Tectonic Plate Boundaries
Earth is unique among all known terrestrial planets in having plate tectonics. By constantly bringing new mantle material to the surface, plate tectonics affects the chemistry of the ocean and atmosphere, and thus also the long-term climate stability and the biological evolution. Understanding plate tectonics is thus a fundamental step towards understanding the Earth system as a whole. How do tectonic plate boundaries form and evolve through geological time? How do subduction zones form? How did billions of years of Earth’s tectonic evolution affect the mechanical properties of its plate boundaries today? These are some of the most pressing questions addressed by the geoscientists today.
Mantle Convection
Mantle convection, which occurs by solid-state creep of its rocks, is the dominant way by which the Earth cools. The flow of the mantle is the driving force for all geological activity on our planet: formation of continents, plate tectonics, mountain building, volcanism, earthquakes, etc. The flow of the mantle has changed through the Earth’s history, and understanding the mechanical and thermal processes involved in it would shed light on the entire planet’s evolution, including the cycle of materials such as water and carbon between its surface and deep interior.