自然災害如地震、山崩、土石流及火山爆發等,在發生過程中皆有超出人類的聽覺範圍之次聲信號(即頻率低於20 Hz的聲波)的記錄.次聲之頻率較一般地聲為低,故具有能量遞減慢及較少環境背景干擾的特色.次聲信號之特性與土石流或滑坡之土、石、水份組成及山坡地質條件有關,必須就地域特性進行比對及驗證,方能確定次聲信號與土石流事件之關聯性.鑒於台灣山區土石流及崩塌頻繁,屢屢造成交通中斷及生命、財產之損失,建立台灣本土性之坡地災害次聲監測系統是減免坡地災害之可行對策.藉由靈敏之次聲感應器、資料處理器及訊號處理系統,能接收經由空氣傳播之次聲信號來即時監控土石流及滑坡之發生,並發出預警訊息,以達到減災、防災的功能。Naturally occurring infrasound is produced by earthquakes, volcano eruptions, landslides and debris flows. Infrasound covers the inaudible acoustic spectrum below 20 Hz, which results from the compressibility of the air. Infrasound propagates to large distance in the atmosphere at the speed of sound for the low adsorption in the air and the high reflectivity of the ground. The infrasonic signals induced by landslides and debris flows are related to the magnitude and composition of the failure zone as well as the slope areas. In order to establish the monitoring system for the slope hazards in Taiwan, this proposed study will explore the infrasonic signals of landslides and debris flows by experiments and field study. The monitoring system includes the sensitive infrasonic transducers, data logger and signal processors. With the spectrum analysis, this infrasonic system can be implemented with the warning system in the potential debris flow areas. 研究期間：9201 ~ 9212
