Mammoth Lakes Geology Report

Since we're home schooling, I'm turning today's post over to our son to post his Geology Report.

My Mammoth Lakes

Geology Report

August 21, 2011

This is my geology report. I’m going to take you on an adventure in history that goes through the Devils Postpile, earthquake fault, Hot Creek, and last but not least the Horseshoe Lake tree kill.

Devils Postpile

One day we went to a place called Devils Postpile. At first I thought “oh, this is just another walk in the woods”, but when I saw the basalt rocks I thought otherwise.

It was hard to climb up to the top, but it was worth the effort!

The rocks looked like hexagons, pentagons, and octagons – geometric shapes.  It looked like math class, or a tiled floor.  The sign in the park explained how these rocks were formed.  First, glaciers carved the valley we were standing in out.  Then the basalt flowed out of a volcano and cooled into these awesome shapes less than 100,000 years ago.  Next, more glaciers and rain eroded the basalt and polished it until it looks like the tile floor we see today.

We saw more wildlife on the Devils Postpile and Rainbow Falls hike than anywhere else.  My Dad told me about the killer minibears, a name we made up for the Golden Mantled Ground Squirrels which are everywhere!  To heckle my Mum, we nicknamed them “killer minibears”, as she is paranoid about bears injuring us while we are hiking and camping.  Every time we saw one, we would shout, “look out, another killer minibear!”   By the end of the day, Mum was seeing killer minibears everywhere!

Mercy!  It’s the curse of the killer minibears! 

Hot Creek
The next day, I was playing my video games obviously, but then my dad told us that we were going to go hike.  I protested, but my dad ushered us into the truck anyways.  We drove to a road near the airport, by a fish hatchery, and parked.  There was a sign there that said something like “Warning!  Scalding hot water will boil you alive!” 
The sign didn’t frighten me, and I ran down the hill.

After a short hike by Hot Creek, we saw a very, very hot pool of water steaming and bubbling.  It smelled like sulfur.  The water in the pools was bubbling because it was heated by magma.  The magma is only five miles below our feet around Hot Creek, and that’s close enough to boil the water.  The magma heats gas which floats up through gas vents, and boils the water…kind of like my Dad, who vents gas almost all the time.

When I was doing my research, I found this cool map thing that shows how the trees at Horseshoe Lake were killed.  It helped me understand how the water is boiled at Hot Creek.

Horseshoe Lake Tree Kill
When we were first driving around Mammoth Lakes, we came to a place called Horseshoe Lake, and all of the trees were dead.  We read the sign, and it said that all of the carbon dioxide had killed the trees.  We decided it would be funny to pose as if we were venting gas ourselves, and pretend that we had killed the trees.  Mum didn’t find it so funny.

This reminded me of the signs that we had seen while snowboarding.  I realized if trees are completely enveloped in carbon dioxide, they die.  If I ever get completely enveloped in carbon dioxide and stay there, I die.  Now I get what the Closed Area sign was trying to tell me.  If I’m ever snowboarding and I notice all of the trees around me are dead, I’m going to get away from there!

Earthquake Fault

One day, I was supposed to be doing this Geology report, and I needed “facts”.  So, my Mum and I went to the earthquake fault.  I saw a big, big, deep crack in the ground.  I’m glad I didn’t fall in, because there was still snow in the bottom.  I learned how earthquake faults are made, and that you should never bring snacks to the earthquake fault.  I didn’t learn why snacks aren’t allowed.  I guess it’s either to prevent litter, or prevent attack by killer minibears, or maybe even a real black bear!  Who knows? 

The nice thing about Mum is that she understands how hard it is to do these reports, so I got to rock climb and zip line after that at Mammoth Mountain!

In summary, this was really, really boring.  However, I did learn that most of the mountains around me in Mammoth Lakes were formed by volcanic activity.  I learned that Mammoth Mountain could still erupt, and that the magma under the Earth’s crust is only five miles below my feet in some places here.  I learned that just like my Dad, the Earth passes gas, and this gas can be deadly.  I think Geology is deadly too!