Refined Reservoir Characterization And Field Development Planning For Lianhua Formation Of Gao-18 Block

Lianhua formation of Gao-18 block, located in the western part of Liaohe Basin, is an oil layer with significant production potential. Due to the low degree of development, the geological structure and formation characterization are not full recognized, which slows down the overall developing of the reservoir.In order to reveal the key parameters, i.e. structural and formation characterizations in the field, we employed new methods and technologies such as continental sedimentary basin sedimentology, sequence stratigraphy, and 3-Dimensional seismic data interpretation to research the block in details. Results show that, Gao-18 block is a complicated anticline structure by normal fault in general, where the major North-east fault controls the overall structure in the block. A series of minor faults in North-west and near East-west directions also divide the block to several sub-blocks. From depositional point of view, the major sedimentary facies is subaqueous fan,the depositional process controls the formation distribution and properties, and further impacts the accumulation of oil and gas in the area. The investigated region in this study is near the gravity current channel, and the provenance mainly comes from the northeast. The structure controls sedimentary and oil- gas accumulation, while the combination of structure and sand body make an important condition for high rate production. Based on a comprehensive evaluation of this formation including core analysis, production monitoring etc., we conclude that the remaining oil in this reservoir is mainly distributed vertically in a positive rhythm. Thus, we determined the plan as “water flooding the main part while steam flooding with fracturing in the East” to improve oil production. New production wells show good result of this development plan.