Aerial photographs were used to decipher buildings that collapsed, were buried, washed away, or were deformed by the sediment disaster that occurred with the 2024 Noto Peninsula earthquake (referred to as “collapsed buildings” in this report). In addition, the occurrence of human damage was estimated based on newspaper and television reports and various geographical information. 37 collapsed buildings were decoded, and 26 people were estimated to be dead or missing in at least five of these locations. 34 of the 37 collapsed buildings were located in areas where hazard maps indicate a risk of sediment disasters, such as sedimentrelated disaster risk areas. Sediment-related disaster risk areas are designated in anticipation of sediment disasters caused by heavy rainfall. However, the results of this survey suggest that information on sediment-related disaster risk areas may also be useful for earthquake-induced sediment disasters.

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Buildings washed away by the tsunami generated by the 2024 Noto Peninsula earthquake were identified from aerial photographs and field surveys. Based on newspaper and television reports, various geographic information, and field surveys, we estimated the circumstances under which the earthquake's fatalities and missing occurred. The most severe damage occurred in Horyu-machi, Suzu City, where 17 houses washed away by the tsunami were deciphered. In this area, 167 collapsed houses were deciphered as a result of the earthquake, and the damage to houses caused by the tsunami was limited compared to the damage to houses caused by the earthquake. The number of fatalities that occurred in the tsunami inundation areas was estimated to be about 25. About five of these fatalities are estimated to have been caused primarily by the tsunami. Most of them occurred in Horyu-machi, Suzu City. The ratio of fatalities to the population in the tsunami inundation zone in this district was estimated to be 0.38%. This ratio is about the same as that of the area hit by a tsunami of the same magnitude in the Great East Japan Earthquake.

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The Kaetsu region, Niigata Prefecture, experienced record-breaking heavy rainfall between the 3rd to 4th August 2022 that originated from stagnated linear rainbands. Intense rainfall up to 150 mm h^-1 resulted in numerous shallow landslides on mountain slopes, with a landslide area rate（ normalized cumulative area of landslides per unit area of landform） of 8.3%. In addition, hyperconcentrated flow with large woody debris in the Osawa River reached the hamlet of Koiwauchi, Murakami city, late at night. Fortunately, there were no fatalities caused by the event. However, damming of the channel by large woody debris resulted in the destruction of several houses along the river and inundation of the surrounding area. Evacuation of residents in Koiwauchi was initiated by the local government, based on flood alert information rather than landslide alert information. This was key to obtaining sufficient lead time for a successful evacuation. In Koiwauchi, the lessons learned from the 1967 Uetsu flood disaster and the training program for disaster prevention expert facilitated by Murakami city were instrumental in bringing about effective and appropriate evacuation behavior.

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From June 2 to 3, 2023, heavy rainfall exceeding 400 mm of accumulated precipitation was observed from Kochi to Kanagawa Prefectures due to Typhoon No.2 and Baiu-front. In the Kanto region, 286 mm of precipitation was observed in Toride City in southern Ibaraki Prefecture. Futaba Danchi in Toride City suffered internal flooding with a maximum flood depth of 1.2m due to overflowing water from surrounding waterways, resulting in 324 houses half destroyed and 240 houses flooded under the floor out of 1,120 houses. In the Futaba area, where housing construction began in 1966, the population and aging population are now rapidly declining. For this reason, evacuation support for persons requiring support for evacuation action, etc., is being reconsidered.

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In this paper, we proposed a seismic intensity increment evaluation formula using the parameters of the fundamental peak of microtremor H/V in order to accurately evaluate seismic intensity increments even at locations where the exact average S-wave velocity structure is unknown. First, we derived an approximate expression that simplified the relationship between the earthquake ground motion spectrum and the seismic intensity increment. Calculated values and approximate values of seismic intensity increments were estimated for various earthquake magnitudes and pseudo site amplification effects, and it was shown that these values correspond well. In addition, it was shown that the seismic intensity increment can be evaluated to some extent by considering only the fundamental peak of the site amplification effects for the seismic stations targeted in this study. Next, seismic intensity increments and site amplification effects were evaluated for seismic stations in the Chugoku region and other areas. We also found an empirical formula for evaluating seismic intensity increments using the parameters of the fundamental peak of site amplification effects, and showed that seismic intensity increments can be evaluated with good accuracy. Finally, we obtained an empirical seismic intensity incremental evaluation formula using the parameters of the fundamental peak of microtremor H/V. As a result, it was clarified that the seismic intensity increment can be evaluated with good accuracy, although the prediction accuracy is lower than when using the site amplification effects.

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