Pacheon Orbicular Granite | 観光地情報 | K-Travel Mate

"Orbicular" refers to a texture where dark and light mineral layers alternate concentrically around a nucleus, forming a spherical shape, and "granite" is a rock formed by magma slowly cooling deep underground. Pacheon Orbicular Granite is granite containing such spherical structures. This granite was formed during the Triassic period (230 million to 180 million years ago). Contemporary organisms include ammonites. The Pacheon Orbicular Granite shows alternating growth of light-colored minerals (quartz, feldspar, colorless minerals) and dark-colored minerals (biotite and other colored minerals), resembling the layers of an onion. Such orbicular rocks are very rare, found in about 100 locations worldwide. (Source: Cheongsong World Geopark)