Tephrostratigraphical interpretation of historical eruptions proved by historic sites and historical sources and reconstruction of paleoenvironment

在这项研究中，我们进行了钻探调查，以调查日本不同考古遗址和历史文献(或资料)所证实的历史喷发的化石地层学，并重建古环境。就伊豆群岛的火山而言，根据矿物分析、折射率测量和元素分析(使用X射线荧光光谱仪)的结果，已经证实来自新岛、宫山、小岛和田州的火山产物分布在关头南部和东海地区。在九州中北部，我们对九州山周围地区进行了实地考察，以了解特弗拉的地层并确定其时代。在九州南部，我们对现分布在鹿儿岛湾北部Kokubu低地周围的樱岛和Kikai火山口的Tephra进行了识别和对比，以重建低地的古环境。这项研究确实有助于更好地了解火焰山与日本各地考古遗址或文物之间的地层关系，也促进了对古代文献中记录的历史喷发的澄清。除了在一些科学期刊上发表论文外，还在几个相关的学术会议上以口头陈述或海报会议的形式展示了本研究的结果。

In this study, we conducted the drilling survey in order to investigate the tephrostratigraphy of historical eruptions proved by different archaeological sites and historical documents (or sources) in Japan and to reconstruct the paleoenvironment. In the case of volcanoes in the Izu Islands, it has been confirmed that the volcanic products from Niijima, Miyatsukayama, Kozushima and Tenjosan are distributed in south Kantou and Tokai area, based on the result of mineral analysis, refractive index measurement and elemental analysis of tephra (using X-ray Fluorescence Spectrometer). In the central to northern part of Kyusyu, we conducted the field survey on the area around Kujusan in order to understand the stratigraphy of tephra and to determine the age. In the southern part of Kyusyu, we identified and correlated the tephra from both Sakurajima and Kikai caldera, which is now distributed around Kokubu lowland in the north of Kagoshima bay, in order to reconstruct the paleoenvironment of the lowland. This study really contributed to better understanding of stratigraphic relationship between the tephra and the archaeological sites or artifacts throughout Japan and also advanced the clarification of historical eruptions recorded in the ancient documents. The result of this study was presented by oral presentation or poster session in several related academic conferences in addition to the publication of paper in some scientific journals.