About Kirishima Geopark

The Kirishima Geopark is the region centered around the Kirishima Mountains, which consist of more than 20 volcanoes dotted within a 30-kilometer x 20-kilometer area extending northwest and southeast in Miyazaki and Kagoshima Prefectures. Here, you can feel the history of volcanic activity spanning from before the prehistoric ages through the historic ages to the present, and the diversity of nature that has been nurtured by this history.

About Kirishima Geopark

In the Kirishima Geopark, you can enjoy the view of the Kakuto Caldera and the Kirishima Mountains that grew up on its southern edge. The area of the Kirishima Geopark is encircled by the JR Hisatsu Line, the JR Kitto Line, and the JR Nippo Mainline. Within this area lies varied terrain including a mountain region with wildly undulating mountains stacked atop each other, flat basins spreading out at the foot of the mountains, and deeply cut gorges and vertical cliffs. Approximately 420,000 people live in the 2,600 square kilometer area straddling parts of Miyazaki prefecture (Miyakonojo, Takaharu, Kobayashi, Ebino) and Kagoshima prefecture (Kirishima, Soo, Yusui).

The Theme of the Kirishima Geopark

diverse nature and the volcanic activities that nurture it

1. Volcanic Activity of the Kirishima Mountains

The Kirishima Mountains is the general term for the cluster of volcanoes that formed through tens of thousands of years of volcanic activity on the south side of the Kakuto Caldera, which was formed in a catastrophic eruption about 340,000 years ago.

Beginning with the Kirishima Mountains, the volcanoes of southern Kyushu form a line from south to north, and from the peaks of Kirishima such as Mt. Karakunidake one can look out to the south and see the Aira Caldera, Sakurajima, and Mt. Kaimondake spread out in a row. This line of volcanoes runs parallel to the Nankai Trough east of Kyushu, and the Kirishima Mountains are a place where one can learn and see with one's own eyes the formation of volcanoes along converging plates.

The Kirishima Mountains, formed after the formation of the Kakuto Caldera, are some of Japan's active volcanoes that have been active for the last 200,000 years. This volcanic activity has created more than 20 volcanoes crowded into a narrow area of 20 kilometers X 30 kilometers. Along with the view of the line of volcanoes of southern Kyushu is this view of the magnificent geologic formation of this volcanic cluster.

Volcanoes of various shapes were formed by the eruptive activity of Kirishima.

The Kirishima Mountains of southern Kyushu, whose name literally means "fog island" and with peaks exceeding 1,000 meters in elevation, has high amounts of precipitation and is brimming with rich stores of underground water. It is surmised that the relatively large number of large diameter volcanic craters and volcanic crater lakes of Kirishima, such as that of Mt. Shinmoedake, were formed by the explosive power of repeated phreatic eruptions in the past, which were caused when magma rose up and touched this underground water.

Furthermore, a diverse selection of volcanoes exists here due to things such as different qualities of lava and shapes of eruption, including the acute silhouette of Mt. Takachihonomine and the pyroclastic cone of Mt. Karakunidake. On top of this, many waterfalls and gorges are formed in the deposits of the pyroclastic flow of the Kakuto Caldera, which could be called the mother of Kirishima. Kirishima is a place where a diversity of volcanic shapes and ejecta can be observed.

2. Reasons of Botanical Diversity

Many of the mountains of Kirishima exceed 1,000 meters in elevation, and the average temperature of the Ebino Plateau is similar to that of the southern Tohoku region of northeast Japan. Fagus crenata (Japanese beech), Quercus crispula Blume, Momi firs, and the Southern Japanese hemlock, plants that lived in southern Kyushu during the ice age still exist on the high peaks of the Kirishima Mountains that were formed by 15,000 years ago. At Kirishima, one can observe the vertical distribution of plants with the broadleaf forests at low elevations, deciduous and coniferous forests at high elevations, and plants such as Kyushu azaleas (miyamakirishima) at the timberline.

Each volcano exhibits a variety of plants due to being in various stages of transition following volcanic activity, including completely barren areas around a volcano, areas with pampas grass and Kyushu azaleas (miyamakirishima), and red pine forests. Furthermore, the natural habitat of Malus spontanea Makino, a national natural treasure, is a wetland that was formed when ejecta from the Mt. Karakunidake explosion crater flowed onto the mountainous basin of the Ebino Plateau, which was once rich with water.

It is said that there are 1,300 species of plants on Kirishima. Located in the damp climate of southern Kyushu, with peaks exceeding 1,000 meters and volcanoes formed in different eras, the volcanic activity of the Kirishima Mountains continues even now and helps maintain a diversity of plantlife.