Some Volcanoes are Simply Asleep for the Moment!

Sunset Crater near Flagstaff is only 932 years old, it has  barely fallen asleep in geologic time. 

And though only a relatively  small volcano when it erupted,  there were First Nations Sinagua Tribes living around the  San Francisco Mountains close by.  So humans experienced this event!

Sunset Crater Volcano National Monument contains the results of much  igneous activity - several colorful cinder cones formed by extinct  volcanoes, and large expanses of lava and ash, mostly unobscured by  vegetation and still pure black in color.   

The dominant peak is Sunset Crater; as with the other cones its  slopes have distinctive dusky red-brown patches formed by oxidised iron  and sulphur, which caused John Wesley Powell, who was the first  modern-day explorer of the area in 1887, to name the mountain 'Sunset  Peak'.  

The contrasting colors of the cinders provide the most unusual  aspect of the national monument but the jagged and twisted lava fields  are also quite spectacular.  Sunset and the neighboring craters are just one small part of the San  Francisco volcanic field, an extensive region of nearly 2,000 square  miles that contains some 600 identified volcanoes. (Research Source) 

The volcanic eruption produced a blanket of ash and lapilli covering  an area of more than 2,100 square kilometers (810 sq mi) and forced the  temporary abandonment of settlements of the local Sinagua. (Research Source)   

I am flying to the north of the Sunset Crater National Monument when I  lensed this image. In the immediate foreground lies the Bonita Lava  Flow.  This is lava that broke out the side of the cinder cone  formed  structurally  complex flows some nearly two miles in length composed of   basalt.  

Flows typically start as pahoehoe,  thin and runny, forming a  smooth  ropy texture when cooled. As the lava cools and becomes thicker it  changes into an Aa flow. Aa flows are characterized by  their jagged,   blocky texture. The majority of the lava here is Aa lava. (Research Source) 

The Bonito Lava flow ranges in thickness from 5 feet at the edge to  over 100 feet in the center. As this lava flowed out from the base of  Sunset Crater Volcano (in the near distance), it had a lot of gas still  dissolved in it. As the gas came out of solution, just like the carbon  dioxide in carbonated drinks, it formed bubbles in the lava.  

Some of these bubbles were frozen in the lava in what are called  vesicles (if you look closely at the immediate foreground deposits you  can see these). Most of the vesicles are small, but sometimes, the gas  accumulates under outer surface of the flow that has cooled forming  large vesicles.  (Research Source) 

In the distance just below the horizon you can see the jagged cliffs of Walnut Canyon National Monument where there are  25 cliff dwelling rooms constructed by the Sinagua,  the very people that had to temporarily leave the area when this volcanic eruption occurred.  

This image is from my ongoing project in which I am trying to raise awareness of the 47% of the USA and 90% of Canada that remain unpopulated wilderness.  

Where Eagles Fly - The American Wilderness Expedition is my personal mission to introduce people to these amazing locations that surround us.  

If you like what you see here upvote then resteemit so that others may experience these wondrous places as well.  

Yehaw!!