Abstract:

The geological conditions of the complex fault block reservoir in the Paleogene of Jidong Oilfield, Nanpu Sag, northern Huanghua Depression, Bohai Bay Basin are complex. There are many faults, small fault blocks, the main reservoir is deeply buried, and it is shielded by the widely developed volcanic rocks. Therefore, the quality of seismic data is poor, the stratigraphic correlation and fine structural interpretation are difficult, the basin area is small, the source is close, the deposition rate is fast, and the sand body superposition relationship is complex. In order to effectively identify the distribution and connectivity of inter-well sand bodies and finely characterize the structural morphology, fine description and research on the complexity geological conditions in Jidong Oilfield have continuously carried out in recent years. Six key technologies have been gradually formed, including small layer division and fine correlation of complex fault block reservoirs, low-order fault identification, comprehensive characterization of delta reservoirs, formation and main controlling factors of dominant permeability channels in the process of water injection development, three-dimensional geological modeling of complex fault block reservoirs, and quantitative characterization and distribution of remaining oil, which are applied to five typical blocks, including two types of reservoir genesis of fan delta and braided river delta, and two types of physical properties of medium permeability and low permeability. In the development stages of medium water cut and high water cut, normal water injection development and overall fracturing water injection development are the theoretical basis for the rational development of complex fault block reservoirs in Jidong Oilfield.

Key words: fine reservoir description, reservoir genetic type, development method, complex fault block, paleogene, Jidong Oilfield