Earthquakes can cause flash deposition of minerals, says study

Nature : Veins of gold and other minerals may form in quartz and granite almost instantaneously when water under high pressure suddenly vaporizes during an earthquake, according to a study published yesterday in Nature Geoscience. When an earthquake occurs, fault lines slip, and sideways zigzag cracks connecting the faults open up. That opening up of so-called fault jogs causes the air pressure to drop precipitously and the hot, mineral-laden water flowing through them to vaporize. Any minerals or metals in the solution then get deposited on the surrounding rock. Although each single earthquake may produce only one tiny gold vein, any given fault system can produce hundreds of thousands of small earthquakes each year and, over time, very large quantities of gold. Besides merely pointing prospectors to new gold deposits, however, the study could have more scientific value by providing seismologists with new data to help improve earthquake forecasting.