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ODP1148站以及珠江口盆地沉积物均记录了渐新世末发生的重大地质构造事件,这一构造事件在时间上与南海扩张轴发生跳跃的时间十分吻合,是渐新世以来南海构造演化史上最为重大的构造事件,涉及到南海扩张、盆地类型转化、沉积物源变迁等一系列相关联的重大地质事件.伴随这一地质构造事件,南海北部沉积物成分发生剧烈改变,出现渐新世-中新世地球化学成分上的跳跃,在深海沉积中发生沉积间断及滑塌事件,并使珠江口盆地由断陷型盆地转为坳陷型盆地,白云凹陷由渐新世晚期的浅水陆架环境转为中新世以后的深水陆坡环境.可以认为,这次构造运动奠定了我国现代的地理格局,也标志着我国东部陆相盆地最佳烃源岩形成期的结束,在南海乃至东亚地区影响深远.
ODP1148 station and the sediments in the Pearl River Mouth Basin record the occurrence of major Oligocene geological events at the end of Oligocene. The tectonic event coincides with the time of leaping in the axis of expansion of the South China Sea. Since the Oligocene, the structural evolution of the South China Sea is the most Significant tectonic events related to a series of major geological events related to the expansion of the South China Sea, basin type transformation, sediment source changes, etc. With the geological tectonic event, the sediment composition in the northern South China Sea changed drastically and appeared in the Oligocene- The jump in the geochemical composition of the Pliocene, sedimentary discontinuities and slump in the deep-sea sediments, and the transformation of the Pearl River Mouth Basin from a fault-depressed basin to a depression basin. The Baiyun Sag was replaced by a shallow shelf environment in the Late Oligocene It is believed that this tectonic movement laid a modern geography pattern in our country and also marks the end of the formation period of the best source rock in the continental basin in the east of China and far-reaching influence in the South China Sea and even in East Asia .