While
talking on the phone one day with my 111-year-old great-grandmother the topic
of the Devils Tower came up. A retired
geologist, my great granny had explored many regions of the U.S. as well as
parts abroad. I told her I had never
been to the Devils Tower National Monument which made her insist that I come
pick her up from her home in Hazelton, PA, and we both make the drive west to
Wyoming. Living in the southeastern part
of the U.S., I knew I had many miles ahead of me but figured another trip out
with Granny would be well worth it.
Two days of traveling
approximately 1700 miles gave Granny plenty of time to explain to me that
Devils Tower was considered an igneous rock that was formed by intrusion of magma
below the earth’s surface pushing up through sedimentary rock. She continued to explain that an igneous intrusion
is molten magma that cools below the earth’s surface and Devils Tower was
likely formed by softer surrounding sedimentary sandstone and shale eventually
eroding away leaving the harder igneous rock formation.
When we
finally arrived, and I was able to look at this awe-inspiring monument, I could
see the multiple vertical cracks in the grayish colored rock that separated
what Granny offered were often hexagon-shaped phonolite porphyry rocks because
of the white feldspar crystal structure.
The look on
my face must have shown my incredulity at her knowing all this information for
she then offered a customary salty response by stating, “If you don’t believe
me you can look it up on the website: https://www.nps.gov/deto/learn/nature/geologicformations.htm.” She then commenced to pull out a bag full of
climbing gear and head to the park office for a permit, so she could scale one of
Devils Tower’s vertical cracks that day leaving me, once again, shaking my head,
wondering where she got all the energy for such things.
Photo Illustration 1: Devils
Tower Photo courtesy of National
Park Service
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