The 2018 Hokkaido Eastern Iburi Earthquake and its Aftermath

Abstract

The central Hokkaido, Northern Japan, was struck by an earthquake of M6.7 on September 6, 2018. Its deep hypocenter of 37 km might result of a complex crust and upper mantle structure in Hidaka arc-arc collision system. A seismic intensity of 7 on the Japan Meteorological Agency (JMA) scale was observed at Atsuma Town. About 90% of the casualties were due to the multiple earthquake-induced landslides in Atsuma Town, and a significant number of houses in the urban areas of Sapporo were damaged due to soil liquefaction. Destruction of electric power facilities near the epicenter caused a long-term power outage in approximately 2,950,000 houses in Hokkaido. The widespread blackout caused secondary damages to utilities, civil life, and economic activities in the region. The number of refugees from this incident was approximately 13,111 in maximum, and the economic damage also increased further as a result of the electric blackout. The Hokkaido Prefectural Government immediately applied the Disaster Relief Act on that accrual day. On September 28, 2018, the National Government certified the event as the Designated Disaster of Extreme Severity.