

Shengli Oilfield has experienced the exploration, development and other stages since the 1960'. Development methods are conventional water flooding, heavy oil thermal recovery, chemical flooding oil,etc.. Now Shengli Oilfield is in the high water development stage. The distribution of remaining oil is difficult, and difficulty of continue development is very big. Sealed coring is the most visual, accurate and quantitative description method of remaining oil. Now, there are about 80 sealed coring wells in Shengli Oilfield. Evaluation of remaining oil is built based on core data, log data, well data and development data. Evaluation of the distribution law of remaining oil is done by core test under different development methods. Influencing factors of distribution of remaining oil is studied from displacement efficiency and sweep efficiency by physical simulation. The main results are as follows:(1) A set of perfect flooding evaluation system of sealed coring is built in fuzzy mathematics. Evolution model of water out behavior is built with sealed coring displacement efficiency, field core test and core observation. The quantitative test data is the main factor. At the same time, the color, oiliness and distribution of micro oil-water are considered in evaluation system. So the evaluation result is more scientific and reliable.(2) In this research, volatilization process and raising cores process are tested for correcting. Volatilization, degassing, porosity and mud Invading are corrected according to reversing process of coring in unconsolidated sand reservior. The correction result shows that loss amount caused by raising cores is the biggest. In this process, the water saturation loss 13.7%, and oil saturation loss 6.5%. And the influence caused by mud invading shoud be considered in coring of unconsolidated sand reservior. Oil and water saturation shoud be corrected for complete invading specimen and high invading specimen.(3) The distribution of remaining oil is universal and the enrichment of remaining oil is partial which is brought up from a strategic point of view by statistic 80 sealed coring wells in Shengli Oilfield. This idea provide a basis for continue development in in the high water oilfield.(4) According to characters of lithology and physical property of interbeds, the types of interbed could be divided into muddy interbed, calcareous interbed and silty mud interbed in fluvial reservior.(5) The main factors of remaining oil is studied quantitatively from the inner layer, interlayer and plane,etc..