Volatile element signatures in the mantles of Earth,Moon, and Mars: Core formation fingerprints from Bi,Cd, In,and Sn

Volatile element concentrations in planets are controlled by many factors such as precursor material composition, core formation, differentiation, magma ocean and magmatic degassing, and late accretionary processes. To better constrain the role of core formation, we report new experiments defining the effect of temperature, and metallic S and C content on the metal-silicate partition coefficient (or D(i) metal/silicate) of the volatile siderophile elements (VSE) Bi, Cd, In, and Sn. Additionally, the effect of pressure on metal-silicate partitioning between 1 and 3 GPa, and olivine-melt partitioning at 1 GPa have been studied for Bi, Cd, In, Sn, As, Sb, and Ge. Temperature clearly causes a decrease in D(i) metal/silicate for all elements. Sulfur and C have a large influence on activity coefficients in metallic Fe liquids, with C causing a decrease in D(i) metal/silicate, and S causing an increase. Pressure has only a small effect on D(Cd), D(In), and D(Ge) metal/silicate. Depletions of Bi, Cd, In, and Sn in the terrestrial and Martian mantles are consistent with high PT core formation and metal-silicate equilibrium at the high temperatures indicated by previous studies. A late Hadean matte would influence Bi the most, due to its high D(sulfide/silicate) ~2000, but segregation of a matte would only reduce the mantle Bi content by 50%; all other less chalcophile elements (e.g., Sn, In, and Cd) would be minimally affected. The lunar depletions of highly VSE require a combination of core formation and an additional depletion mechanism—most likely the Moon-forming giant impact, or lunar magma ocean degassing.     

First data on chemical composition of zircon from lithium-fluorine granite of the Severnyi pluton, Chukchi Peninsula

The chemical composition of zircons from lithium-fluorine granite of the Severny pluton in the Chaun region, Chukchi Peninsula, has been studied. The magmatic origin of zircons has been established. Elevated LREE, Li, and Nb contents; moderate enrichment in Hf; and deep Eu anomalies are characteristic of zircons from rare-metal granite. The contents and distribution of chemical elements in studied zircons differ from those of biotite granite. Zircons from lithium-fluorine granite of the Severny pluton also differ from the worldwide analogs in moderate Hf, Y, and REE concentrations and extremely low contents of U, Th, and other incompatible elements.     

Composition and evolution of accessory mineralization of Li–F granites in the Far East as indicators of their ore potential

The ore potential of Pacific Li–F granites is considered on the basis of original and published data on composition of these granites and related metasomatic rocks in the Badzhal (Amur region) and Kuiviveem–Pyrkakai (Chukchi Peninsula) ore districts. The accessory mineralization in rare-metal granites is compared with that in W–Sn deposits. The main features in evolution of magmatic and hydrothermal mineralization are pointed out. A conclusion on the similarity between mineralization of the zwitter–tourmalinite type and accessory minerals in Li–F granites is drawn. It is established that magmatic and hydrothermal types of mineralization belong to the same evolutionary sequence. Genetic links between Li–F granites and the large ore deposits in the East Asian tungsten–tin zone are suggested.     

Granite Systems with Rare-Metal Pegmatites

Geology of Ore Deposits - For most rare-metal pegmatite fields, two generations of granitic pegmatites are documented, namely, beryll-bearing (often with tantaloniobates and muscovite, which are...     

The East Caledonian Current: A Case Example for the Intercomparison between AltiKa and In Situ Measurements in a Boundary Current

This paper presents an assessment of SARAL/AltiKa satellite altimeter for the monitoring of a tropical western boundary current in the south-western Pacific Ocean: the East Caledonian Current. We compare surface geostrophic current estimates obtained from two versions of AltiKa along-track sea level height (AVISO 1 Hz and PEACHI 40 Hz) with two kinds of dedicated in situ datasets harvested along the satellite ground tracks: one deep-ocean current-meter mooring deployed in the core of the boundary current and five glider transects. It is concluded that the AltiKa-derived current successfully captures the velocity of the boundary current, with a standard error of 11 cm/s with respect to the in situ data. It also appears important to reference AltiKa sea level anomaly to the latest mean dynamic topography available in our area. Doing so, Ka-band altimetry provides a satisfactory representation of the western boundary current. Thereby, it usefully contributes to observing its variability in such a remote and under-observed ocean region. However, the rather long repeat period of SARAL (35 days) in comparison to the high frequency variability seen in the flow velocity of the boundary current calls for a combined use of SARAL with the other satellite altimetry missions.     

Ferrokësterite and Kësterite in Greisens Associated with Lithium–Fluorine Granites of the Russian Far East

Geology of Ore Deposits - The typomorphic features and origin of the ferrokësterite and kësterite sulfostannates from Li–F granite-related greisen ore deposits of the Russian Far...     

Wolframoixiolite and niobian ferberite from zinnwaldite granitic rocks of the Chukchi Peninsula

The finding of wolframoixiolite with inclusions of niobian ferberite is described from zinnwaldite granite and ongonite of the Severny pluton of the Chukchi Peninsula. The optical, morphological, and chemical properties of minerals are characterized and compared with their analogues from other regions. The petrologic and mineragenic index implications of the minerals are discussed with allowance for our contemporary mineralogical knowledge on W-bearing Ta-Nb minerals.     

Structural and chemical heterogeneity of natural crystals and microgeochemical line of research in ontogeny of minerals

A review of the current state of genetic mineralogy in the field of the chemical heterogeneity of mineral individuals is presented. Due to advances in the local analysis of matter, the ontogenetic approach is now being focused on the chemical anatomy of minerals. A new line of research, microgeochemistry, deals with the migration of chemical elements in natural crystals caused by defects in the crystal lattice. It becomes evident that structural and chemical heterogeneity is an intrinsic property of mineral individuals. Phenomenological laws of this heterogeneity and the interaction of atoms with lattice defects are stated.     

Lethal and estrogenic effects of 4-nonylphenol in the cockle Cerastoderma glaucum

The lethal and sublethal effects of the xenoestrogen 4-nonylphenol (NP) were evaluated in the cockle Cerastoderma glaucum. In a 96-h lethality test, bivalves were exposed to 0, 0+ acetone, 0.19, 0.38, 0.75, 1.5 and 3.0 mg NP/l. The 96-h LC(50) value was 0.3mg NP/l. No mortality was observed at 0.1 mg NP/l. The potential estrogenicity of NP was studied in both sexually undifferentiated (resting phase) and differentiated (pre-spawning phase) cockles, exposed for 7 and 14 days to 0, 0+ acetone, 0.0125, 0.025, 0.05, and 0.1 mg NP/l. Vitellogenin (Vg)-like protein levels were determined in both haemolymph and digestive gland by the alkali-labile phosphate (ALP) assay. In the resting phase, exposure for 7 days to 0.1 mg NP/l resulted in significant increases in ALP in both haemolymph and digestive gland, compared with controls. A significant increase was also observed in digestive gland of animals exposed to 0.0125 mg NP/l-exposed animals. After 14 days of exposure, haemolymph ALP levels were significantly increased in exposed animals at all NP concentrations tested, whereas no difference was recorded in digestive gland. In the pre-spawning phase, exposure for 7 days to NP significantly increased ALP levels in haemolymph from males exposed at all NP concentrations tested, whereas no significant variations were found in haemolymph from females. NP (0.05 and 0.1 mg/l) was also shown to increase ALP concentrations significantly in digestive gland of males, but not in those of females. Likewise, after 14 days' exposure, ALP levels significantly increased in haemolymph from males only at 0.1 mg NP/l. Conversely, NP caused significant increases in ALP levels in digestive gland from both males (at all NP concentrations tested) and females (at 0.025 and 0.1 mg NP/l). These results demonstrate that NP induces Vg synthesis in C. glaucum. Interestingly, males were more responsive to NP than females.