Earthquakes generally occur along active faults. In addition, it must be considered that disasters due to tsunami and liquefaction may occur in coastal areas and soft ground areas. Therefore, the assessment of the earthquake hazards should be carried out based on the knowledge of earth science. And combining with earthquake observation networks, and simulations of seismic intensity and tsunami height, we can estimate earthquakes, tsunamis, and liquefaction hazards that may occur in the future.