Abstract: Reservoir, Seal Rock Distribution, and Control Factors in Hydrocarbon-Bearing Rift Basins of China

Gong Zaisheng, Zhyu Weilin, Zheng Baomtog

With a large covering area and rich hydrocarbon potential, Bohai Bay basin is considered to be the most typical one among rift basins mainly developed in the eastern part of China. Taking Bohai Bay basin as an example, we discussed the distribution characteristics of reservoir and seal rock and some factors controlling the distribution.

Distribution of reservoir rock is roughly divided into the following categories: (1) fan delta or subwater delta and related sand on the faulting side of semigraben, (2) delta and related sand on the slope, (3) delta and related sand along the long axis of sags or depressions, (4) sand bar and sand related to storm on localized high of slope, and (5) turbidite sand in the depocenter. Correspondingly, regional and local seal rock distribution characteristics were discussed.

Factors controlling the distribution include (1) developing phases of the rift basin, (2) material supply and parent-rock property, (3) relationship between subsidence and deposition rate, and (4) the paleoclimate and paleolake level studied in detail.

From the above research and some oil/gas fields of Bohai Bay basin and other rift basins of China, favorable play concepts are suggested.

AAPG Search and Discovery Article #90982©1994 AAPG International Conference and Exhibition, Kuala Lumpur, Malaysia, August 21-24, 1994