Geological Processes of the Lithosphere

Study Notes

Lithosphere: Geological Processes

Plate Tectonics

The lithosphere is broken into several large plates that move relative to each other
These plates are in constant motion, sliding over the more fluid asthenosphere below
Plate boundaries are areas where plates meet and interact, resulting in geological processes such as:
- Divergence (plates moving apart)
- Convergence (plates moving together)
- Transform motion (plates sliding past each other)

Processes at Plate Boundaries

Divergent boundaries:
- Seafloor spreading: new oceanic crust is created as magma rises from the mantle and solidifies
- Continental rifting: a continent is pulled apart, resulting in the formation of a new ocean basin
Convergent boundaries:
- Subduction: one plate is forced beneath another, resulting in earthquakes and volcanic activity
- Continental collision: two plates collide, resulting in mountain building and crustal thickening
Transform boundaries:
- Horizontal motion between two plates, resulting in earthquakes and faulting

Volcanic Activity

Volcanic arcs: chains of volcanoes formed at subduction zones, where the overriding plate is subjected to increasing heat and pressure
Hotspots: volcanic regions where mantle plumes rise to the surface, resulting in volcanic activity (e.g. Hawaii)

Mountain Building

Orogenesis: the process of mountain building through the collision of tectonic plates
Folding: the bending of rocks due to compressional forces
Faulting: the breaking of rocks along fault lines due to tensional or compressional forces

Description

Test your knowledge of the Earth's lithosphere, including plate tectonics, geological processes at plate boundaries, volcanic activity, and mountain building. Learn about the different types of plate boundaries, volcanic arcs, and orogenesis.