有馬型温泉水とスラブ脱水

抄録

Arima-type hot spring waters that exhibit unique geochemical characteristics and their formation are reviewed based on subduction-zone-scale perspectives and studies concerning fluid circulation. Arima-type hot spring waters produced in non-volcanic regions exhibit properties similar to those of volcanic fluids. In order to clarify the formation mechanism, we first review the definition of volcanic/non-volcanic regions and their essential differences. Then we discuss the dehydration reactions in the subducting plates, the resulting distribution and geochemical characteristics of slab fluids, and present evidences of their ascent into the Japanese crust and their role in the global material cycling. In addition, the characteristics and causes of the recently discovered Arima-like hot spring water in the Eurasian continent are reported, and the extent of the material circulation in the wide subduction zone is discussed.