stylistic:tone, information:extraction
Complex dunes

Complex dunes (star dunes or rhourd dunes) are characterized by having more than two slip faces. They are typically 500 to 1,000 meters (1,600 to 3,300 ft) across and 50 to 300 meters (160 to 980 ft) high. They consist of a central peak with radiating crests and are thought to form where strong winds can come from any direction. Those in Gran Desierto de Altar of Mexico are thought to have formed from precursor linear dunes due to a change in the wind pattern about 3000 years ago. Complex dunes show Little lateral growth but strong vertical growth and are important sand sinks.