hey, i just came across this thread and in regards to the member who mentioned fracking being the cause of earthquakes, i came across this article
yesterday which may or may not be relevant, but i think it is entirely plausible that this is why they are fracking so much.
Solid gold can be deposited in Earth's crust "almost instantaneously" during earthquakes, said a study published in the journal Nature Geoscience on
The gold is formed when a tremor splits open a fluid-filled cavity in the Earth's crust, causing a sudden drop in pressure, according to a team of
This, in turn, causes the fluid to expand rapidly and evaporate, and any gold particles that had been dissolved in it to "precipitate almost
immediately", said a Nature press release.
"Repeated earthquakes could therefore lead to the build up of economic-grade gold deposits."
The researchers said much of the world's known gold was derived from quartz veins that were formed during geological periods of mountain building as
long as three billion years ago.
The veins formed during earthquakes, but the magnitude of pressure fluctuations or how they drove gold mineralisation were not known.
For this study, researchers used a numerical model to simulate the drop in pressure experienced in a fluid-filled fault cavity during an earthquake.
In so doing, they answered a long-standing question about the world's gold resources - how the metal becomes so concentrated from a highly dissolved
state to a solid, mineable one.
The study said single tremors would not generate economically viable gold deposits, which were built up one thin coating at a time.
To form a 100 tonne gold vein deposit would take less than 100,000 years, the team wrote.
edit on 20-3-2013 by rokkiroo because: link was not allowed