The northeastern part of the city is high while the south western part is low topographically, with a southeastern plain tilted gradually downward to the Bohai Sea.

It is indicated that the technique of shielded temporary plugging is quite effective for reservoir protection of viscous oil fields with high permeability and low pressure in Bohai Sea.

All these results have laid a foundation for establishing a set of identification methods for the Neogene low-resistivity pays, and are of importance to field evaluation and development in Bohai sea.