China's eastern region, in which Daqing oil field is located, produces more than 80% of the nation's annual oil and gas output. However, after more than 40 years of exploration and production, the major reservoirs in the area's oil and gas fields eventually have become less productive. The reservoirs in the area are characterized by stratigraphic traps, fault blocks, and minor effective thickness (less than 10 m in general). To identify such reservoirs we have developed a series of high-resolution 3D geophysical exploration methods. This not only helped in the discovery of new reservoirs, but also increased the production of some old oil and gas fields.