Optimization Of Favorable Areas In Putaohua Reservoir In BP26-32 Well Block, Songliao Basin

With an area of about 26km2, BP26-32 well block of Songliao Basin is a membership of Zhaozhou oil field. And it is located in the north of Zhaozhou County, Daqing City, Heilongjiang Province. The block is currently in the early stage of development, which requires a more in-depth study of the reservoir geological features of it, such as structure, sedimentary, sand body distribution, etc. On the basis of the small layer division and correlation, the paper makes full use of geological, geophysical and test datum, and focuses on the research of structural analysis, sedimentary evaluation and reservoir prediction, combined with the results of petroleum entrapment research, optimizing the advantageous development blocks. The main understanding and achievements are as follows.(1) Take the advantage of the 3D seismic interpretation and coherence cube technology for the structure interpretation, the paper finds that, the top of the Putaohua oil layer grows soft and gentle with a distribution from 1270 m to 1320 m below sea-level. In addition, there are lots of micro-amplitude structures distributed in the area, such as the micro-amplitude anticline, the micro-amplitude fault nose, and the micro-amplitude fault block.(2) Making full use of the logging data, the paper carried out the analysis of single well facies, profile facies and plane facies of the well block. The material source comes from the north and the west in two directions. The growth of the estuary bar has limitation, however the sand sheet grows in large continuous tablets.(3) In this paper, seismic attribute analysis and seismic inversion technology was applied to the sand body prediction. The sand body distribution is mainly affected by the sedimentation factors. With a banding distribution, the thick layer of sand body suits to the material source. The maximum thickness of sand body is about 13 m at the river Interchange. However, the minimum thickness of sand body is below 5m at the north and the south-west of the well block.(4) According to the reservoir type and the reservoir forming characteristics, referencing the test data of the completed wells, the paper selected three Ⅰ class and three Ⅱ class favorable areas in the well block. Three evaluation wells were proposal to deploy.