The hydrothermal mats, mounds, and chimneys of the southern Guaymas Basin are the surface expression of complex subsurface hydrothermal circulation patterns. In this overview, we document the most frequently visited features of this hydrothermal area with photographs, temperature measurements, and selected geochemical data; many of these distinct habitats await characterization of their microbi...

The plutonic complex in SE Jersey consists of a late Precambrian gabbro-diorite mass which has been intruded by several granites. The status of the diorites which, like the gabbros, often possess a layered structure, is not clear. New geochemical data, including rare earth and trace element analyses, suggest that acid-basic magma mixing was not responsible for the variety of intermediate rocks....

In gold (Au) exploration, the analysis of both bulk leach extractable (BLEG) and acid-extractable Au in <180μm stream sediment fraction are two most common approaches. The Eskişehir- Sivrihisar region Western Türkiye hosts several orogenic type mineral deposits. purpose this study is to delineate geochemical anomalies ore-related elements track their dispersion, which may lead discovery unknown...

There is particular concern in Western Europe about the environmental problems, and urgent and concerted international action is warranted. An evaluation of the present state of pollution requires systematic, compatible data on the present distribution as well as the preindustrial, natural distribution of chemical elements in surface environments. The appliance of overbank sediments from river ...

Geochemical heterogeneities may cause spatial variations in virus inactivation rates resulting from interactions with minerals leading to differences in natural disinfection capacity within an aquifer. Column studies investigating the interaction of the bacteriophage H40/1 with natural sands sampled from the Kappelen test site (Kappelen), Bern, Switzerland indicated that inactivation rates are ...

The absence of dunite (>90 vol% olivine) in the howardite, eucrite, and diogenite (HED) meteorite suite, when viewed with respect to spectroscopic and petrologic evidence for olivine on Vesta, is problematic. Herein, we present petrologic, geochemical, and isotopic evidence confirming that Miller Range (MIL) 03443, containing 91 vol% olivine, should be classified with the HED clan rather than w...

Introduction: Major ambiguities remain in our current understanding of the geochemical evolution of the moon. That situation arises partly because (a) our geochemical and isotopic data sets for mare basalts are overly influenced by samples from the Procellarum KREEP Terrain (PKT [1]), and (b) samples of the highland crust useful for isotopic studies are limited in both quantity and quality. Fut...

The production of hydrogen and methane by geochemical reactions associated with the serpentinization of ultramafic rocks can potentially support subsurface microbial ecosystems independent of the photosynthetic biosphere. Methanogenic and methanotrophic microorganisms are abundant in marine hydrothermal systems heavily influenced by serpentinization, but evidence for methane-cycling archaea and...

Although the accelerated transport of Tc, Cs, and U within the vadose zone beneath the 200-West Area of the Hanford tank-farm area has been recognized, the mechanisms responsible for the vertical migration of the radionuclides is unclear. Does horizontal stratification enchance the lateral movement of contaminants, which in turn enhances vertical perferential flow due to perched water dynamics?...

A geochemical modeling of gold deposition was performed using the EQ3/EQ6 software package using conditions inferred from geological, petrographic, geochemical and fluid inclusion data from the Bloco do Butiá gold mine, Lavras do Sul, RS. Gold in the mine occurs only in the pyrite structure (invisible gold). The pyrite occurs associated with white mica (phengite) in the zone of phyllic alterati...