Mad About Science: Crater Lake

By Brenden Bobby
Reader Columnist

There are some things in life that just have to be experienced. Pictures on the internet can’t properly convey the indescribable majesty of some natural places. Crater Lake is one of those places.

Crater Lake.

I had researched tidbits of Crater Lake for book reports in school while I learned about Pacific Northwest history — humdrum factoids that may or may not be useful in a future trivia night at a bar somewhere. None of these things really stuck with me. Almost two hours south of our hotel, I was beginning to question whether or not my wife and I had made the right decision in coming to this national park — it was so remote, our ears must have popped three times just getting to the park gate, and we still had a couple of miles of hiking ahead of us.

All doubt was instantly dispelled the moment we crested the ridge and looked upon one of the most incredible sights in the entire country. Suspended in a massive bowl of shattered rock was a deep sapphire blue lake with a mountain in the middle of it. I can’t convey how awe-inspiring this sight is, it’s something you just have to experience. Those who know, know.

Crater Lake is a volcanic lake nestled in the remnants of Mount Mazama in south-central Oregon. It’s also the deepest lake in America with a maximum depth of 1,949 feet. That’s a full 800 feet deeper than our lake at summer peak.

The depth of the lake is striking when you’re standing on the rim and looking down. It’s a very steep drop from the rim to the water, and an even steeper drop from the edge of the water to the bottom of the lake — yet curiously, a tiny little mountain within the mountain juts from the western side of the lake. That’s Wizard Island, the cinder cone that formed at the heart of the crater after Mount Mazama’s cataclysmic eruption around 7,000 years ago.

A cinder cone is what you think of when you imagine a volcano. It’s the large cone-shaped structure that is formed by gradual release of smaller rock and lava flow, usually with a smaller caldera at the top. This is just the very top of a volcano’s actual structure, but we’ll save the anatomy of a volcano for another article. The important thing to know is that Wizard Island is one of two major cinder cones located within Crater Lake, and the only one visible above the surface of the water. The other is the Merriam Cone, which peaks just below the water’s surface near the northern edge of the lake.

You’re probably more interested in the event that created Crater Lake than the lake itself, and that’s fair. The eruption that created the lake was a monumental event. Mount Mazama’s peak was suspected to have reached at least 12,000 feet in elevation before the eruption. Double that of the lake’s current elevation of 6,178 feet. Don’t forget that the actual crater dips down nearly another 2,000 feet. The eruption displaced between 12 and 14 square miles of rock.

It’s likely that the eruption wasn’t just a massive explosion flinging miles of stone for miles. As the Earth’s mantle heated the gasses and molten rock in the magma chamber beneath the mountain, it caused them to expand. With nowhere to go, this increased pressure — like pinching the bottom of a zit. There was only one direction for all of this material to go, and that was up to the surface. The pressure caused a blast that sent ash and pumice skyward at twice the speed of sound as the magma chamber violently evacuated its contents. These poisonous gasses spilled out and almost instantly killed all life within 30 miles of the volcano.

This eruption likely looked very similar to the eruption of Mount St. Helens in 1980 — at first. It likely took a little over a week for the magma chamber to completely empty, and that’s when something awesome happened. In the course of about three hours, a series of rippling cracks formed in a circular pattern all around the base of Mount Mazama, virtually tracing the shape of the empty magma chamber below. Then, the 12,000 foot mountain collapsed in on itself to fill the vacant chamber below and created a 4,000-foot-deep crater.

Crater Lake is one of the only lakes in the world that isn’t filled by tributaries, making it some of the purest and cleanest water anywhere in the world. Given the volume of water in the lake, it’s projected by the National Parks Service that it must have taken 460 years of melting snow to fill Crater Lake. If you watch the water from the ridge, the water is a pure sapphire blue, and something you have to see to believe.

Crater Lake is also a great place to stargaze, as there is almost zero light pollution in the area. Though I wouldn’t recommend it this time of year due to the cold temperatures, it’s a great place for an aspiring astronomer to take a camping trip for some truly legendary sights of the Milky Way.

My visit here was one of the most incredible journeys I’ve ever experienced, and something that everyone should experience in their lifetime.

Stay curious, 7B.