View Full Version : hydrothermal vents

solomon levi
03-29-2011, 07:36 PM

04-22-2013, 02:14 PM
I like this old video/thread. Here's some new info for it :)

White and others (1988) extensively drilled and cored Norris, Lower, and Upper Geyser Basins. They determined water-chemistry changes with depth, and they associated mineral-alteration species with water chemistry. They identified four types of water. Type-1 water is of neutral pH and is chloride-silica rich; it has altered the mafic minerals in rhyolite country rock to goethite, hematite, and chalcedony and has changed plagioclase to siliceous sinter and montmorillonite. Type-2 water is formed from vapor-dominant gas and has less chloride than the other water types. Near the surface, type-2 water is acidified by oxidation of hydrogen sulfide; it is then recirculated and reheated within 100 ft of the surface. Type-2 water bleaches the surrounding country rock, leaches ferric oxides, and creates montmorillonite, illite, and chlorite. Type-3 water is acid-chloride-sulfate rich and is generated by restricted flow of neutral pH, chloride-silica-rich water that combines with sulfur and rain and snowmelt surface water. Type-3 water bleaches the countray rock, leaching all ferric oxides. Type-4 water is acid-sulfate rich, low in chloride, and is generated above boiling water table where steam combines with hydrogen sulfide gas to yield restricted, hot, low-pH water. Type-4 water bleaches the country rock, leaches ferric oxides, and alters potassium feldspar and sanidine to kaolinite, opal, and cristobalite. Type-4 water forms mixed-layer clay minerals -- montmorillonite is dominant at temperatures lower than 198 C; mixed-layer montmorillonite-illite is dominant between 198 and 238 C; and illite is dominant at temperatures higher than 238 C(White and others, 1988)

taken from: Hydrothermally Altered Rock and Hot-spring Deposits at Yellowstone National Park. (pubs.usgs.gov/pp/1717/downloads/pdf/p1717O.pdf)
In my opinion a very interesting report.

04-23-2013, 06:37 PM
I have been thinking on this more.

The above article mentions that deep below the surface magma-heated water turns to vapor, but as it can't escape due to pressure and container (all the Earth covering it), the vapor congeals and remains liquid. Eventually this finds exit in hot springs and vents, but as the pressure subsides, it condenses into normal water -- or apparently in Yellowstone, one of four types based on mineral composition and pH.

sounds a lot like an 'aqueous vapour' to me ;)