Which process often enhances mineral concentration due to tectonic activity?

The correct answer involves subduction, which is a key tectonic process that significantly enhances mineral concentration. During subduction, one tectonic plate is forced under another and into the mantle, creating extreme pressure and temperature conditions. This process can lead to the formation of various minerals as the plates interact.

As the descending oceanic plate is subducted, it can carry sediments rich in minerals down into the mantle. The intense heat and pressure cause those minerals to undergo transformations, often resulting in concentrated deposits. These processes can also lead to the formation of economically valuable minerals, such as gold, copper, and nickel, at subduction zones.

In contrast, while weathering can break down rocks and potentially release minerals, it typically does not concentrate them. Metamorphism can also change the structure and composition of existing rocks but often does not lead to the concentration of new minerals in the same context as subduction. Exhumation refers to the process of bringing rocks from depth to the surface, which may expose mineral deposits but does not inherently enhance their concentration due to tectonic activity like subduction does.