摘要
南海北部大陆架发育的珠江口盆地、莺歌海盆地、北部湾盆地属大陆边缘的被动盆地.盆地的演化经历了断陷、拗陷和整体沉降三个发育阶段,早第三纪为断陷充填的陆相沉积;晚第三纪为拗陷的封闭海至广海的海相沉积.主要生油层为下第三系陆相地层,储集层除下第三系地层外,上第三系海相碳酸盐岩、生物礁体和生物滩以及三角洲前缘砂体.
A series of Mesozoic and Cenozoic sedimentary basins have developed in the north part of the Continental shelf of the South China Sea, mainly located in the Zhujiang River mouth basin, the Yinggehai Sea basin and the Beibu Gulf basin, with a total area of 33xl04km2. These basins belong to passive basins of continental margin, closely related to the formation of the South China Sea. The South China Sea has at least experienced three stages of rift-ing and two stages of sea floor spreadings since late Cretaceous. The first stage of rifting from late Cretaceous to Peleocene produc NE rifting system; in the seconed and third stages, from late Eocone to Oligoce and in middle-late Miocene respectively, NW riftiag system was fornted. All the basins in the north part of the South China Sea developed from fault-depression, through dnwarping to whole subsidence. The Depocentres of basins migrated from continental side to sea gradually. The Palaeogene sediments are mainly of ter-restrial facies, consisting of alluviel accumulational, fluvial, marsh and lacustr-ine facies in order. Neogene is mainly marine, made up of semi-closed sea and open sea materials. In early, Miocene, organic reef started growing on some elevated nrassives. Thus carbonate reservoir form. In middle Miocene, a thick sequence of fluvial dta developed, and from late Miocene to Quaternary mul-ticyclic turbidites appeared in the marine sediments. Tertiary is over 10000m thick.
From early 1960's to 1988, over 15 x 104km2 of seismic profiles, near 105km of gravitational surveys, around 105km of magnetic surveys and 118 dr-illing wells (including wildcats, exploration well and production well) have been completed for oil and gas exploration. Survey and exploration done in the joint adventure with foreign companies have covered an area of 60,313km2, 38 companies from many countries have been engaged in the cooperation. Wet 10-3 field in the Beibu Gulf basin was officially put into operation in 1986. Other oil-fields, such as Wei 11-4 and Wei 6-1 oilfields, Ya 13-1 gasfield in the Yinggehai Sea basin, and Huizhou 21-1, Xijiang 24-3, Lufeng 13-1, Lufeng 22 -l and Liuhua 11-1 oilfields in the Zhujiangkou basin are ready for operation. With the expanding and deepening of explorations, the discoveries of new oil-gas fields suggest that oil and gas in the area are of timistic prospects.
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
1989年第3期63-72,共10页
Marine Geology & Quaternary Geology
