Collection, Documentation and Dissemination of Strong Motion Data From Recent Large Earthquakes in Japan

该项目的目标是收集并提供日本近期大地震的数字强震记录；记录资料的来源、路径和地点参数，以便解释和使用数据；将其与美国使用的衰减关系进行比较；并就它们与美国地面运动的相关性提供评论。目的是为地震工程研究界提供基础数据。在1993年1月15日至1995年1月17日的两年间，日本发生了五次大地震，并有广泛的记录。这些地震中最小的是1995年1月17日发生的6.9级神户地震，由于发生在人口密集的城市地区，造成的破坏最大。其他四次地震的震级在7.5到8级之间。1、发生在俯冲带，而且都比美国有强震记录的任何一次地震都要大。这些强震数据很难获取，美国的大多数调查人员也不知道如何获取这些数据。此外，这些数据不能直接用于开发经验地面运动模型，因为与美国相比，日本使用的震级不同（日本地震震级而不是矩震级）；日本使用的是震中距离，而不是离断层最近的距离。这些情况导致这些潜在的有价值的强震数据利用不足。本项目包括以下内容：收集数字强运动时间历史以及解释和使用时间历史所需的许多类别的信息。包括地震矩、震源机制、构造类型等震源参数；描述到记录地点最近距离的路径参数；以及记录地点的地质技术数据。2. 利用这些数据，c将日本的地面运动与美国使用的相应经验衰减关系进行比较。在此比较的基础上，准备一篇关于记录的评论，描述它们对美国特定震源区的适用性。数字时间历史、参数信息、比较和评论将被存档在互联网上，并提供给位于科罗拉多州博尔德的国家地球物理数据中心。拟议的工作将执行1993年强震数据国际讲习班关于传播日本最近地震的强震数据的所有主要建议。＊＊＊

9527929 Somerville The objectives of this project are to gather and provide access to digital strong motion recordings from recent large Japanese earthquakes; to document the source, path and site parameters required for the interpretation and use of the data; to compare them with attenuation relations used in the United States; and provide commentary on their relevance to ground motions in the United States. The aim is to provide basic data for use by the earthquake engineering research community. In the two year period between January 15, 1993 and January 17, 1995, five major earthquakes occurred and were widely recorded in Japan. The smallest of these earthquakes, the magnitude 6.9 Kobe earthquake of January 17, 1995, was the most damaging because of its occurrence in a dense urban region. The four other earthquakes, with magnitudes in the range of 7.5 to 8. 1, occurred in subduction zones, and were all larger than any earthquake in the United States for which we have strong motion recordings. These strong motion data are difficult to acquire, and most investigators in the United States do not know how to acquire them. Further, the data cannot be directly used in the development of empirical ground motion models because different magnitude scales are used in Japan as compared to the USA (JMA magnitude instead of moment magnitude); and epicentral distance is used in Japan instead of the closest distance to the fault. These conditions result in the underutilization of these potentially valuable strong motion data. The project involves the following: 1. Gather digital strong motion time histories together with the many categories of information that are required for the interpretation and use of the time histories. These include source parameters such as seismic moment, focal mechanism and tectonic category; path parameters describing the closest distance to the recording site; and available geotechnical data from the recording sites. 2. Using these data, c ompare the Japanese ground motions with corresponding empirical attenuation relations used in the United States. 3. Based on this comparison, prepare a commentary on the records describing their appropriateness for particular seismic source regions in the United States. The digital time histories, parameter information, comparisons, and commentary will be archived on the Internet and provided to the National Geophysical Data Center in Boulder, Colorado. The proposed work will implement all of the major recommendations of the 1993 International Workshop on Strong Motion Data concerning the dissemination of strong motion data from recent earthquakes in Japan. ***