Extracting the area where people have difficulty evacuating (hereafter difficult-to-evacuate areas, DEA) when tsunamis hit after an earthquake is important for effective disaster mitigation measures. The DEA was conventionally extracted by simply considering the walking speed, distance to the evacuation destination, and time needed for evacuation after considering the estimated tsunami inundation area. However, evaluating the DEA from such a simple scheme is insufficient because the behavior of residents and the road conditions to the evacuation destinations after an earthquake are not properly reflected in the scheme.

In this study, agent-based tsunami evacuation simulations that can reflect the behavior of residents and real-time changes in the situation were conducted in Zihuatanejo, Guerrero, Mexico. It is a prime sightseeing destination under the high risk of megathrust events in the Guerrero Gap. First, by checking the simulation images at the tsunami arrival time, bottleneck locations were identified, and five additional models with different measures for the bottleneck locations were constructed and tested to find the best model with 195 casualties. Then, focusing on the best model, three indices for the casualties were proposed to extract the DEA effectively and quantitatively, and numerical analyses using the three indices was conducted. Finally, the subdistrict in the center of the target area (subdistrict 5) was quantitatively found to be the district that should be given the highest priority for measures. Moreover, an example model with a new measure in subdistrict 5 was validated to have 101 casualties. The key points for applying the proposed method for extraction of DEA in other areas are summarized.

提取地震后发生海啸时人们难以疏散的区域（以下简称难疏散区域，DEA）对于有效的减灾措施很重要。传统上，在考虑估计的海啸淹没区域后，通过简单地考虑步行速度、到疏散目的地的距离和疏散所需的时间来提取 DEA。然而，从这样一个简单的方案评估 DEA 是不够的，因为该方案没有正确反映地震后居民的行为和疏散目的地的道路状况。

在这项研究中，在墨西哥格雷罗州芝华塔尼欧进行了基于代理的海啸疏散模拟，可以反映居民的行为和情况的实时变化。在格雷罗峡谷发生超大逆流事件的高风险下，它是一个主要的观光目的地。首先，通过检查海啸到达时间的模拟图像，确定瓶颈位置，并构建并测试了五个针对瓶颈位置采取不同措施的附加模型，以找到具有 195 名伤亡人数的最佳模型。然后，针对最佳模型，提出了伤亡人数的三个指标，以有效、定量地提取DEA，并利用这三个指标进行数值分析。最后，目标地区中心的街道（街道 5）在数量上被认为是应该给予措施最高优先权的地区。此外，在分区 5 中使用新措施的示例模型被验证为有 101 人伤亡。总结了将所提出的 DEA 提取方法应用于其他领域的关键点。