In the 1940s and 1950s, geologists conducted a groundbreaking studyon the formation and growth of the Paricutin volcano near San Juan,Mexico. The volcano originated as a small crack emitting steam with avolcanic sulfur odor, leading to a series of explosions starting onFebruary 20, 1943. Paricutin rapidly grew to a height of 1,391 feet (424meters) within a year, covering nearby villages and farmland with lavaand ash during its eruption.