noun
circum-Pacific seismic zone; Ring of Fire
Geological term for the belt of frequent earthquakes and volcanic activity around the Pacific Ocean.
日本は環太平洋地震帯に位置している。
Japan is located in the circum-Pacific seismic zone.
環太平洋火山帯 specifically refers to the volcanic belt, while 環太平洋地震帯 emphasizes the seismic (earthquake) aspect. Both are often subsumed under the 'Ring of Fire' concept.
Compound of 環太平洋 (circum-Pacific) + 地震 (earthquake) + 帯 (belt/zone).