Sunset Crater Volcano was born in a series powerful explosions sometime between 1040 and 1100 AD. These eruptions profoundly affected the lives of local people and forever changed the landscape and ecology of the area. The eruption destroyed all plants within a five-mile radius. A fountain of fire, 850 feet high, was visible for miles around. An ash cloud rose 2 1/2 miles into the sky and falling ash covered about 64,000 acres. Sunset Crater is the most recent in a six-million year history of volcanic activity in the Flagstaff, Arizona, area. The people living just northeast of what is now Flagstaff, Arizona, must have been warned by tremors before debris exploded from the ground and rained down on their homes. The lave flows and erupting cinders that followed forced these farmers to leave the rocky lands they had cultivated for over 400 years. This cinder cone reminds us of the powerful forces that shape the Earth - forces that have created more than 600 hills and mountains in the San Francisco volcanic field. These mountains have in turn affected the climate and habitat for all things living in this region. What is now a 1000-foot high volcano began to form when molten rock sprayed high into the air from a crack in the ground, solidified, then fell to Earth as large bombs or smaller cinders. As periodic eruptions continued, the heavier debris accumulated around the vent. The lightest, smallest particles were carried the farthest by wind, dusting 800 square miles of Arizona with ash. Perhaps as spectacular as the original eruption were two lava flows - the Kana-a and the Bonito. They destroyed every living thing in their paths. The entire event may have lasted six months to a year. In a final burst of activity, red and yellow oxidized cinders shot out of the vent and fell onto the rim. The colorful glow of these cinders reminded people of a sunset and led to the volcano's name. The lava flows and cinders still look as fresh and rugged today as the day they were formed.
Painted Desert in the distance.