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Daisen-Oki NP, Shimane
Claim this place to tell your story your way.
A 2.3-metre oarfish hangs in the museum’s sea-life corner. Caught off Goka in June 2023, it still has a rare detail intact: a light-producing organ on its long pelvic fin.
In Oki’s traditional sumo, the same wrestlers meet twice, and the first winner deliberately yields the rematch, ending 1–1. Since top ranks represent settlements, not individuals, the custom helps prevent village grudges.
Chemical fingerprints let researchers identify Oki obsidian in tools found as far away as Niigata and Shikoku. The museum traces this exchange back at least 30,000 years, when Oki was the Chūgoku region’s only source of tool-quality obsidian.
Oki’s gneiss records a remarkable deep past: its original rock formed about 2 billion years ago, then was transformed by heat about 250 million years ago. It’s a clue that Oki was once part of the Eurasian continent.
Oki’s ecosystem displays reveal an unexpected mix: northern rugosa roses, southern orchids, alpine plants and Ice Age survivors can grow near the coast. Why these very different plants coexist is still not fully explained.
A diagram added to the museum’s geology exhibits explains mantle xenoliths: fragments from deep beneath Earth’s crust, swept upward inside rising magma. Oki’s volcanic rocks preserve these rare clues to the planet below our feet.
