Swiss geologists have simulated the formation process of the most productive porphyry copper deposits and discovered that groundwater plays a crucial role. Copper is one of the most valuable metals for the global economy, with over 16 million tons of copper being extracted worldwide annually. As demand for copper continues to rise, Swiss geologists hope to discover new large copper deposits by simulating the formation of economically interesting porphyry copper deposits. Chile currently offers the most significant copper deposit, with a mining rate of around 5.5 million tons of copper. However, new deposits must be developed in the long term to meet the demand on the world market.
In a recent article published in the journal Science, the geologists reported that rising magmatic gases were cooled over thousands of years, resulting in copper being deposited in the earth’s crust in an economically interesting concentration of one to three percent. Huge magma chambers responsible for the formation of copper deposits are located in the upper crust of the earth. Weis and his colleagues simulated the physical and chemical processes in the magma chambers using a computer model. Extremely hot metal-bearing magmatic gases rose from the crystallizing magma chambers and were cooled down to about 400 degrees Celsius by groundwater many kilometers above the earth’s crust. This process allowed for a high concentration of copper to crystallize.
Although the richest copper deposits in the world are found in the United States, Chile, Indonesia, and Peru, the geologists believe that there could be many more such deposits. The geological conditions for the formation of such copper deposits are present in many parts of the world. However, the simulations show that it will be necessary to dig much deeper into the earth’s crust to access new copper sources in the future. Whether this effort is worthwhile will depend on the copper price, which is currently around 6,000 euros per ton.
