Arizona Volcanoes

For those who have a burning desire to know how geology works



North America 65 million years ago. For millions of years the North American techtonic plate pushed westward from Europe until it collided with the Eurasia plate.

Plate techtonics below the shallow sea lofted the land upward a mile, and that drained the inland sea into the Gulf of Mexico.

27 million years ago these overlapping plates spawned the first volcanoe in Arizona near the town of Williams.

This trend continued in an eastern direction until 6 million years ago when newer volcanoes broke through the surface. 

30 thousand years ago the youngest volcanoes emerged to further alter the landscape.

As volcanic activity wained, the Arizona land was an elevated and arid high plains landscape and erosion took over to form the landscape we know today.

This map marks the first volcanoes with the color brown. These volcanic fields  stretched from Mexico to where Denver, Colorado now stands.

Mauve areas mark younger lava beds on top of where the mesas and monuments stand today.

Areas between the high places were soft and more easily eroded to current level of altitude.

More about all of that.

To summarize, the first volcano emerged near Williams, Arizona, and the last one was Sunset Crater.

Sunset crater last errupted 11 hundred years ago.

That one buried several Indian villages with casualties unknown.

Spanning a distance of fifty miles, these craters have sprang up in a direction of west to east.

In the future, chances are that another volcano will emerge east of Flagstaff.   

More Information:

volcanoe1, volcanoe2, volcanoe3.

Potted Histories TM 1990 by donkelly.

Histories For Kids TM 1998 by donkelly

All rights reserved 1990- Present