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在长390cm的柱状岩芯中大致以10cm的间距采样,所取的34个孢粉样品经处理,几乎全含丰富的孢子花粉。在此基础上划分出3个孢粉组合带,自下而上为: 1.Chenopodiaceae-Artemisia带;2.Potamogeton,Sparganium,Typha-Gramineae带;3.trilete spores-Pinus带。 本文依据孢粉植物群所反映的沉积环境变迁探讨全新统与更新统的划分。 Chenopodiaceae-Artemisia带以滨岸盐生植物分子为主,反映为岸线附近的沉积环境;Potamogeton,Sparganium,Typha-Gramineae带主要分子的母体植物为静水水生与中生植物,反映湖沼沉积环境,说明当时当地离海岸线有一定的距离;trilete spores-Pinus带多见于我国东海海底现代表层沉积,指示了一种现代的海洋环境。 以上三种沉积环境反映了带1至带3期间海水的进退历史,即带2时期海退最大,带3时期海进最大,由于古气候的冷暖变化是第四纪海面升降的主要原因,因此推断带2时期气候最冷,而带3时期气候最暖,也即带2、带3间可能为更新统与全新统的界线。 根据孢粉分析所推断的全新统、更新统界线与岩芯特征、钙质超微化石以及~(14)C测年资料吻合。
Samples were taken at roughly 10 cm intervals in a cylindrical core of 390 cm in length, and 34 sporopollen samples were processed and almost all were enriched with spore pollen. On this basis, three spore-pollen assemblages were identified. The bottom-up sequences were: 1.Chenopodiaceae-Artemisia band; 2.Potamogeton, Sparganium, Typha-Gramineae band; 3.trilete spores-Pinus band. Based on the changes of sedimentary environment reflected by sporopollen assemblages, the paper discusses the division of Holocene and Pleistocene. The Chenopodiaceae-Artemisia belts are dominated by littoral plants and are reflected in the sedimentary environment near the shoreline. The parent plants of the Potamogeton, Sparganium and Typha-Gramineae belonged to the hydrostatic and mesophytes, reflecting the lacustrine sedimentary environment At that time there was a certain distance from the shoreline; the trilete spores-Pinus belt was more common in the modern surface sediments of the seabed of the East China Sea, indicating a modern marine environment. The above three depositional environments reflect the history of seawater advance and retreat during the period from Belt 1 to Belt 3, that is, the maximum of regressive sea level in Zone 2 and the maximum of marine sea level in Zone 3 since the paleoclimate is the main reason for Quaternary sea level rise and fall It is inferred that the coldest climate in zone 2 and the warmer zone in zone 3, ie zone 2 and zone 3 may be the boundaries of the Pleistocene and Holocene. According to the deduced Holocene and Pleistocene lineages from sporopollen analysis, they are consistent with core features, calcareous microfossils and ~ (14) C dating data.