One of Japan’s Youngest Mountains
Most people know that Japan is a country that has many earthquakes and volcanoes—after all, it’s on the Pacific Ring of fire—and is a geologically very active, and unstable, part of the world. The whole country is on the Pacific Rim, including the northern island of Hokkaido. So, on our last visit to Hokkaido it was fascinating to visit a new mountain, to see these forces of Nature at work. We had a chance to see how that activity has worked—a new mountain that pushed up, and for all we know is still growing.
Hokkaido has had a lot of volcanic activity, and you see many conical mountains that are supposedly dormant, and not extinct. One day, our hosts Satoshi and Max took us on a day trip south from Sapporo to visit the evidence of new volcanic activity.
In the south part of Hokkaido is Shikotsu-Toya National Park, which includes Showa Shinzan Special National Monument and Mount Usu, among other sights.
We went to the Showa Shinzan Special National Monument, just off Lake Toya. Lake Toya is a caldera lake created by a major volcanic eruption tens of thousands of years ago. Around the lake today is a hot spring region, with many spa facilities, and fertile soul for agriculture. There is also Showa Shinzan, sometimes called the “natural volcanic museum”. It’s a volcanic lava dome, next to Mount Usu. The story of this mountain shows that volcanic activity around here continues and it’s a hot spot for volcanic activity. And it’s a pretty amazing story.
The name Showa Shinzan means Showa new (shin) mountain (zan), as it formed during the reign of Emperor Hirohito, in the Showa period. The mountain was created between December 28, 1943 and September 1945. Initially a series of strong earthquakes shook the area from December 1943-June 1944 and wheat fields were uplifted. Next came the eruption phase, which lasted between the end of June 1944 and the end of October 1944, when lava broke through the surface. Lava reached the banks of Lake Toya, burning houses and forests in its path. Volcanic ash was deposited kilometers away, and the protuberance in the ground continued to grow. In the post-eruption phase (November 1944-September 1945) eruption activity stopped and the lava dome began to take shape and the current peak was created. It is now 1,306 ft (398m) tall and still actively smoking and gently steaming, so who knows what’s coming next!
Showa-shinzan first appeared during WW2 so the Japanese authorities were worried that it might be interpreted as an unlucky wartime omen, and therefore its existence was kept secret. Much of the information about the peak’s formation during these years comes from local postmaster, Masao Mimatsu, who kept detailed measurements of its progress. Those records are very important, with lots of geological information.
It was really interesting to see the new peak, smoking, and giving off a faint sulphur smell. The top of the new mountain is still barren: vegetation only starts growing slowly from the base. It’s a very pretty park, as there are woods below the mountain with many silver birch trees and plenty of bright green bushes. The day we were there the new mountain, reddish-orange in color, was glowing in the sunshine, so the view was like a landscape painting. Interestingly, the colors of the mountain changed a bit, depending on the vantage point and on the light, so sometimes it seemed more reddish and at others more yellowish.
There is a small Visitors Center to one side, with information on the development of this whole area. We were also fascinated to learn about certain animals that are unique to Hokkaido. Ezo is the old word for Hokkaido so these animals are known as Ezo higuma (bear), Ezo lisu (squirrel) and Ezo shika (deer), for example.
Lining the carpark are many small shops selling curios, souvenirs etc.
A ropeway takes you from near the foot of Showa Shinzan to the top of Mount Usu, with great views out over the area and the lake, but we didn’t do that.
Thanks again to Satoshi and Max for being such wonderful hosts!