Japan Geoscience Union Meeting 2021

Presentation information

[J] Poster

O (Public ) » Public

[O-02] Natural disasters and people -Listen to the voice of the Earth on the Japanese Geoparks-

Sun. Jun 6, 2021 5:15 PM - 6:30 PM Ch.02

convener:Noritaka Matsubara(Graduate School of Regional Resource Management, University of Hyogo), Kyohei Sano(Graduate School of Regional Resource Management, University of Hyogo), Suzuka Koriyama(Itoigawa city), Hikaru Yokoyama(Hokusho University)

5:15 PM - 6:30 PM

[O02-P19] The foundations of Yuzawa Geopark: a unification and a compilation of six geological maps published by the Geological Survey of Japan and Akita Prefecture

*Akio Sasaki1, Kohei Yamawaki1, Yukio Fujimoto1, Syoichi Goi1, Shoei Chiba1 (1.Network of Earth Science Museum for Akita)

Keywords:Geopark, Formation names, Fossil, Pyroclastic rock, Radiometric dating, Seamless geological map

The Yuzawa Geopark consists of approximately 300 geosites in the Yuzawa city, which are covered by six geological maps published by the Geological Survey of Japan and the Akita Prefecture.

It is difficult to understand geological events in this region using these maps alone, because of the different formation names at the same period, no-radiometric dates of volcanic rocks, and various coloration in these maps.

We began to work the project of the unification and compilation of six geological maps in 2017. During this project, we gathered the published papers including radiometric dates, preformed the geological field survey, collected fossils and rocks, and reconstructed the standard stratigraphic column for the study region. Based on these data, we compiled the distributions of formations from the same age in the study region.

The seamless geological map (B0 size) and a corresponding 226 page report were completed in 2020. These works provide valuable information including eruption ages of volcanic rocks from the Oligocene to the Pleistocene, and also newly discovered locations of molluscan and plant fossils. The seamless geological map and the report are useful for making the geo-story of geosites in the Yuzawa Geopark in near future.

References
Ozawa A. et.al. (1961)Uzenkanayama, (1979) Yuzawa, (1979) Asamai published by Geological Survey of Japan.
Usuta M. et.al. (1979)Yokote, (1981) Inaniwa, (1982) Akinomiya-Kurikomasan published by Akita Prefecture.
Takashima K. et.al. (1999) J. Min. Petr. Econ. Geol. Vol.94, p.1-10,
Kondo H.et.al. (2004) Island Are.vol.13, p.18-46.