A new type of noble metal mineralization in the Northern Caucasus

The weathering crust of the Beden ultrabasite massif (the basin of Big Laba River) is identified and studied. Anomalously high contents of noble metals (Au, Pt, Pd) are revealed in the basal horizon of the Jurassic part of the weathering crust. For this reason we suspect an existence of a belt of noble metal miner-alization in the Paleozoic ultrabasites in the Peredovoi Range of the Northern Caucasus.     

Biogenic contribution of minor elements to organic matter of recent lacustrine sapropels (Lake Kirek as example)

An approximate biogenic contribution of minor elements to sapropel of Lake Kirek in West Siberia is estimated using the “model of direct inheritance” of their composition in plankton by OM of bottom sediments (Yudovich and Ketris, 1990). It is shown that the lifetime accumulation of P, Br, and Zn in copepod zooplankton of Lake Kirek notably affects the concentration of these elements in sapropelic mud (biogenic contribution is approximately 95–53%). The biogenic share of other elements in these sediments is substantially lower: approximately 30% for Sr and Ba; 26–16% for Ca, Pb, Cd, Cu, K, Mg, and Cr; and no more than 5% for As, Co, Fe, Ni, Ti, Y, and Mo.     

Mesocosm-Based Estimation of the Consequences of Complex Contamination of a Freshwater Body by Metal Salts

The dynamics of metal concentrations in the solution, suspension, sediments, and floating plants, as well as functional and structural parameters of phytoplankton and zooplankton were studied. The sorption rate of metals on suspension and the efficiency of their removal into bottom sediments decreased in the series Pb > Cu > Zn > Cd and at increasing proportion of metal aquaions in the solution. The effect of intensive renascence of green algae was recorded from the eighth to tenth day after the metal discharge into the mesocosms. This effect activated a plankton mechanism of metal removal into bottom sediments. The metal discharge led to a strong and stable depression in all groups of zooplankton.     

Geochemical characteristics of the modern state of salt lakes in Altai krai

A complex of analytical methods (atomic absorption spectroscopy AAS, synchrotron radiation X-ray fluorescence SR-XRF, and instrumental neutron activation analysis INAA) were used for analyses of 40 trace elements. In compliance with the conventional biogeochemical methods, enrichment factors EF were calculated for plankton relative to the average concentrations of elements in continental clay (shale) preliminarily normalized to Sc. In order to understand the concentration specifics of trace elements in living organisms inhabiting aquatic ecosystems of variable salt composition and geochemical characteristics, chemical speciation of elements was calculated for the brines of salt lakes by the WATEQ4F and Selektor-S computer programs. The enrichment of plankton in Hg in Lake Bol’shoe Yarovoe is caused not only by the chemistry of the mineralized brine (bittern), as follows from the Hg speciation in it, but also by anthropogenic contamination (Hg-bearing wastes from the Altaikhimprom chemical plants in the town of Yarovoe).     

Anomalous concentrations of zinc and copper in highmoor peat bog, southeast coast of Lake Baikal

When examining the peat deposit discovered in Vydrinaya bog, South Baikal region, the authors encountered anomalous Zn and Cu concentrations for highmoors being up to 600–500 ppm on a dry matter basis in the Early Holocene beds (360–440 cm) formed 11 000–8500 years ago. It has been demonstrated that Zn and Cu are present inside the plant cells of peat moss in the form of authigenic sulfide minerals of micron size. Apart from Zn and Cu, native Ag particles (5–7 um) have been encountered in the peat of the Vydrinaya bog at a depth of 390–410 cm; these particles formed inside the organic matter of the plasma membrane of peat moss containing Ca, Al, S, and Cu. This study suggests probable patterns of the formation of zinc sulfides, copper sulfides, and native silver in peat moss. The results obtained indicate that biogenic mineral formation plays a significant role in this system, which is a very important argument in the discussion on the ore genesis, in which physicochemical processes are normally favored, while the role of living matter is quite frequently disregarded.     

Concentration of chemical elements by zooplankton of the White Sea

A technique of net sampling of zooplankton at night in the Kandalaksha and Dvinskii Bays and during the full tide in the Onezhskii Bay of the White Sea allowed us to obtain “clean” samples without considerable admixtures of terrigenous suspension. The absence of elements-indicators of the terrigenous suspension (Al, Ti, and Zr) in the EDX spectra allows concluding that the ash composition of the tested samples is defined by the constitutional elements comprising the organic matter and integument (chitin, shells) of planktonic organisms. A quantitative assessment of the accumulation of a large group of chemical elements (approximately 40) by zooplankton based on a complex of modern physical methods of analysis is presented. The values of the coefficient of the biological accumulation of the elements (K_b) calculated for the organic matter and the enrichment factors (EF) relative to the Clarke concentrations in the shale are in general determined by the mobility of the chemical elements in the aqueous solution, which is confirmed by the calculated chemical speciation of the elements in the inorganic subsystem of the surface waters of Onezhskii Bay.     

Xenoliths of Eclogites with Diamonds from the Yubileinaya Kimberlite Pipe,Yakutia

The first results of study of minerals and diamonds of diamond-bearing eclogites from kimberlites of the Yubileinaya pipe with a variable percent amount of clinopyroxene and garnet are presented. Samples with a garnet content from 30 to 90% of the xenolith volume are dominant among the round to oval xenoliths with diamonds. Five eclogite samples contain grains of accessory rutile, as well as corundum and kyanite. Some samples host two or more diamond crystals.     

Behavior of heavy metals in sulfide mine tailings and bottom sediment (Salair,Kemerovo region,Russia)

The given work focused on solving the problem of environmental geochemistry related to investigation of element speciation, their mobility, and migration in polluted areas. The purpose was to describe quantitatively migration, distribution, and redistribution of heavy metals by the example of the old tailings (Talmovaya sands) of the Lead Zinc Concentration Plant (Salair, Kemerovo region, Russia) and technogenic bottom sediments of the Malaya Talmovaya river. Contents of elements in the sulfide tailings range in the following limits: Zn: 1,100–27,000 ppm, Cd: 1.3–240 ppm, Pb: 0.01–0.81 ppm, Cu: 220–960 ppm, As: 15–970 ppm, Fe: 19,000–76,000 ppm, and Ba: 80,000–1,00,000 ppm. Element concentrations in the river sediment are proportional to the element contents in the sulfide tailings. Element speciations in the sulfide tailings and technogenic bottom sediments were investigated by the modified sequential extraction procedure. Chemical forms of heavy metals in pore water and surface water were calculated by WATEQ4F software. Principles of heavy metal migration in the sulfide tailings and technogenic bottom deposits were established. The obtained results about element species in the sulfide tailings and sediment explain the main principles of element migration and redeposition. In the mine waste and technogenic bottom deposits, there is vertical substance transformation with formation of geochemical barriers.     

Geochemistry of natural waters – The legacy of V.I. Vernadsky and his students

The geochemist, Vladimir Ivanovich Vernadsky has only recently become recognised internationally, despite being regarded as one of the greatest names in science of the 20th century in his homeland Russia. There are several reasons for his lack of renown in the west, but mainly because his most important work “The Biosphere” was only fully translated into English in 1997. This book and the ideas it contains are now becoming regarded as one of the pioneering works of the last century. It defines the biosphere as a unifying, holistic concept for the earth system at a time when reductionism was the driving motivation in scientific research. Above all, for earth scientists, Vernadsky regarded life as the driving geological force. However another, as yet unpublished work (in three volumes) entitled “The History of Natural Waters” also deserves similar attention. This book explores many concepts in hydrogeology, geochemistry, geofluid circulation and especially biology in which water is described as an integral part of the biosphere.