What is a graben?

A graben is a geological feature formed by the downward displacement of a block of the Earth's crust between two fault lines, resulting in a valley. This process occurs due to tectonic forces that pull the crust apart, causing the land on either side to rise. Grabens are often characterized by steep sides and can be found in regions experiencing extensional tectonics, such as rift zones. Common examples include the East African Rift and the Basin and Range Province in the United States.