摘要
根据D_1A段单道地震剖面反射特征发现了南海东北部晚第四纪地层不整合,并被第四系浅钻ZK3孔岩心的岩性、古生物和测年所证实。上部不整合造成中更新统顶部至上更新统上部间的缺失。该不整合主要是由于末次冰期盛冰期海平面下降形成,其次是受末次冰期前局部构造变动的影响。据测年推算,15.6 ka B.P.海平面相对现代海平面下降了146 m,当时的古海岸线位于距今海岸约170 km处。这就为南海东北部末次冰期盛冰期海平面下降幅度提供了实际证据。
According to the reflection characters of D_1A segment in the single seismic profile, we discover the late Quaternary strate unconformity in northeastern South China Seas, which is confirmed by the lithology, palseobiology and age of borehole ZK3. The upper unconformity engenders the sediment absence of top middle Pleistocene to top upper Pleistocene. It formed firstly by the sea level falling during pleniglacial of kataglacial; secondly, affected by the local tectonic variance before the kataglacial. The sea level has fallen relatively 146m to modern sea level in 15.6 ka B. P., when the paleocoast-line sited off 170 km to modern coast-line at that time, and provided the evidence of the falling of sea level during pleniglacial in northeast area of the South China Seas.
出处
《南海地质研究》
2002年第13期55-61,共7页
Gresearch of Eological South China Sea
基金
部控地勘项目:地勘项目专项资助(地发[1997]232号)
关键词
南海
晚第四纪
地层不整合
末次冰期盛冰期
海平面变化
古生物
岩性
northeastern South China Seas
late Quaternary
stratal unconformity
kataglacial and pleniglacial
sea level changes
