The Description Of Lower-class Fault And Enhanced Oil Recovery Study In Kenli Oil Field

Kenli oil field is located in the east of Jiyang Depression-Zhanhua hollow zone, north with Gunan Depression, south with Fulin Depression, and east with Kendong Bulge. Since 1967, it has be founded four oil-bearing series including Palaeozoic, Mesozoic, Es and Ed. With the 30 years exploratory development, the composite water cut of Kenli oil field is 88.5%, the degree of reserve recovery is 24.5%. The Kenli oil field has gone into the high water cut stage, the difficulty of conventional infill and adjustment to raise the liquid has enhanced. Enhancing delicate comparison of reservoir, clarifying the distribution of secondary fault, even the lower-class fault, re-certain the structural form of intended zone, classifying fault system, clarifying structure format, finding undiscovered sub-shock-size block or microtectonics, modifying the distribution of remaining oil are important and necessary for synthesize adjustment of maturing field later stage and enhanced oil recovery in the high water cut stage.In the base of fine correlation of strata, this paper describes the fine 3D interpretation tech., seismic coherence analytic tech., multiscale edge detection tech., and the principle of multiple cycle grading comparison in the controlling of index horizon, the principle of isopachous or gradual thickness in the background of lithotope. With these tech. and principles, the reservoir bed of Kenli area is divided fine subzones, established delicate configuration of ground, and layers of 156 oil wells in this area are all redistributed.With the data of drilling, logging and production performance, tectonic form of intended zone is reconfirmed, the lower-class fault of sub-shock-size is found, the sealing characteristics feature of fault can be proved, which can guide rolling exploration & development and enhanced recovery in Kenli oil field getting further development. In 13 borefilds of Kenli oilfield, plenty lower-class faults and their group are found and corrected by the wavelet transform and multiscale edge detection technique. At the same time, using the technology of fuzzy comprehensive evaluation, the closed degree in different horizon of 25 faults in Kenli and Kendong-6 blocks is evaluated comprehensively from two sides of horizontal and vertical sealing ability, and on this foundation, the slave degree criterion of composite evaluation about fault sealing ability is established. A description method of lower-class fault in complicated block oilfield and the potential tapping tech. of high water cut are developed, which advance the controlling degree of resource, content the request of the flooding development and stimulation treatment in maturing field later stage.