The massive Carrizozo lava flow, which traveled 75 km down the Tularosa Basin of south-central New Mexico, is one of Earth's longest known Holocene lava flows. The youthful-looking basaltic flow originated from a broad low basaltic shield on the floor of the Tularosa Basin, east of the Rio Grande Rift, topped by Little Black Peak, a small cinder cone. The 4.2 cu km tube-fed pahoehoe flow covered 330 sq km and has a width that ranges from 1 km in the central neck region to 5 km in the proximal and distal portions. The flow was inferred to have been emplaced during a single long-duration eruption estimated to have lasted 2-3 decades. A surface exposure age of about 5200 years Before Present was obtained for the Carrizozo lava flow, the second youngest in New Mexico. An older lava flow traveled 16 km south and 11 km east from Broken Back crater.