<P> Mount Taylor was active from 3.3 to 1.5 million years ago during the Pliocene , and is surrounded by a field of smaller inactive volcanoes . Repeated eruptions built lava domes and produced lava flows , ash plumes , and mudflows . The mountain is surrounded by a great volume of volcanic debris , suggesting multiple major eruptions , possibly similar to that of Mount Saint Helens and the San Francisco Peaks near Flagstaff , Arizona . Estimates vary about how high the mountain was at its highest . Conservative estimates place its maximum near a similar pre-explosion height for the San Francisco Peaks of 16,000 to 18,000 feet ( 4,900 to 5,500 m ) , and an extreme estimate places it near 25,000 feet ( 7,600 m ) . </P>
<P> Mount Taylor was active from 3.3 to 1.5 million years ago during the Pliocene , and is surrounded by a field of smaller inactive volcanoes . Repeated eruptions built lava domes and produced lava flows , ash plumes , and mudflows . The mountain is surrounded by a great volume of volcanic debris , suggesting multiple major eruptions , possibly similar to that of Mount Saint Helens and the San Francisco Peaks near Flagstaff , Arizona . Estimates vary about how high the mountain was at its highest . Conservative estimates place its maximum near a similar pre-explosion height for the San Francisco Peaks of 16,000 to 18,000 feet ( 4,900 to 5,500 m ) , and an extreme estimate places it near 25,000 feet ( 7,600 m ) . </P>
when was the last time mt taylor erupted
when was the last time mt taylor erupted
1.5 million years ago
1.5 million years ago