闽江河口第四纪地层划分和地质年代研究

本文系统地研究了闽江河口琅岐岛钻孔揭示的第四纪地层。根据孢粉、微古、硅藻和~(14)C测年等资料分析了沉积物形成时的气候波动、沉积相和沉积物年代,将闽江河口第四纪地层划分为上更新统上段(厚>15米)和全新统(厚49.80米)。全新统又可分为下全新统下段和上段、中全新统和上全新统。气候演化为:冷干→温暖略干→温暖湿润→炎热潮湿→温暖略干。沉积相演化为:冲积相、冲洪积相、湖沼相→冲积相、湖沼相→河口相、湖沼相→海湾相→河口相。

Quaternary Strata of the Minjiang Estuary and Their Geologic Ages

Based on the information of spore-pollen, forams, diatom analysis and radiocarbon datiog, the Quaternary strata revealed by the drilling on the Langgi island in Minjiang estuary are analysed to be divided into Upper member of Upper Pleistocene(more than 15 m in thickness) and Holocene(49.80m in thickness). The Holocene can be divided into lower member and upper member of Lower Holocene, Middle Holocene and Upper Holocene. The evolution sequenses of climate from the bottom to top layer are: cold-dry, temperate with slight cool-dry, temperate wetness, hot wetness, temperate with slight dry. The development sequensis of sedimemtary facies are: diluvial-alluvial facies and limnetic facies, alluvial facies and limnetic facies, estuarine facies and limnetic, bay facies, estuarine facies.