Composition and origin of modern hydrothermal systems of the Kuril island arc

166-180The resent study consists the original geochemical data on the thermal waters of the Kuril Islands (Mendeleev, Golovnin, and Ebeko volcanoes) and relation between thermal waters and ore formation. Among the thermal water types three main groups can be distinguished: sodium–chloride, acid sulfate and chloride-sulfate-bicarbonate. The contents and behaviors of siderophile, chalcophile, lithophile, and rare-earth elements are discussed. These data, together with the result of isotopic studies, enumerates the origin of these waters. The high-temperature sodium-chloride waters have a profound effect on the formation of copper-pyrite mineralization on Mendeleev, Ebeko and Baransky volcanoes. The acid waters influence the processes of hypergenic ore formatio

The composition of groundwaters of Muraviov-Amursky Peninsula, Primorye, Russia

193-199Seawater intrusion, composition and quality of the shallow ground water in the south of Primorye region had been investigated. The Muraviov-Amursky peninsula is a middle mountain area (up to 400 m). The rocks in this area are presented by Permian volcanic, sedimentary, and granite rocks as well as Triassic sediments. Water had been included in a fracturated zone. The water table is located at depths ranging from less than 1 meter to more 20 m. The changes is depending on seasonal and atmospheric precipitation that varies between 1000-1200 mm/y. Values of pH ranging from 5.4-8.4, main ions composition is mixed with HCO₃-Ca, Na – in granite rocks. Sea water intrusions had been examined by chemical and stable isotopes data