A worker digs for gold in a pit in Qingmuchuan, northwest China. Photo: EPA

Quakes can lead to build-up of gold deposits in earth's crust, study says

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 Australian researchers. 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 the journal.