琼东南盆地新生代孢粉组合及其古气候意义

发布时间：2018-04-20 14:44

本文选题：孢粉组合 + 古气候　；参考：《海洋地质与第四纪地质》2017年01期

【摘要】：以琼东南盆地深水区LS33井岩心为研究对象,通过对孢粉组合序列的分析,探讨渐新世以来各个地质时期的植被类型以及所反映的古气候特征。根据孢粉谱和聚类分析结果,LS33井岩心可划分为8个孢粉组合,不同组合之间孢粉面貌差异巨大。早渐新世,孢粉组合中以蕨类植物为优势组分,多见常绿植物,代表冷干的植物分子罕见,反映了暖湿性的热带亚热带气候。晚渐新世到早中新世,延续了早渐新世暖湿的特点,常绿栎、榛最为繁盛,植被和气候出现较为明显的垂直分带性。早中新世研究区气候发生了重大转折,温带落叶树和高山针叶林树的增多表明气候类型已转至凉干。早中新世至晚中新世常绿树的繁盛和红树科的发育表明气候属于暖湿型。上新世到更新世继承了晚中新世的特点,但红树林逐渐衰退,草本植物逐渐繁盛,意味着气候类型从暖湿逐渐转为凉干。
[Abstract]:Taking the core of LS33 well in the deep water area of Qiongdongnan Basin as the research object, the vegetation types and paleoclimate characteristics of each geological period since Oligocene were discussed by analyzing the sequence of sporopollen assemblages. According to the results of sporopollen spectrum and cluster analysis, the core of well YanLS33 can be divided into 8 sporopollen assemblages, and there are great differences in the appearance of sporopollen among different combinations. In the early Oligocene pteridophyte is the dominant component in the assemblage of pteridophytes. Evergreen plants are more common and the cold and dry plant molecules are rare which reflects the warm and humid tropical subtropical climate. From the late Oligocene to the early Miocene, the warm and wet characteristics of the early Oligocene were continued. The evergreen oak and hazel were the most prosperous, and the vegetation and climate had obvious vertical zonation. In the early Miocene study area, the climatic changes have taken place, and the increase of deciduous trees in temperate zone and coniferous trees in alpine areas indicates that the climatic types have shifted to cool and dry. The flourishing of evergreen trees from early Miocene to late Miocene and the development of mangrove family indicate that the climate belongs to warm and wet type. The Pliocene to Pleistocene inherited the characteristics of the late Miocene, but the mangrove gradually declined and the herbaceous plants flourished, which meant that the climate type gradually changed from warm and wet to cool and dry.
【作者单位】：中国海洋大学海洋地球科学学院;青岛海洋地质研究所;
【基金】：“十二五”国家科技重大专项——“南海北部深水区潜在富生烃凹陷评价”子课题《南海西部深水区古气候与古环境研究》(2011ZX05025-002-03)
【分类号】：Q914;P532

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