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南日本太平洋一侧的晚第三纪海相地层的整个层系中产有丰富的浮游有孔虫,它可与世界热带直接对比。在北日本和日本海一侧,温水生物成分限于上第三系下部,冷水栖居动物在较新层位内占优势,这里可主要根据硅藻,并辅以放射虫和钙质超微浮游生物化石来进行地层对比。本文提出了利用浮游微化石最近建立的日本晚第三纪典型地层的生物地层和年代地层的对比关系。根据用浮游微生物地层学、与生物地层相联系的放射性年代测定、磁性地层学和地磁性年代表等建立综合的基准层已得到了年代框架。对比结果发现了一条较精确的底栖动物的年代层序界线。本文对晚第三纪陆架软体动物在时空上的分布作了归纳。最显著的生物事件之一是,在早中新世末期或中中新世初期(约1600万年前),几乎在整个日本列岛,旺盛地发育着热带和亚热带海相软体动物和大型有孔虫。这一气候所控制的晚第三纪中期的生物事件也见于太平洋区。因此,这一改进了的生物年代格局为日本列岛晚第三纪事件的全球性对比提供了基础。
The entire strata of the Late Tertiary marine strata on the South Pacific side of the South Japan are rich in planktonic foraminifera, which is directly comparable to the tropical world. On the northern Japan and Japan Sea sides, the warm-water biological composition is limited to the lower part of the Upper Tertiary, and cold-water habitat predominates in the newer horizons, mainly based on diatoms, supplemented by radiolarian and calcareous microplankton Fossils to stratigraphic contrast. This paper presents the contrast between biogenic strata and chronostratigraphy using the late-Tertiary typical strata recently established by planktonic microfossils in Japan. An age frame has been established based on the use of planktonic microbial stratigraphy, radiogenic dating associated with biostratigraphy, magnetic stratigraphy and geomagnetic dating to establish an integrated base level. The comparison shows that a more accurate zoobenthos boundary line. This paper summarizes the temporal and spatial distribution of Late-Tertiary shelf molluscs. One of the most striking biological events is the vigorous development of tropical and subtropical marine molluscs and large pores in the late Early Miocene or early Middle Miocene (about 16 million years ago), almost throughout the Japanese archipelago insect. Biological events controlled by this climate in the middle of the Late Triassic are also found in the Pacific Ocean. Thus, this improved bio-chronology provides the basis for a global comparison of late-Tertiary events in the Japanese archipelago.