What is low sulfidation?
What is low sulfidation?
In low sulfidation the main control for Gold deposition, is fluid boiling – caused by a drop in the confining pressures the fluid approaches the surface. Unlike the muddy acid waters of high sulfidation systems, the low sulfidation fluids are usually crystal clear and have a neutral to slightly alkaline pH.
What is high sulfidation?
The term high-sulfidation (HS) (Hedenquist 1987) is now widely used; the term was proposed originally to refer to a fundamental genetic aspect, the relatively oxidized state of sulfur contained in the hydrothermal system (i.e., initially SO2-rich).
What is vuggy silica?
Vuggy silica developed below the water table as rising magmatic vapors condensed and generated acidic fluids that leached feldspar and mafic minerals out of the rock leaving only a dense residual quartz matrix surrounding empty phenocryst sites.
What are epithermal neutrons?
a neutron having an energy in the range immediately above the thermal range, that is, having an energy between a few hundredths and approximately 100 ev.
What is an epithermal vein?
Epithermal veins are the dominant structurally controlled style of mineralization. Veins mark faults and other open fractures through which hydrothermal fluids flowed and precipitated hydrothermal phases, most commonly quartz or other silica phases and carbonate minerals.
What are some examples of hydrothermal ore deposits?
Background
| Hydrothermal deposit Subcategory | Known abbreviation | Principal metals |
|---|---|---|
| Porphyry | — | Cu, Mo, Au |
| Skarn | — | Cu, Mo, Ag, Au |
| Volcanogenic massive sulphide | VMS | Cu, Zn, Pb |
| Sedimentary exhalative | SEDEX | Zn, Pb |
What is epithermal gold?
➢ Epithermal Gold refers to a type of gold deposit formed from hydrothermal fluids. at shallow levels in the earth’s crust. “Epithermal” is an old term used to classify. hydrothermal deposits based on temperature and depth of deposition.