How did Japan's archipelago form?

Explanation:

Most archipelagoes are made of oceanic islands. This means the islands were formed by volcanoes erupting from the ocean floor. ... The Japanese archipelago consists of four large islands, from Hokkaido, in the far north, through Honshu, Shikoku, and Kyushu in the far south.

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Volcanoes.

Explanation:

There are many theories about this, though Japan was not discovered until the Chinese stumbled upon it, trying to find a potion of immortality(yes, I know, it sounds silly) and BOOM, Japan was Japan. I personally suspect volcanoes since for volcanoes to go extinct, they must have spewed a LOT of lava. Take mount Fuji, an dead volcano. it probably accounted for making about 13% of Japan's landmass. Also, since water goes down during the winter, Japan might have even existed back in the Ice Age.

answer; /// the above statement is ( true);

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