![](https://www.oki-geopark.jp/wp/wp-content/uploads/2023/03/Kuboro-Beach-Mantle-Xenoliths-900-1.jpg)
Geohistory - Rocks from Volcanic Islands Period
Geosites / Okinoshima Town
You can see various types of rocks on Kuboro Coast. Among these, some contain mantle xenoliths—a piece of Earth's mantle contained inside volcanic rocks. These are a precious resource for us to observe from the surface the inner parts of the Earth, deeper underground than humans have managed to reach.