High-resolution 3d Seismic Technology Has Been Developed And Old Reservoir Description - The Daqing Portuguese South Oil Field, For Example,

This paper lakes the Daqing Punan oilfield as an example and elaborates how to re-describe an oil reservoir by using new seismic data combined with wells log and reservoir production information as well as relevance technical methods and rationale.Puna oilfield located at the southern part of Daqing placanticline, including 11 blocks, main paying zone Pu I formation of Yaojia in Cretaceous, the average net pay 3.5 meter, the single sand body length less 600 meter, the average air permeability 150 X 10 3 um2 , the average porosity 23.5%. It was discovered in 1960, development in 1984, injecting water in 1985. There were 439 wells in the early development scheme in 1983. The wel1 pattern is square, and well space is 300 meter. There were 676 wel Is in the oil field, 524 producer and 152 injecting wel Is, water cut was 47.32%, the annual production was 40x104t, and 17% oil reserve was produced, when the reserve was recalculated in 1993. The new high-resoJut ion, full cover area 295 kmJ, seismic data was surveyed and interpreted in 2001. The new information was useful for the reservoir re-describing and improving the development efficiency.The describing process, method and technologies are stated in this paper, including some smal 1 traps who are less 1. 0 km2 less 5. 0m in closed area and closure respectively being characterized by using coherent body data with accurate marking of reflecting layers. The small faults that the fault throw is less 5.0m and elongation less 50m,was characterized by using the magnified sections. The reason of casing collapsed and the confl ict between the reservoir describing and the production information can be understood easily after the smaller faults were interpreted. The indicating accuracy of sand body thickness was over 70% after lithological inversion of wells controlled by using the Geology Driven Integration and the EPS software. It is significant to evaluate new discovery traps if there are potential for development by analyzing the dry holes and the history changing of the tectonic layers and sedimentation. As more and more characteristics of the reservoir, including size and type of the reservoir, have been recognized by using the new information and technologies, over 200 extended wells were drilled and Original Oil In Place increased over 500X104t. This successful case can be referred to improve and adjust the developing effect for some similar oilfields...