晚玉木冰期台湾海峡的沉积环境

对台湾海峡西部海域及河口平原14个钻孔剖面经孢粉、14C年龄和古地磁测定确定为晚玉木冰期的沉积层(Q₃3)样品进行了硅藻、有孔虫分析.结果表明,该时期海域的沉积层均属海相沉积,而河口平原区的沉积层则由海相和陆相地层交互组成.据此,提出了台湾海峡在晚玉木冰期属于水深在30～50m的浅海沉积环境的观点;阐述了这一与全球性气候冷暖更替所引起的海平面升降不一致现象是由于晚玉木冰期台湾海峡的地壳运动正处于间歇性下降时期,从而保持了浅海环境.

Sedimentary environment of the Taiwan Strait during Late Würm glaciation

The diatom and foraminifera analysis is made for the samples of Late Wurm sediinentary layers determined by palynology, radiocarbon dating and paleomagnetism from 14 cores in the estuarine plains and sea area of the western Taiwan Strait. The results show that the sedimentary layers at that time in the sea area are all marine sediments and those in the estuarine plain are composed of alternate marine and terrige- neous strata. Accordingly, an idea is proposed by authors that the Taiwan Strait in Late Wurm glaciation be- longs to the shallow sea sedimentary environment with a water depth of 30- 50m. Thus a phenomenon incon- sistent with the eustatic sea-level rise and fall caused by global climatic cold-warm replacement is suggested to be due to the differential crustal movement. During Late Wurm glaciation, the Taiwan Strait is subjected to the crustal intermittent falling so as to keep a shallow sea environment.