Abstract: By physical modeling and numerical simulation, the characters of horizontal fracturing-assisted steam flooding technology and oil incremental mechanism is summarized, that is, using horizontal fracture to control the steam overlaying rate and delay the steam breakthrough time can be effectively enhance the vertical sweep efficiency.According to characteristics of the reservoir, some new technologies and methods have been successfully applied in the pilot test, such as reasonable optimization of steam injection parameters, dual-fracture technology, dense perforation technology and steam fracturing technology.These critical technologies and methods allow the production rate, the cumulative oil-steam ratio and ultimate recovery factor of the shallow-thin and extra-heavy oil by steam flooding process to reach 17.4%, 0.21 and 37.7%, respectively.

Key words: Gucheng oilfield, extra-heavy oil, horizontal fracture, steam flooding, numerical simulation, physical modeling