Cruising Past Seventy: The Inner Journeys: Driving Down the West Coast: The Cascade Volcanic Arc

Monday, October 4, 2010

Driving Down the West Coast: The Cascade Volcanic Arc

*Part of the trip from Canada to Mexico last year, driving down from the Northwest through the West Coast.

I am from the Philippines, part of the Pacific’s Ring of Fire.  Mt. Baker, Rainier, and St. Helens in Washington, Mt. Hood, Bachelor, Three Sisters, and Adams in Oregon, and Mt. Lassen in northern California are all part of the Cascade Range and its Volcanic Arc, also a segment of the Pacific Ring of Fire that includes over 160 active volcanoes. We all remember the Mt. St. Helens eruption on May 18, 1980 which chopped off 400 meters from its peak, replacing it with a mile-wide horseshoe crater. It was the deadliest and most economically destructive volcanic event in the history of the United States.

Our first stop was Crater Lake National Park. The lake is almost 600 m deep at its deepest point with an average depth (350 m) that is the deepest in the Western Hemisphere and the third in the world. This is due to the nearly symmetrical caldera formed 7,700 years ago during the violent climactic eruptions and subsequent collapse of Mt. Mazama and the relatively moist climate that is typical of the crest of the Cascade Mountains. No streams flow into or out of it. It is re-filled entirely from direct precipitation and water is lost from evaporation or subsurface seepage.

Unlike our first time there during the DUs reunion in Sunriver (please see my post on…), this time the lake was in its full splendor…with its deep blue crystalline waters, so clear you can see the deep down under.   At the crater center stands the pretty Wizard Island beckoning us to fly down. Before reaching the crater, however, we were treated to meadows upon meadows of the Pumice Desert, a very thick layer of pumice and ash, largely devoid of plants due to excessive porosity (meaning water drains through quickly. 

As you drive around the lake, you will reach the far end where the The Pinnacles are.  Pinnacles are formed when the very hot ash and pumice come to rest near the volcano, forming 60 to 90 m thick gas-charged deposits. For perhaps years afterward, hot gas moved to the surface and slowly cemented ash and pumice together in channels and escaped through fumaroles. Erosion later removed most of the surrounding loose ash and pumice, leaving tall pinnacles and spires. Bill and I took turns taking photos of each other among these strange-looking proudly standing outgrowths of the volcanically active land.

Just after the Oregon/California border is the Lava Beds National Monument. The Monument lies on the northeastern flank of the largest total area covered by a volcano in the Cascade Range. Its volcanic eruptions created an incredibly rugged landscape punctuated by these many landforms of volcanism. It has numerous Lava tube caves, with twenty five having marked entrances and developed trails for public access and exploration. It is  geologically outstanding because of its great variety of "textbook" volcanic formations including: lava tube caves; fumaroles; cinder cones; spatter cones; pit craters; hornitos; maars; lava flows and volcanic fields.

We got there close to nightfall and the sand hills around the place took on eerily beautiful hues of brown, red, orange, and gold.  This is where we got to use Vino a lot, going from one lava bed to another.  We struck good images, riding that scooter, against the wide spaces of desert land and scenery.  But we also ate a lot of dust. I felt like a new woman, a bike dude kind of woman (see headline photo). Don’t they call them ‘bitches’? At this NP was where I also saw my first native-American petro glyphs on what is left of the Medicine Lake Volcano.  Legend has it that the lake was wide and high enough for the natives to write on its walls.  Of course, now the land is almost dry and the volcano flat. 

Just a hundred miles from the Park was another volcanic wonder, the Mt. Lassen Volcanic National Park.   The dominant feature of the park is Lassen Peak; the largest plug dome volcano in the world and the southern-most volcano in the Cascade Range. The area is still active with boiling mud pots, stinking fumaroles, and churning hot springs. The National Park is one of the few areas in the world where all four types of volcano can be found (plug dome, shield, cinder cone, and strato).

We took a lot of pictures of the venerable mountain.  But we were hurrying through the mountain roads because a storm was forecasted to hit the area and we did not want to be trapped there.  At the end of the road, however, we were treated to a sight that I had never seen before.  Right by the roadside were fumes of smoke rising from the ground.  All around were hills of different hues of red, orange and brown.  It was as if we had reached Yellowstone!

It was already very dark when we found our campground.  There we rested and planned out our next stops:  Napa Valley, San Francisco, San Jose, Yosemite National Park, and Sequioa National Park.  

3 comments:

  1. Wow! That is a lot of information! Great job of presenting so much information on such interesting places. The pic of Wizard island is awesome.

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  2. Thanks for the compliment! Don't you wish you could go down to the island?

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  3. Thank you so much for your wonderful compliments! I will look into the website! Thanks again!

    ReplyDelete

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