山梨県増富鉱泉およびその周辺に湧出する温泉水の化学組成

抄録

Na, K, Mg, Ca, Cl, Br, SO₄, HCO₃ and H₂SiO₃ in Masutomi spring and other Northern Yamanashi spring waters were determined. Masutomi spring showed very high salinity. On the basis of the deviation from the sea water defined in concentration (ppm) as δ_X= (C_X/C_Cl-C_X,sea/C_Cl,sea)×100(%), δ_T= Σ|δ_X| where X=Na, K, Mg, Ca and SO₄, Masutomi spring water seems to be very similar to sea water in the compositions : the equivalent quantities of the depleted compositions (Mg, etc.) are well balanced by those of enriched ones (Ca, etc.) indicating some interactions between the sea water and surrounding rocks. On the point of view, Masutomi springs can be classified into three categories: the equivalent ratios of SO₄ to Cl are (1) equal to, (2) more than, and (3) less than the ratio in sea water. Therefore, it suggests that dissolution or precipitation of gypsum could be occurred.