Abstract: Deepwater area has currently become one of the most popular domains of exploration for oil and gas for its abundant oil and gas resources. The production of deepwater oil and gas and its proportion in offshore oil and gas rises continually. For example, the production of deepwater oil and gas increased to 1.4 billion barrels in 2005 rising from less than 0.2 billion barrels in 1996. It accounted for 10% and 7% in offshore oil and gas production in 2004, which will rise to 25% and 12% in 2005. Deepwater exploration is currently the most successful and most profitable domain. However, along with the development of deepwater exploration, it will face up much more difficulties, such as smaller size of reservoir, more complicated reservoir fluid, worse marine operation, and higher requirement for techniques. To solve these problems, many advanced technologies are widely applied, including high-resolution 3D seismic technology, 4C/4D seismic technology, drilling technology of horizontal wells and extended reach wells, intellectual completion technology, various types of deepwater operating platforms, and more autonomous submarine production systems. The deep area is the extension of shallow water area in China, so it has some oil and gas geological conditions similar to the shallow water area. Deepwater area in China has favorable conditions for oil and gas accumulation and broad prospect for oil and gas exploration, which has been proved by the up-to-date discovery made in Lizhiwan3-1-1. Therefore, it is urgent to accelerate exploration and development in deepwater area and make full use of the rich oil and resources there.

Key words: deepwater oil and gas, deepwater exploration, oil and gas exploration, exploration countermeasure