Kirby Runyon points at the wall of Kilbourne Hole

Kirby Runyon points at the wall of Kilbourne Hole
Kirby Runyon points at the wall of Kilbourne Hole Planetary geologist Kirby Runyon points at the wall of Kilbourne Hole, a maar volcanic crater in New Mexico, USA. Kilbourne Hole is well known for its unique geological structure, formed by explosive steam eruptions when rising magma encountered groundwater. Mat Kaplan