According to a new study, water in faults vaporises during an earthquake, depositing gold. A model published in the journal Nature Geoscience is said to provide a quantitative mechanism for the link between gold and quartz seen in many of the world's gold deposits. When an earthquake strikes, it moves along a rupture in the ground — a fracture called a fault. Big faults can have many small fractures along their length, connected by jogs that appear as rectangular voids. Water often lubricates faults, filling in fractures and jogs.