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A Virtual Field-trip Guide to S P Mountain Just Released by Astrogeology Science Center!

September 29, 2021

If you are interested in volcanology,  you should check out our newly-released virtual S P Mountain Field Guide. S P Mountain is a textbook example of a tephra cone and associated lava flow, located within the San Francisco Volcanic Field, about 30 miles north of Flagstaff, AZ.

The San Francisco Volcanic Field is in northern Arizona, a region belonging to indigenous peoples who have lived here for millennia. SP Mountain is located within this volcanic field, which sits on the traditional land of many indigenous tribes and nations, including the Havasupai, Hopitutskwa, Hualapai, Navajo, and Pueblo tribes, among others past and present. Much of this region and features within it are sacred.

View of South Mountain
View of S P Mountain, centered,  and its lava flow with view looking to the south. Image credit: M. Elise Rumpf, U.S. Geological Survey

The SFVF covers ~1,800 square miles of the southern margin of the Colorado Plateau and contains over 600 volcanoes, ranging in age from 1,000 years up to 6 million years old.  The volcanoes also vary in size, from small tephra cones (for example, S P Mountain is ~820 ft tall) to the towering San Francisco peaks, the remnants of a large stratovolcano.  The tallest of these is Humphrey’s Peak, which is 12,635 feet tall.

S P Mountain directional map
Map to S P Mountain. Map Data: Google, ©2021 Imagery ©TerraMetrics.  

The Astrogeology Science Center has a long history of using the SFVF as a giant classroom to teach scientists, NASA astronauts and engineers, and college students the fundamentals of planetary volcanology.

We recently released both a printable field guide titled “A Geologic Field Guide to S P Mountain and its Lava Flow, San Francisco Volcanic Field Arizona”, as well as a virtual guide in the form of a Story Map titled “SP Mountain Field Guide: Explore a volcano in Flagstaff, AZ”. These guides concentrate on S P Mountain (also known as S P crater), one of the best preserved volcanic cones and lava flows near Flagstaff and is used as an excellent planetary analog in terms of eruption mechanism, morphology, and composition to features found on rocky planetary bodies and even some asteroids. Both guides are freely available and were designed to be inclusive to a range of educational backgrounds.

The S P Mountain Field Guide includes

  • a brief tour of volcanism across the solar system,
  • a brief geologic history of the Colorado Plateau and San Francisco Volcanic Field,
  • background on distributed volcanism and S P Mountain,
  • driving directions and field stops, and 
  • questions for discussion.

By using S P Mountain as a training site and teaching tool for planetary geology with a focus on volcanism, field guide users can gain  a basic understanding of the volcanic processes relevant to S P Mountain and its lava flow and identify different volcanic textures associated with tephra cones.  

Disclaimer: S P Mountain is located on private property, owned by the Babbitt family. The Babbitts generously allow public use of their land, though it is expected that wildlife and cattle are not disturbed, and artifacts and rocks are left in place. Please refrain from smoking or having open flames of any kind while on the land. If you plan to do any sampling, operate drones, or use other instrumentation, please contact the Babbitts at