How long did it take to form the Pothole in Joga-Shima Island?

Yusuke Izumi

Presentation information

[J] Poster

O (Public ) » Public

[O-04] Poster presentations by senior high school students

convener:Tatsuhiko Hara(International Institute of Seismology and Earthquake Engineering, Building Research Institute), Katsuyoshi Michibayashi(Department of Earth and Planetary Sciences, Nagoya University), Miwa Kuri(Japan Meteorological Agency), Keiko Konya(Japan Agency for Marine-Earth Science and Technology)

[O04-P61] How long did it take to form the Pothole in Joga-Shima Island?

*Yusuke Izumi¹ (1.Saitama prefectural Kasukabe High School)

Keywords:Joga-shima , Pothole, Earthquake, Trace fossils, Coastal terrace

Joga-shima Island is located at the southernmost tip of the Miura Peninsula. This island has been raised by the earthquakes that occurred in the past, and forms a coastal terrace. There are some potholes on the terrace. For one of them, I considered the formation period of the pothole from two records. One is the record of crustal movement during the 1703 Genroku Kanto earthquake and the 1923 Taisho Kanto earthquake. And another is the record of the trace fossils made by boring shells in my field survey. As a result, it became clear that the target Pothole had been formed for about 220 years from the 1703 Genroku Kanto earthquake to the 1923 Taisho Kanto earthquake.