The oval Brandberg structure, a large intrusive igneous formation in west-central Namibia, approximately 45 miles (70 kilometers) from the Atlantic Ocean, has an average diameter of approximately 15 miles (25 kilometers) and an elevation of 8445 feet (2575 meters) above sea level. Bordering the structure on the west is a thin strip of the Namib Desert, and bordering on the east is an extensive plateau (reddish-brown area) that appears also to be volcanic in origin, as does the darker area to the north-northwest, across which the westward-flowing Ugab River can be traced easily. The tans and brownish-yellows show a variety of sandy surfaces. Tin and tungsten are mined in this region of Namibia.