Geochemistry of recent hydrothermal systems of Mendeleev Volcano, Kuril Islands, Russia

Among the thermal waters of Mendeleev Volcano three main types can be distinguished: sodium-chloride, acid-sulfate and chloride–sulfate–bicarbonate waters. Contents and behaviors of siderophile, chalcophile, lithophile, and rare-earth elements are discussed. These data, together with the result of isotopic studies (oxygen and hydrogen), are used to discuss the origin of these waters. From the three types of thermal waters, only acid-sulfate waters have a significant input on the chemical composition of the surrounding surface waters.     

V.I. Vernadsky and main research avenues in modern hydrogeochemistry

The main research directions in modern hydrogeochemistry were analyzed in connection with the 75th anniversary of its foundation. It was shown that hydrogeochemistry has fruitfully developed on the basis of the scientific concepts of its founder, V.I. Vernadsky. Among these concepts are the mineralogy of water, evolution of the system of water-rock-gas-organic matter, dynamics of hydrogeochemical processes, isotopic and environmental hydrogeochemistry, geochemistry of free and capillary waters, ocean geochemistry, geological and biological role of water, physicochemical modeling, etc.     

Chemical composition of precipitation in the southern part of the Russian Far East

Distribution of macro-and microelements, found in precipitation in dissolved and suspended forms (solid material) is considered. Contribution of the main sources of substance input in the precipitation on the investigated area is assessed.     

Diatoms from Bottom Sediments of Karakel’ Lake (Central Caucasus) and a Reconstruction of Regional Climate Events in the Late Holocene

Data on diatom complexes from bottom deposits of Lake Karakel’ (the Karachayevo-Cherkessian Republic) have been analyzed. The principle of unification of bioindication methods has been applied. The hydrological parameters of lake water (temperature, pH, and saprobithy) have been reconstructed over a period of 2000 years. The results of isotopic dating of bottom sediments have been used. For the first time for the Central Caucasus, the current and Late Holocene diatom alga complexes have been described. Photographs of the most abundant and significant lower taxa of diatom algae are given.     

Isotopes of sulfide and sulfate sulfur in nitrogen hot springs of the Bauntov group (Baikal Rift Zone)

Doklady Earth Sciences -     

中国东北与俄罗斯远东富CO_2矿泉水化学对比

中国东北与俄罗斯远东富CO2矿泉是宝贵的饮用、医用矿水资源。五大连池、长白山天池、俄罗斯远东Primorye地区各泉水水化学特征对比显示,中国东北五大连池与俄罗斯远东Primorye地区出露泉水为低温、微酸、HCO3型、富含Si、Fe、Sr和CO2气体的综合优质饮用矿泉水;长白山天池出露泉水为高温、中性-微碱、HCO3型、富含Si和CO2气体的优质热矿泉水。五大连池和俄罗斯远东富CO2冷矿泉与长白山天池富CO2热矿泉具有相似而不同的形成过程,CO2气体对水化学的形成起了决定性的作用,广泛发育的花岗岩提供了富CO2热泉的物质来源,断层破碎带增加了CO2气体-地下水-花岗岩之间的反应程度,温度仅对可溶性Si有影响。     

Fe-Mn crusts from underwater rises of the Kashevarov Trough (Sea of Okhotsk)

Dredging on nonvolcanic underwater rises in the Kashevarov Trough area (Sea of Okhotsk) carried out during Cruise 178 of R/V “Sonne” yielded sedimentary (conglomerates), metamorphic (biotite hornfels, tectonic breccia with inclusions of biotite hornfels), and igneous (granodiorite) rocks as well as Fe-Mn crusts up to 15 cm thick. The study of the structural-textural properties and the thorough analysis of the mineral and chemical compositions of these crusts, including the REE and Y distribution, show that the ore sediments are hydrogenic in nature.