Where to Find Gold – Look to Ancient Volcanic Zones

The following is some more evidence of the geology that helps to produce gold deposits. We are dedicated to help people prospect and find gold. Join our membership area that will provide software tools, instuctional support, and tutorials on how to look for and profitably prospect areas.

From: Kious and Tilling, 1996, This Dynamic Earth: The Story of Plate
Tectonics: USGS General Interest Publication

Most of the metallic minerals mined in the world, such as copper, gold, silver, lead, and zinc, are associated with magmas found deep within the roots of extinct volcanoes located above subduction zones. Rising magma does not always reach the surface to erupt; instead it may slowly cool and harden beneath the volcano to form a wide variety of crystalline rocks (generally called plutonic or granitic rocks). Some of the best examples of such deep-seated granitic rocks, later exposed by erosion, are magnificently displayed in California’s Yosemite National Park. Ore deposits commonly form around the magma bodies that feed volcanoes because there is a ready supply of heat, which convectively moves and circulates ore-bearing fluids. The metals, originally scattered in trace amounts in magma or surrounding solid rocks, become concentrated by circulating hot fluids and can be redeposited, under favorable temperature and pressure conditions, to form rich mineral veins.  
The active volcanic vents along the spreading mid-ocean ridges create ideal environments for the circulation of fluids rich in minerals and for ore
deposition. Water as hot as 380 degrees C gushes out of geothermal springs along the spreading centers. The water has been heated during circulation by contact with the hot volcanic rocks forming the ridge. Deep-sea hot springs containing an abundance of dark-colored ore minerals (sulfides) of iron,
copper, zinc, nickel, and other metals are called “black smokers.” On rare occasions, such deep-sea ore deposits are later exposed in
remnants of ancient oceanic crust that have been scraped off and left (“beached”) on top of continental crust during past subduction processes. The
Troodos Massif on the Island of Cyprus is perhaps the best known example of such ancient oceanic crust. Cyprus was an important source of copper in the ancient world, and Romans called copper the “Cyprian metal”; the Latin word for copper is cyprium.

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