南海盆地新近纪浮游有孔虫带、气候、生物生产力爆炸事件和沉降速度的转换时限  

The Planktonic Foraminiferal Zone, Climate, Bioproductivity Explosion Event, and Time Limit of Change Subsidence Velocity in the South China Sea Basion During the Neogene

作　　者：林景星[1] 杨慧宁[1] 姜仕军 王绍芳 张静[4] 魏明瑞 许波 

机构地区：[1]中国地质科学院地质研究所,北京100037 [2]中海石油研究中心南海东部研究院,广州5102403 [3]北京自然博物馆,100050 [4]中国地质科学院水文地质环境地质研究所,石家庄050061

出　　处：《地质学报》2007年第3期285-294,共10页Acta Geologica Sinica

基　　金：海洋地质地球物理调查项目(编号960317)成果。

摘　　要：依据浮游有孔虫带的研究，南海北部浅海区LH-19-4-1井和南海北部陆坡区ODP1148站更新世的N22带，晚上新世的N21带和N20带，早上新世的N19-N18带，中新世的N17带至N4带，和晚渐新世的N3带（N3带=P22带）的地层相当，可以对比。如生物多样性在时间上的变化所示，南海北部浅海区，从晚渐新世的N3带末期至更新世N22带经历了五次降温事件（C1-C5）。C1,晚渐新世N3带末期（23．20～23．40Ma），可能相当于Mi-1事件；C2，早中新世早期N4带中晚期（22．50～21．80Ma），它与Mi-la事件相当，C2降温事件在陆坡区也有反应；C3，早中新世晚期N7带早中期（17．15～17．10Ma），可能相当Mi-lb事件；C4，中中新世中期N10带晚期（14．65～14．60Ma），可能与Mi-3事件相当；C5发生于早更新世N22带早期。14．60Ma是C4事件结束的时限、是本区古环境长时间尺度变化的时限，也是南海盆地在新近纪期间的沉降速度由慢速转入快速的时限。它还可能是青藏高原在中中新世中期开始由慢速隆升转入中速隆升变化的时限。本区从晚渐新世末期至更新世早期的环境为中-外浅海环境，在此期间，共有五次生物生产力爆炸事件（BEE1-BEE5）。BEE1和BEE2发生在早中新世早期N4带，23．2～21．5Ma期间；BEE3发生在早上新世N18-N19交界处，4．80Ma；BEE4发生在晚上新世晚期N21带，3．10～1．80Ma期间；BEE。发生在早更新世初期，1．60Ma。爆炸事件期间的生物生产力高出非爆炸事件期间平均生产力5～11倍，为原生油气藏提供了丰富的物源，给探寻原生油气田提供了重要的信息。Based on the study of the planktonic foraminiferal zones, the stratigraphy of the N22 zone of the Pleistocene, N21 and N20 zone of the late Pliocene, N19-N18 zone of the early Pliocene, N17 zone, N16-N15 zone, N14 zone, N13-N9 zone, N8-N7 zone, N6 zone, Ns zone, and N4 zone of the middle Miocene, and the N3 zone of the late Oligocene at the LH-19-4-1 borehole in the neritic province of the northern South China Sea and the ODP site 1148 in the continental slope region of the northern South China Sea are corresponding and can be correlative. The five cooling events（C1-C5） had occurred in the neritic province of the northern South China Sea since the end of the N3 zone of the late Oligocene to the N22 zone of the Pleistocene, they are：the C1 in the end of the N3 zone of the late Oligocene, 23.20-23.40Ma, it is considered the Mi-1 event; the C2 in the N4 zone middle-late stage, the early period of the E. Miocene, 22.50-21.80Ma,it corresponds to the Mi-la event and it responds to the C2 in the continental slope region; the C3 in the N7 zone eaarly-middle stage, the late period of the E. Miocene,17.15-17.10Ma, it is equal to the Mi-lb event probably; the C4 in the N10 zone late stage, middle period of the M. Miocene,14.65-14.60Ma, it could be regarded as the Mi-3 event; the Cs in the N22 zone early stage, E. Pleistogene. The 14.60Ma is the time limit of the C4 ending, is the time limit of the paleoenvironment changing in long time scale, and is the time limit of the alterning settlement velocity from slow to faster in the study area also. It may also be the time limit of the turning uplift speed from slow to faster of the Tibet plateau in the middle period of the M. Miocene. The environment fell into the middle-outer neritic province from the end stage of the late Oligocene to the early period of the Pleistocene in this sea area. The five bioproductivity explosion events（BEE1-BEE5）had happened during this period. The BEE1 and BEE2 took place in the N4 zone, early period of the E. Miocene, 23.2-21.5Ma. BEE3 in

关 键 词：南中国海 新近纪 浮游有孔虫带 气候 生物生产力爆炸事件 原生油气藏 沉降速度的转换时限 

分 类 号：Q911[天文地球—古生物学与地层学]