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Significant liquefaction damage was confirmed in areas affected by the Noto Peninsula earthquake. Experts have noted that liquefaction can happen anywhere, forcing us to reconsider how we should prepare for damage. Images of the city of Uchinada in Ishikawa Prefecture during the earthquake show the city suffering from strong shaking. As the pavement seemed to crack and float, murky water rushed over the edge. During the earthquake in the Noto Peninsula, a phenomenon similar to “liquefaction” occurred in many places. A month has passed since the earthquake struck, and liquefaction still leaves a huge mark on the affected area, which is gradually recovering. We asked Associate Professor Shuji Moriguchi of Tohoku University’s International Disaster Research Institute, who studies geological disasters and who also conducted field research in Ishikawa Prefecture, about the mechanism behind this. Shuji Moriguchi, associate professor at the International Disaster Research Institute of Tohoku University: “The soil on which you build your house, walk and run is solid, but when an earthquake occurs, the groundwater there rises high and loosens. A phenomenon in which the earth becomes soft like water.” In other words, the ground that supports buildings is made up of a mixture of sand, soil, groundwater and air, and under normal conditions the grains of sand are mixed together. together they support each other, and between them there is air and groundwater. When the earth is shaken by an earthquake, the grains of sand that supported each other disintegrate and float in the groundwater. Over time, heavy objects will sink and light objects will rise. During this time, liquefaction is a phenomenon in which the soil subsides and groundwater, dirt and sand rush to the surface. Shuji Moriguchi, assistant professor at the International Disaster Research Institute of Tohoku University: “For example, the hatch is hollow inside, so it is generally heavy, but because it is hollow, it rises up from the ground. This liquefaction also took place. confirmed during the Great East Japan Earthquake in 2011. The Arahama district of Watari City in the southern part of the prefecture. According to Sayaka Sato, the facility where she was working at the time suffered from liquefaction. Sayaka Sato: “The water rushed out so fast that I thought the water pipe had burst and sand was pouring out, so it felt like the city was bumpy. Liquefaction has distorted the city. Looking back, Mr. Sato says his “evacuation actions” immediately after the disaster had a significant effect. Sayaka Sato: “Not being able to use roads (due to liquefaction) is a life-threatening situation, so I want people to remember that this kind of phenomenon still exists.” Tohoku University, studying geotechnical engineering. Akira Kamura of the Graduate School of Engineering notes that what happened in the earthquake-hit area of the Noto Peninsula could have happened anywhere in the country. Associate Professor Akira Kamura, Graduate School of Engineering, Tohoku University: “It is possible that similar liquefaction could occur within the prefecture (in the future).” On the other hand, there are also difficulties in taking countermeasures. Associate Professor Kamura says that beyond cost considerations, there is a need to improve the area in each area. Associate Professor Akira Kamura, Graduate School of Engineering, Tohoku University: “If you ignore the cost aspect, you may have the option of improving human settlements, but in addition to the cost aspect, you can also improve the infrastructure that is currently in place. It is an unrealistic story to temporarily stop a moving society and improve it.” So how do we prepare? A map created by the prefecture showing the risk of liquefaction is published on the prefecture’s website so you can see where the risk is high. Based on this information, Associate Professor Kamura believes it is important to “understand the risks correctly and imagine what will happen.” Associate Professor Akira Kamura, Graduate School of Engineering, Tohoku University: “Electricity, gas and water supply systems may be affected by liquefaction caused by ground shaking, ground subsidence or flow, ruptured water pipes or power supply. In such cases, it is important to consider whether we can prepare for the time when public help and support arrives.” “Disasters that don’t know when or where they will happen are important. It is important to treat this as your own business.