mercury mineralization has occurred in relation with a listwaenitic type hydrothermal alteration system in tavreh area located northwest of khoy. mercury-bearing alteration zone which has an area about 0.4 km2 is situated in one of aland river upstreams. the only mercury compound found in this district is mercury sulfide (cinnabar) deposited as vein and veinlet forms. geochemical investigations...

introduction agates are presumed as a kind of precious stone that could be formed in magmatic, metamorphic and even sedimentary environment. mechanism for agate formation is not clear and is produced in laboratories. some hot springs and geothermal activity or white chimneys in the ocean floor, have some deposits like chalcedony but never produce agate. agate formation temperature varies betwee...

When its hydrothermal supply ceases, hydrothermal sulfide chimneys become inactive and commonly experience oxidative weathering on the seafloor. However, little is known about the oxidative weathering of inactive sulfide chimneys, nor about associated microbial community structures and their succession during this weathering process. In this work, an inactive sulfide chimney and a young chimney...

Abstract Magnetic surveys are used to identify and monitor hydrothermally altered regions on volcanoes. Commonly such magnetic data interpreted the premise that hydrothermal alteration consumes Fe‐Ti oxides in host rocks, reducing their total magnetization. Here, we report a contrasting observation from Whakaari (White Island) volcano New Zealand. We study properties of 42 conduit‐filling surfi...

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...