Basic Geologic Research And Development Plan In BoHai "A" Oilfield

"A"Oil Field is located in the middle of Liaoxi Sag in Liaodong Bay, and at the downthrow of Liaoxi No. 1 Fault, which is very close to Liaoxi Uplift in the west. It's a typical fault-block oil reservoir discovered in January of 2002. The main oil-bearing zones are in the lower interval of the second member of Ed, with main lithology of fine sands of lacustrine delta and some mid-fine sands in the reservoir formations, and there are a little of mid-coarse sands and very sands in partial interal. Separated by faults and effected by thick shale zones, the distribution of oil and gas of"A"Oil Field is very complex, and is controlled by the faults, consequently forming structural layered oil reservoirs with several fluid systems vertically and horizontally.with crude oil property is conventional medium oil. The proved oil-bearing area of"A"oilfield is 2.2km~2, the proved oil reserve in place of 948×10~4m~3, and the proved solution gas reserve in place of 5.49×10~8m~3.According to the distributions of oil & gas and reservoir characteristics, combined with the feasibility of offshore engineering"A"oilfields is developed by vertical wells and horizontal wells with approximate innverted nine-spot water injection pattern, And produced by utilizing the onshore facilities of SZ36-1 oilfield. with yearly production at the beginning of 25.8×104m3, production rate of 2.8% for 4 years. After 15 years of production, total oil production could be up to 256.1×10~4m~3, with recovery of 24.8% and water cut of 86%. According to engineering economic evaluation, its internal profit exceed the economic yardstick of the petroleum industry that the state stipulation.