Hydrothermal alteration and fluid pH in alkaline-hosted epithermal systems

Lithological and Hydrothermal Alteration Mapping of Epithermal, Porphyry and Tourmaline Breccia Districts in the Argentine Andes Using ASTER Imagery

The area of interest is located on the eastern flank of the Andean Cordillera, San Juan province, Argentina. The 3600 km2 area is characterized by Siluro-Devonian to Neogene sedimentary and igneous rocks and unconsolidated Quaternary sediments. Epithermal, porphyry-related, and magmatic-hydrothermal breccia-hosted ore deposits, common in this part of the Frontal Cordillera, are associated with ...

Eocene Hydrothermal Systems and Contrasting Hydrothermal Alteration in the Battle Mountain District, Nevada

Hydrothermal Fluid Flow and Mineral Alteration in a Fractured Rock under Multiphase

The geochemical evolution of hydrothermal fractured rock systems occurs through a complex interplay of multi-phase fluid and heat flow, and chemical transport processes. On the basis of previous work we present simulations of reactive hydrothermal flow that include (1) detailed fracture-matrix interaction for fluid, heat and chemical constituents, (2) gas phase participation in multiphase fluid...

Sulfur Metabolizing Microbes Dominate Microbial Communities in Andesite-Hosted Shallow-Sea Hydrothermal Systems

To determine microbial community composition, community spatial structure and possible key microbial processes in the shallow-sea hydrothermal vent systems off NE Taiwan's coast, we examined the bacterial and archaeal communities of four samples collected from the water column extending over a redoxocline gradient of a yellow and four from a white hydrothermal vent. Ribosomal tag pyrosequencing...

Geochemical and Visual Indicators of Hydrothermal Fluid Flow through a Sediment-Hosted Volcanic Ridge in the Central Bransfield Basin (Antarctica)

In the austral summer of 2011 we undertook an investigation of three volcanic highs in the Central Bransfield Basin, Antarctica, in search of hydrothermal activity and associated fauna to assess changes since previous surveys and to evaluate the extent of hydrothermalism in this basin. At Hook Ridge, a submarine volcanic edifice at the eastern end of the basin, anomalies in water column redox p...