闽江口第四纪地层中的孢粉、有孔虫、硅藻组合及其古地理意义

SPOROPOLLEN, FORAM AND DIATOM ASSEMBLAGES OF QUATERNARY STRATA IN THE MINJIANG RIVER ESTUARY AND ITS PALEO-GEOGRAPHICAL SIGNIFICANCE

本文通过对闽江口琅岐岛钻孔的孢粉,有孔虫及硅藻的综合分析,发现第四纪地层中有五个孢粉组合带,五个硅藻组合带与一个微体化石层。结合^(14)C测年资料与沉积物特征认为该地区第四纪地层可以划分为晚更新世晚期与全新世(早期、中期、晚期)。气候演化依次为:冷干→温暖略干→温暖湿润→炎热潮湿→温暖略干。沉积相发展顺序为:冲积相、冲洪积相→河流相、湖沼相→湖沼相、河口相→海湾相→河口相。

Based on the results of sporopollen, foram and diatom analysis, five spo-ropollen assemblages, four diatom ones and one microfauna have been found in the Quaternary strata at the Langqi Island of the Minjiang River estuary. According to the data of C14 dating and characteristics of the sediments, the Quaternary strata of the Minjiang River estuary may be divided into late Pleistocene and Holocene. The Holocene can be subdivided into early Holocene, middle Holocene and late Holocene. The evolution sequences of climate from bottom to top are: cold-dry, temperate-cool, temperate-humid, hot-humid, tem-perate-slightly dry. The development sequences of sedimentary facies are: diluvial-alluvial and limnetic, alluvial and limnetic, estuarine and limnetic, bay, and estuarine facies.