VolcanismNew Mexico's landscape exhibits all of the known forms of volcanism, from lava flows to mega-eruptions that covered large parts of the Southwest in layers of ash. Four major volcano fields, including the one west of Albuquerque, include cinder cones and marl volcanoes; noted lava flows include the McCarty's Flow (deposited 3,000 years ago) and the Carrizozo Malpais. The Valles Caldera is one of the largest such calderas on the planet, and landscape features such as Frijoles Canyon, the Tent Rocks, and City of Rocks are formed from thick deposits of volcanic ash. Landmark Mt. Taylor is a composite volcano. Capulin Volcano in northeastern NM was designated a National Monument in 1916 and attracts thousands of visitors annually. As much of the volcanism is fueled by stresses along the active expansion zone of the Rio Grande Rift, volcanic activity in New Mexico is considered dormant rather than extinct.