Tall ‘hornito-style’ lava stalagmites and lava column in lava column cave, El Malpais National Monument
— Victor J. Polyak and Paula P. Provencio

New Mexico hosts spectacular lava tube caves that exhibit remarkable lava features. Most of these caves are in El Malpais National Monument. Two types of lava features, lava columns and lava stalagmites, are named for their resemblance to columns and stalagmites common to limestone caves. Lava Column Cave, in El Malpais National Monument, exhibits rare large examples of a lava column and two lava stalagmites. We measured one of the lava stalagmites and the lava column heights to be 3.17 meters (10.4 feet) and 4.45 meters (14.6 feet), respectively, making them among the largest thus far reported in El Malpais National Monument. We also observed that these lava features have central conduits. We suggest they formed the same way that hornitos and squeeze-ups form on lava flow surfaces, by lava extruding from the floor of the cave, rather than from accumulation of dribbles and blobs of lava falling from the ceiling. Our interpretation for the origin of these lava features differs from the origin of the more typical lava stalagmites and columns.