Pinacate Peaks and Gran Desierto de Altar, Mexico31.7N 113.5W
The Pinacate Peaks (Sierra Pinacate), identifiable as a dark brown area in the lower left quadrant, are a volcanic group of volcanic peaks and cinder cones. They are located mostly in the Mexican state of Sonora along the international border adjacent to the U.S. state of Arizona, surrounded by the vast sand dune field of the Gran Desierto de Altar.
The tallest of the peaks is Cerro del Pinacate (also called Volcán Santa Clara), elevation 3,904 feet (1,190 m). The volcanoes here have erupted here sporadically since about 4 million years ago, probably in association with the opening of the Gulf of California. The most recent volcanic activity was about 11,000 years ago.