Sunset Crater Fissure
The initial eruption that resulted in the formation of Sunset
Crater Volcano began between 1040 – 1100 AD and possibly during the
winter of 1064/1065 AD along a 6-mile long fissure. Showers of lava
shot up into the air powered in part by gasses that were trapped in
the lava (similar to the way a carbonated drink shoots out of the
can after it is shaken). The trace of this fissure can be seen
extending south-southeastward from Sunset Crater Volcano as a line
of red cinders between the trees.
The eruption quickly localized to the northern
end to form Sunset Crater Volcano.
Human Erosion
Across the valley to the south outside of the National Monument,
off-road vehicles are allowed to run up and down the various other
volcanoes. Evidence of their use is obvious and likely permanent.
The side of Sunset Crater Volcano also had a similar problem when
visitors were allowed to climb the crater (See
Sunset Crater Lava Flow Trail Earthcache). As the logging
requirement, post the number of trails you can count going up from
the US Forest Service recreation area at the bottom of the
valley.
Logging requirements:
Send me a note with :
- The text "GCZ5H4 Cinder Hills Overlook" on the first line
- The number of people in your group.
- Post the number of trails you can see leading up from the
campground at the bottom of the valley,and
- Send me a note with your explanation on why the trails take so
long to dissapear.
The above information was compiled from the following
sources:
- National Park Service, 2005, Lava Flow Trail,
Trail Guide, Sunset Crater Volcano National Monument.
- USGS, 2005, Geology of Sunset Crater National
Monument, How about going on a volcanic field trip?
http://wrgis.wr.usgs.gov/parks/sunset/sunsetft.html
- Hanson, Sarah L. 2003, Roadside Geology:
Wupatki and Sunset Crater Volcano National Monuments, Arizona
Geological Survey, Down-to-Earth 15
- National Park Service, Sunset Crater Volcano
National Monument, Geologic Resource Evaluation.
- Holm, Richard F, and Richard B. Moore, 1987,
Holocene scoria cone and lava flows at Sunset Crater, northern
Arizona, in Geological Society of America Centennial Field Guide –
Rocky Mountain Section, 1987.
Placement approved by the
Sunset Crater National Monument