Representation of gas hydrate fracture migration system by seismic

Abstract

The South China Sea is one of the four major offshore oil and gas accumulation centers in the world. Many oil and gas fields and hydrate deposits have been found on the northern slope of the South China Sea. The amount of hydrate resources is huge. Relying on high-precision seismic exploration technology, the exploration of hydrate deposits in the South China Sea has progressed greatly in recent years, but the success rate of seismic detection technology needs to be improved. Scientific drillings have proved that there are multiple solutions to find hydrate only by identifying BSR in the stable zone, while the research on hydrate accumulation system is not deep enough, especially the migration, accumulation and dispersion system. Fractures are the main systems of hydrate accumulation and mineralization in the north of the South China Sea. In order to effectively characterize the fracture system of hydrate, this paper, combined with the successful experience of oil and gas reservoir migration and accumulation system research, applied the fracture identification technology used to study fracture channels to discover the diapir gas field to the BSR area of Qiongdongnan Basin, and successfully identified the hydrate fracture transport system. Based on the results, the migration efficiency was discussed. In the study of gas hydrate accumulation systems, the seismic characterization of fractures can be used as a means to study the transport system.

Keywords

• gas hydrate
• migration system
• fracture identification technique
• diapir
• qiongdongnan basin