福建泉州晚第四纪盆地沉积的孢粉和微体古生物及其古环境意义

摘要

The sediment sporopollen be during the late quaternary period in Quanzhou City, the arboreal pollen exceded to adape to a large range of climate and the fern spore used to worm and dank climate was less in late pleistocene. The two content were much more similar in early holocene. The fern spore increased and the arboreal polle was the second in midholocene. The fern spore occupyed absoluteness predominance and a relative decrease in the arboreal pollen late holocene. The herb pollen concentration is not high, but update with the times, the type increases. The microbody paleontology presented the foraminifer and the diatom that the variety were less and the abundance was not high in the area late pleistocene and early holocene. Foraminifera, ostracods and diatoms were widely distributed, high concentration and great variety in middle and late holocene. According to the sporopollen, microbody paleontoloty, dating data and lithofacies information of lithology strata analysis shows that the climate of the late quaternary period changed from a cold and dry climate （cool and relatively wet）→ warm and humid （moist） → warm （warm hot）. The sedimentary evironment happened twice changes of sea level rise and decline in the last stage of late pleistocene, early holocene, and late holocene. The sea level was the lowest under the present sea level 20 m-≥40 m in late pleistocene. The sea level of early and middle holocene was in rising stage up the present sea level 10m, and the peak was 7 000-4 000 a ago. Later, the sea level droped slowly, and near to the present sea level was 2000 a ago. The seawater completely withdrew from this area in 0. 3 ka ago, and the basin seals up into the Quanzhou peneplain.%福建泉州晚第四纪沉积物中孢粉，晚更新世以气候适应范围较宽的木本植物花粉占优势，适应温暖湿润气候的蕨类植物孢子较少；早全新世二者含量相当；中全新世蕨类植物孢子增多，木本植物花粉退居第二；晚全新世蕨类植物孢子占绝对优势，木本植物花粉相对减少。草本植物花粉浓度始终不高，但随着时代更新，种类增多。区内微体古生物在晚更新世和早全新世都出现种类不多、丰度不高的有孔虫和硅藻；中、晚全新世有孔虫、介形虫和硅藻分布广、浓度高、种类多。根据孢粉、微体古生物和测年资料，结合岩性岩相等地层信息分析表明，区内晚第四纪气候经历了寒冷干旱（温凉较湿）→温暖潮湿（湿润）→温暖（暖热）湿润的演变，沉积环境发生了晚更新世末期和全新世早期至晚期两次海进海退变化；海平面晚更新世最低，波动于现今海面以下20m～≥40m，早、中全新世海面处于上升阶段，其峰值在距今7000-4000a，为现今海面以上约10m，此后，海面缓慢下降，至距今约2000a接近现今海面，距今约0．3ka海水完全退出，盆地封闭成为泉州准平原。