Geochemical Investigation of Waters on SENKAKU RETTO

K. KANESHIMA (1969) reported on chemical analyses of waters on the SENKAKU RETTO. The present authors made calculations based on his data and discussed behaviors of Na^+, K^+, Ca^2+, Mg^, H^+, C1^-, SO_4^, PO_4^, and HCO_3^-, in hydrosphere, atomosphere, and Iithosphere. As a result, they obtained new informations about water's history on the SENKAKU RETTO which may be summarized as follows: (1) All seven samples were supporsed to be made of land waters being mixed with sea water by some means on the each islands. The mixing rate of sea water for 1 liter of land waters is 1/140 liter for sample No. 1, 1/100 liter for No.2, 1/100 liter for No.3, 1/130 liter for No.4, 1/70 liter for NO.5, 1/80 liter for No.6 and 1/60 liter for No.7. (2) Although four samples (No.1~No.4) on the UOTSURI JIMA were collected from almost same locality, the water's history was different. (3) For two samples (No.6 and No. 7) on the KITA KOJIMA, the composition of land water which was mixed with sea water was almost the same. Therefore, the history of No.6 and No.7 was alike. (4) Although sample No.5 on MINAMI KOJIMA was collected from a large of guano, like No.6 and No.7. the composition of land water which was mixed with sea water for making up No.5 was different from the composition of land waters for No.6 and No.7. Therefore, the history of No.5 was different from No.6 and No.7. (5) In sample No. 1 and No.5, the results of balance calculation of cations and anions which came from land waters point out that quantity of cation is excess over anion. The reason why pH of No.1 and No.5 was acidic can not be explained. (6) Enrichment coefficient of Na^+ in a sea water spray is 1.0 or larger than it