The Taos Plateau volcanic field is an area of extensive volcanism in Taos County, New Mexico, United States. It is the largest volcanic field in the Rio Grande Rift, spreading over 7,000 square kilometers (2,700 sq mi). The total erupted volume is estimated at 420 cubic kilometers (100 cu mi). The age of most of the vents and associated lava flows in the field is estimated to be between 1.8 and 4 million years, with a few 22-million-year-old vents. The composition of the lavas varies from tholeiitic basalt to rhyolite. Landforms include sheet flows, cinder cones, and shield volcanoes. The sheet flows of the Servilleta Basalt are well-exposed in the Rio Grande Gorge carved by the Rio Grande. The highest point of the field is San Antonio Mountain at 10,908 feet (3,325 m).