Authored by Not Wanderlust’s head geologist: Evan Dismukes
Basalt: a type of lava.
Pyroclastic flow: a superheated ash cloud that moves along the ground at high rates of speed.
Stratovolcano: a cone shaped volcano made up of ash, lava and pumice.
Lahar: a mud flow.
Accretionary wedge: the rock and sediment that gets scraped off the plate that is being subducted.
I know I’m currently behind in these posts, but we’ve been insanely busy since the last one. I’m finally being able to write this since I didn’t have any opportunities to do research in the past week (hopping from wifi hotspot to wifi hotspot in Canada doesn’t help). I’ll chose to blame all of this on the U.S. Border Patrol officers that we’ve dealt with over the past week. Everytime we enter Canada it’s a “Hello” and “Enjoy your stay,” but every time we return to the U.S. it’s “do you have written permission from your parents to operate this vehicle?” without even a “welcome home.”
We started out by going to Mount St. Helens, and before we found out that most of the volcano was closed due to snow, we hiked through Ape Cave. Ape Cave is about a mile long cave that used to be a basaltic lava tube. The basalt means that everything down there is black, and being underground for a mile means the only thing you can hear are the cave snakes hissing “yaaaaaassssss.”
Once you escape the cave snakes, you emerge atop the Mount St. Helens National Volcano. Mount St. Helens, as anyone older than a millennial or people in the Pacific Northwest will know, is an active volcano which has erupted as recently as 2008. When I say “erupted” you’re probably thinking of its 1980 explosion, but that is merely one way a volcano can erupt. To compare these two, the 1980 eruption was rated a 5/7 on the volcano rating scale, similar to earthquake or tornado scales, and the only larger type of explosions are from volcanoes like Mount Pinatubo (6/7) or Yellowstone (7/7). When it comes to the 2008 eruption, it was a slow eruption that produced gas, ash clouds and formed some new rock in the caldera. This actually occurred over a 2 year period from 2006 to 2008. Mount St. Helens is a stratovolcano which is classified by how it erupts; for example, Mount St. Helens’ 1980 eruption had pyroclastic flows, lahars and ash explosions. Despite being an active volcano, none of its eruptions have made a dent in the area’s cave snake population. So, if you plan on hiking in the area, I definitely recommend bringing your favorite Yas Cat to protect yourself from the snakes.
Our last stop before Seattle was Mount Rainier, the largest zombie volcano in the region. This is another stratovolcano like Mount St. Helens, but unlike Mount St. Helens, it’s not visible from Mount Hood or Portland and isn’t “active” (it’s “dormant but alive”). That weird designation means that it’s not erupting, but it’s not extinct because earthquakes are recorded as originating from the volcano. These quakes are thought to be a result of magma activity in the core of the volcano. So, it’s kind of like someone who has just died in The Walking Dead, they’re dead but eventually could start moving again.
Being a stratovolcano like Mount St. Helens, it has all the same attributes. However, being a bigger volcano, everything is magnified. Mount Rainier’s larger size allows for larger and more glaciers to exist which fuel the lahars. In past eruptions, this volcano has produced lahars that reach Puget Sound, and the seismic activity has even caused tsunamis in the sound. Other than keeping an eye on the mountain, really the best thing the hipsters in Seattle can do to save themselves is to burn as much coal as possible to melt the glaciers and prevent the lahars burying the city until they get drowned by the tsunamis. Either way, the world wins because we got rid of a large population of hipsters (there is always a silver lining).
After surveying the potential devastation that is modern day Seattle from the top of the Space Needle, we headed over to the coastal rainforests of Olympic National Park. In the center of the park is Mount Olympus which is the largest and most glaciated mountain in the park, and the state, without being a volcano. Originally, this whole area was not part of the continent. If you go to the beaches, you can get a glimpse of how this place came to be. There are plenty of seamounts visible from the beaches of the park. These are what formed the geology of this park by being slammed into the continent, as the Pacific plate subducted under the North American plate, and formed an accretionary wedge. Seeing as this is where La Push and Forks exist, I feel forced to make a Twilight joke, but no one really wants that. Just know that high tide is higher than you think it is. We almost drifted away in the middle of the night because I underestimated where high tide was in relation to my tent.
The last location we reach in this post is the Hoover Damn of the Pacific Northwest, also known officially as North Cascades National Park. Most of the park that you could access by a car were lakes formed by power-generating dams which have high tension power lines running through the park–giving it a weird feel. This area is made up of granite and gneiss that were uplifted and then eroded by glaciers to form the valley. This whole area is still being uplifted and has more glaciers than anywhere in the U.S. outside of Alaska. While the rocks were cool, I was kind of bored by the man-made aspect of the lakes, and I then found that my favorite part about this visit was seeing and hearing a green Lamborghini Murcielago rip around on the canyon roads.
Now, we began our jaunt across the border into the Great White North, only to be confused as to why everything was so expensive. We got to witness some arctic birds prospecting for silver in Tennessee from a bar in Vancouver, but that is the closest thing to geology that is going to exist in this concluding paragraph since there’s no natural concrete in Canada apparently.