Zhujiangkou basin is located south from continental shelf of Guangdong province covered 175 thousand sq. km by 750km length and 300km width. In the phase of self-operation from 1974 to 1979, oil flow was discovered from Zhu-5 well. After 1979, international cooperation is the major direction in oil and gas exploration, but during the period from 1986 to 1997, self-operation in oil and gas exploration was enhanced. Thirteen oil and gas bearing structures and fifteen oilfields had been discovered with accumulative 370.49 million tons OOIP and 4100 million cubic meters OGIP. Ten oilfields was developed by international cooperation with oil production 2.9547 million tons in 1997, it is the No.4 oil production base in China.

Nanhai East oil and gas field
Wenchang19-1 oilfield is located on Wenchang19-1 structure of Zhusan depression, Zhujianmgkou basin, southern part of Guangdong province. Industrial flow was gained from Wenchang19-1-1 well based on seismic survey and geological evaluate on Wenchang19-1 structure. Wenchang19-1 oilfield was discovered by this oil production well.

It is expected that there will be 308 million tons OOIP in Wenchang19-1 oilfield and 107 million tons recoverable reserve.
Huizhou21-1 oilfield is located on Huizhou21-1 structure of Zhujiangkou basin, southern part of Guangdong province.

Huizhou oilfield was discovered by industrial flow gained from Huizhou21-1-1 well based on seismic survey and geological evaluate on Huizhou21-1 structure on Api.26,1985, it is the first oilfield with commercial value in 16/08 block of Huizhou depression, is also the first oilfield discovered in Zhujiangkou basin. oil-bearing area in Huizhou21-1 oilfield is 11.7 sq. km, OOIP is 20.26 million cubic meters.

Huizhou26-1 oilfield is located on the Huizhou26-1 structure of Zhujiangkou basin, southern part of Guangdong province.
Huizhou26-1 oilfield was discovered by industrial flow gained from Huizhou26-1-1 exploration well based on seismic survey and geological evaluate on Huizhou26-1 structure on Feb.27,1988. the maximum oil-bearing area in Huizhou26-1 oilfield is 11.6 sq. km , OOIP is 31.6 million tons.
it is the first oilfield with commercial value in 16/08 block of Huizhou depression, is also the first oilfield discovered in Zhujiangkou basin. oil-bearing area in Huizhou21-1 oilfield is 11.7 sq. km , OOIP is 20.26 million cubic meters.

Huizhou32-2 oilfield is located on the Huizhou32-2 structure of Zhujiangkou basin, southern part of Guangdong province.
Huizhou32-2 oilfield was discovered by industrial flow gained from Huizhou32-2-1 well based on seismic survey and geological evaluate on Huizhou32-2 structure at the end of 1990. OOIP is 9.92 cubic meters.

Huizhou32-3 oilfield is located on the Huizhou32-3 structure of Zhujiangkou basin, southern part of Guangdong province.
Huizhou32-3 oilfield was discovered by industrial flow gained from Huizhou32-3-1 well based on seismic survey and geological evaluate on Huizhou32-3 structure early 1991. OOIP is 14.75 cubic meters.

Xijiang24-3 oilfield is located on the southern part of fault belt, south-west sag of west end of Huizhou depression, Zhujiangkou basin, also locate in south of Guangdong province. southern part of Guangdong province. Xijiang24-3 oilfield was discovered in Api.,1985, and put on commercial production in Jan.,1995 with annual oil production 1.79 million tons and was one of major oilfields in Sichuan basin.

Xijiang30－2 oilfield is located on the southern part of fault belt, south-west sag of west end of Huizhou depression, Zhujiangkou basin, noth from 15/22 block, also locate in south of Guangdong province. Xijiang30－2 oilfield was discovered by industrial oil flow from Xijiang30-2-1X first exploration well on Xijiang30－2 structure on Jun.16,1988. Xijiang30-2 oilfield covered 5 sq. km oil-bearing area with 44.67 million cubic meters OOIP and 10.31 recoverable reserve. Put on production in Jul.,1996, oil production in Xijiang30－2 oilfield was 2.39 million tons in 1996 and 3.32 million tons in 1997.

Liuhua11-1 oilfield is located in the middle part of Dongsha uplift, Zhujiangkou basin, also is located in the sea area, southern part of Guangdong province. Liuhua11-1 oilfield was discovered by industrial oil flow from Liuhua11-1-1A well on the major high on Mar.16 ,1987. Liuhua11-1 oilfield was the biggest offshore oilfield at that time with proven 36.3sq.km oil-bearing area and 164.72 million cubic meters OOIP, it also is the largest oilfield with reef organic bank in China.

Lufeng22-1 oilfield is located in southern part of middle Dongsha uplift, Zhujiangkou basin, close to Lufeng depression, also locate in the sea area, southern part of Guangdong province. Lufeng22-1 oilfield was discovered by industrial flow from the second well Lufeng22-1-2 drilled in south-west of Lufeng 22－1-1 well in May,1989. Lufeng22-1 oilfield is a premium oilfield that can be developed with very high production and 27.76 million cubic meters OOIP.

Beibuwan basin is located in the sea area, northern bay of Nanhai, covered 19.8 thousand sq. km area which include southern part of Leizhou peninsula and northern part of Hainan island. At the period from 1963 to 1979,exploration was carried out by self-operation , but during the period from 1979 to 1984, international cooperation was the major, from then on, both self-operation and cooperation were carried out, major exploration region was concentrated in south-west of Wei depression. At the end of 1997, Beibuwan was became an important oil production base within west region of continental shelf, northern part of China sea with 12 oil and gas bearing structures, 5 oilfields, 83.56 million tons OOIP, 6164 million cubic meters of solution gas in place, 1171 million cubic meters OGIP and 104 thousand tons of condensate oil in place and 1.2215 million tons annual oil production.

Nanhai west oilfield
Weizhou10-3 oilfield is located on the fault nose of 10-3 structure (which was found by seismic survey in 1978), the south of Weixi depression, Beibuwan basin.
Weizhou10-3 oilfield was discovered by oil and gas flow at high speed from Weizhou10-3-1 well located on the shaft of nose structure, it is the earliest offshore oilfield operated by international cooperation, the partner is TOTAL of French. This oilfield was put into production on Aug.7 ,1986 and transferred to self-operating on May16,1992, the integral production base which was constructed in Weizhou10-3 oilfield on Aug.20,1991 formed 300 thousand tons production capacity and accumulated to about 4 million tons oil production up to now.

Weizhou11-4 oilfield is located on the south of lower uplift of Weixi depression, Beibuwan basin, it is a simple drape anticline and ,all boundaries are connected Weixi sub-basin except the south boundary is fault separated Haizhong depression. It is one of the major oilfields group with 9.3km length and 2.5km width and 17.7sq.km closed area.

Discovered in Nov.1982, Weixi oilfield was built on Sept.19,1993 by self-operating, designed oil production capacity was 600 thousand tons, and production capacity was grown to more than 800thousand tons after reconstructed. The integrated production make the annual production capacity grow to more than 900 thousand tons and accumulate production increase to about 6 million tons.

Weizhou12-1 oilfield is located in eastern part of Weixi depression, Beibuwan basin, about 35km from Weidao, it is the largest oilfield in the group of Weixi oilfields.
Weizhou12-1 structure was discovered early in 1979, when seismic interpretation about Weixi depression was carried out. Oilfield was discovered in Dec.1989 with proven and controlled 38.35 million ton OOIP and 13.42 million tons recoverable reserve and 5360 million cubic meters solution gas. This oilfield was established by self-operation on Jun.12 ,1999 by one million tons designed production capacity, accumulative oil production has grown to about 1.6 million tons up to now. integrating with Weizhou10-3, northern part of Weizhou10-3, Weizhou11-4 and eastern part of Weizhou11-4 to form the group of Weixi oilfields in Beibuwan, southern part of China.
The celebration of integral development in the group of Weixi oilfields was held on the Weizhou island of Beibuwan on Jul.28,1999. Total investment on this project was RMB3200 million Yuan. It will cost three years. Annual oil deliver capacity will be 500 thousand tons for Beihai refinery.