. . . . "volcanic" . . . . . . . . . . . . . . . . . "plugs" . . . . . . . "volcanic remnant" . . . . . . . . "column" . . "mouth of an extinct volcano" . "volcanic necks" . . . "plug" . . . . "neck" . . "plugged" . . "block" . . . . . . . . . . "volcanic neck" . . . . "Volcanic plug" . . . . . . . . "Volcanic plug" . . "erosional remnant" . . . . . . . . . . . . . . . . . . . . "necks" . . . . . . . . . . . . . . "Volcanic neck" . "lava plug" . . . . . . . . . . . . . . "plugging" . . "volcanic plug" . . . . . .