Tectonics is the scientific study of the deformation of the rocks that make up the Earth’s crust and the forces that produce such deformation. It deals with the folding and faulting associated with mountain building; the large-scale, gradual upward and downward movements of the crust, and sudden horizontal displacements along faults. Other phenomena studied include igneous processes and metamorphism. Tectonics provides a framework to understand the earthquake and volcanic belts which directly affect much of the global population. Tectonic studies are important for understanding erosion patterns in geomorphology and as guides for the economic geologist searching for petroleum and metallic ores.