Exploration progress of the Paleogene in Jiyang Depression, Bohai Bay Basin

Abstract

With increased exploration in the faulted basins of eastern China, petroleum exploration in this region has been challenged by unclear remaining petroleum resources distribution, complex reservoir and hydrocarbon enrichment patterns, and lacking of suitable exploration techniques. Aiming at resolving these problems, studies on source rocks, reservoirs, hydrocarbon accumulation and geophysical prospection were carried out by laboratory analysis, reservoir anatomy, and seismic analysis. A highly-efficient hydrocarbon generation/expulsion model of source rocks in saline environment was established, which aided in the discovery of a new set of source rocks in the Jiyang Depression. This study also reveals the formation process of high-quality reservoir by alternating acid and alkaline fluids during deposition and diagenesis, and pattern of secondary pores development in deep clastic rocks. Through the fine anatomy of the oil reservoirs, an orderly distribution pattern of the oil reservoirs is established, and the potential exploration targets in the undrilled area are identified. In addition, single-point high-density seismic acquisition and high-resolution imaging technologies are developed, enabling fine and efficient exploration in areas with high exploration maturity. The research result plays a leading and demonstrative role in the fine and efficient exploration of faulted basins in eastern China.

Keywords

• Hydrocarbon generation/expulsion model
• Saline environment
• Acid and alkaline fluids
• Hydrocarbon accumulation model
• Faulted basin