Unified stratigraphy by means of Oxygen isotopes and microfossils for Paleozoic-Mesozoic siliceous deposits

该项目旨在通过放射虫和氧同位素地层学等微化石来统一生物地层学。该项目最重要的议程是组成一个由激光装置和氧气净化管线组成的激光微探针分析仪。分析器已在项目期限结束时完成，原因是与更新旧建筑和建造新建筑有关的两次搬迁。然而，新建立的分析仪比最初计划的更有用，因为它不仅产生氧同位素，而且还产生硅同位素。在新泻大学建立分析仪之前，利用日本地质调查局的激光显微探头分析仪测量了129航次期间从太平洋采集的深海硅质沉积物的氧同位素。初步研究结果表明，利用氧同位素和放射虫对上侏罗统-下白垩统地层进行了统一。放射虫古生物学和地层学的科学成果来自西藏南部的中国和菲律宾的巴拉望北部地块。在欧洲阿尔卑斯山的瑞士、意大利和斯洛文尼亚等地系统采集了远洋生物成因硅质岩。这些样品将在不久的将来用于氧和硅的同位素测量。

This project aims at unifying biostratigraphy by means of microfossils such as radiolarians and Oxygen isotope stratigaphy. The most important agenda for this project was to make up a laser microprobe analyzer composed of a laser unit and Oxygen purification lines. The analyzer has been completed at the end of the project term due to twice moves in connection to the renewal of an old building and the construction of a new building. However, the newly established analyzer is much more useful than originally planed because it produces not only Oxygen isotopes but also Silicon isotopes.Oxygen isotopes of deep sea siliceous deposits obtained from the Pacific during ODP Leg 129 were measured by using a laser microprobe analyzer in the Geological Survey of Japan before the analyzer in Niigata University was set up. A preliminary result indicates that Upper Jurassic to Lower Cretaceous stratigraphy by means of Oxygen isotope and radiolaria is successfully unified.Radiolarian biostratigraphic and micropaleontologic researches were carried out in the Mino and Chichibu Terranes, Southwest Japan. Scientific results on radiolarian paleontology and stratigraphy came from Southern Tibet in China and the North Palawan Block in the Philippines. Pelagic biogenic siliceous rocks have been collected systematically from Switzerland, Italy and Slovenia in the European Alps. These samples will be used for Oxygen and Silicon isotope measurements in the near future.