The Video about the Origin of Aso Caldera
Translation
Mt. Aso is one of the world’s largest calderas.
The diameter is approximately 20 kilometers.
A caldera is a Portuguese word meaning “Big Pan.”
See, it has the same shape, doesn’t it?
The caldera was formed by volcanic activities in ancient times.
These activities began about 300,000 years ago. About ninety thousand years ago, a great eruption occurred at Mt. Aso, causing a lot of pyroclastic flows.
Later, the ground sank, creating a large natural depression.
This is a caldera.
Then, new volcanoes appeared in the caldera.
Over tens of thousands of years, the ground collapsed and rainwater eroded it, forming the present Mt. Aso.
On the caldera and the slopes of the Five Aso Cones are green fields.
They are covered with grass called Sogen, which means green field.
Sogen in Aso is the most beautiful in all of Japan. It covers about 20,000 hectares.
It is as large as 20,000 soccer fields.
In the center of Kyushu, halfway between Kumamoto and Beppu, Mount Aso National Park includes the gigantic caldera of Mount Aso, formed when the volcano collapsed some 80,000 years ago. With a circumference of 75 miles (120 kilometers), it is among the largest in the world.
The town of Aso (population 30,000) lies to the north of this vast depression, which contains a dozen villages with a total population of about 100,000. The fertile slopes are covered with lush grazing pastures, terraced fields, lakes, forests, and hot springs used for onsen. Within the caldera are five volcanic cones: Naka-dake (4,941 ft / 1,506 m, the only active one of the five), Taka-dake (5,223 ft / 1,592 m, the highest), Neko-dake (4,619 ft / 1,408 m, recognizable by its craggy peak), Kishima-dake (4,167 ft / 1,270 m), and Eboshi-dake (4,386.5 ft / 1,337 m).
Classified as a “gray” volcano—one that sporadically sends up hot clouds of ash and scoria—Naka-dake has erupted almost 170 times. The oldest recorded eruption dates back to 553. More recent eruptions occurred in 1884, when ash fell on Kumamoto, and in 1933 and 1957, which were equally powerful. The most recent eruptions were in 2005 and 2007.
This is still a dangerous place; visitors have been hurt, and even killed, by falling rocks and sulfurous emissions (not recommended for those with respiratory problems). Check with the authorities if you plan any walks in the vicinity.