Chichibu Geopark

Basic points

The strip-like white patterns running in succession inside the metamorphic rock (en echelon vein) is called a Gankomyaku (literally means "the vein of the flight formation of geese" in Japanese) as it evokes an imagery of wild geese flying in succession.

An en echelon vein is a crack that occurs in the process of rock rising from deep underground, and the gap of the crack is filled with white quartz and calcite.