中央氣象局地震測報中心自1990年起,推動建立全省的強地動觀測計畫。預定設置1000部加速度型強震儀來收集強地動資料,以進行地震災害分析。到目前為止已經有六百多部自由場的強震儀於全省監測地動情形。為維護儀器正常運作及資料收集方便,強地動觀測計畫將全省分成四個區域,分別由不同的大學與研究單位負責資料收集的工作。本所負責的中部地區(面積約150公里×140公里)包括180個強震站,其中桃園縣23站、新竹縣25站、苗栗縣29站、台中縣50站、彰化縣30站及南投縣23站。計畫主要的工作包含下列幾項:1)儀器維護2)資料收集3)背景雜訊分析4)基本分析與資料整理,其目的是希望能夠收集高品質的強震資料,並使整個系統運作更為順利,以提高可信度。 除了野外資料收集之外,我們也進行一些基本的分析。根據這幾年來的紀錄,可以檢測並評估系統的效能。另外,不同地區的PGA、PGV、PGD也可得到。利用Boatwright’s(1991)所提出的觀念,可以將震源、場址及路徑的效應分離;由分離的場址效應顯示與區域地質有關。這是相當有趣的研究,值得做更進一步的努力。 The earthquake center of Central Weather Bureau has set up a program to promote the observation of earthquake strong motion over Taiwan island since 1990. The purpose is to establish a 1000 station system to collect reliable strong motion data for earthquake hazard analysis. Half of these instruments (600 pieces) are deployed on the free field to monitor the ground motion. In order to maintain the instrument and collect the data, the system has been divided into 4 areas, and distributed among the universities and research institutes to share the responsibility. Our research group is in charge of the Central Taiwan which has 180 stations with an area of 150 km × 140 km. This region includes the counties of Taoyuan (23), Hsinchu (25), Miaoli (29), Taichung (50), Changhua (30) and Nantou (23). The task of this project includes: 1) instrument maintenance, 2) data acquisition, 3) background noise analysis and 4) documentation and basic signal analysis. All of these efforts will direct toward collecting high quality strong motion records and making the system operate smoothly and reliably. Except the field data collection, we also performed several basic data analysis. By using these years’ data, we reviewed and evaluated the performance of the system. The space distributions of PGA, PGV and PGD in different areas are investigated. Some techniques to separate the source, site and path effect of Boatwright’s (1991) type are also tested. The isolated site effects show consistent variation with local geology. This is an interesting study and worth further effort. 研究期間:9601 ~ 9612