1.前言最近,与地震发生有关的活动断层越来越引起人们的注意,并从多方面进行了调查和研究。其中,可称作地球化学信息的活断层周围物质的化学特性也是人们的研究对象之一。特别是从活动断层散发出来的气体成分的变化和地震活动的关系更是研究的一项内容。由于断层活动,上层物质和地下深处物质可能交流,地下深部气体就会因震前地壳形变而释放。例如,杉崎在1981年就用地壳形变和 He/Ar 变 1. INTRODUCTION Recently, active faults associated with earthquakes have drawn increasing attention and investigated and researched in many aspects. Among them, the chemical properties of the material around the active fault, which can be called geochemical information, are also one of the research subjects. In particular, the relationship between the evolution of gas components emanating from the active fault and the seismic activity is one part of the study. As a result of fault activity, the upper and lower subsurface materials may communicate, deep underground gas will be released due to pre-earthquake crustal deformation. For example, Sugitaki used crustal deformation and He / Ar transformation in 1981