In A Nutshell
Oregon’s Crater Lake is the deepest lake in the United States, formed by many, many volcanic eruptions over thousands of years. It’s only with the relatively recent development of sonar that we’ve been able to map the bottom of the lake and understand just how it was formed. Local Native American tribes have known for generations and generations, though, and have passed down stories of volcanic eruptions in their mythologies, describing great spirits who darkened the skies, collapsed a mountain, and hurled fire.
The Whole Bushel
Crater Lake is the deepest lake in the United States, with a maximum depth of 549 meters (1,949 ft). That’s only the current depth, as scientists have found that the lake bed has risen and fallen many times, and the geological formations in and around the lake tell the story of a turbulent volcanic history.
First the myths, then the science.
Myths of the local Native American tribes have been passed down from generation to generation; for how long, we don’t really known because of the oral nature of their storytelling traditions. There are a number of legends surrounding Crater Lake and the creation of not only the lake itself, but also the island in the middle, now known as Wizard Island.
According to one myth of the Klamath tribes, there was once a great battle within their people. One side laid siege to the other, and the besieging group prayed to the Great Spirit for aid. Aid came, beginning with a trembling deep within the Earth. The top of the mountain broke and fell into the Earth, swallowing those that had started the rebellion. When the tremors finally ceased, the warriors saw that the rupture in the Earth had caused the lake to form where there had been none before, and the spirits of the dead had been turned into sea creatures.
Another version of the story more directly references the volcanic activity we now know was responsible for the formation of the lake.
Llao, the god of the Below-World and Skell, god of the Upper-World, both fell in love with the same maiden. There was a great battle between them for her hand, and their quarrel caused the destruction of the mountain La-o Yaina. The mountain began to smoke first, running with fires that threatened to engulf the surrounding area. Three religious men sacrificed themselves in order to stop the destruction, and the fires were finally extinguished by Snaith, who controlled the waters and the storms, bid by Skell to fill the ruinous crater that their fighting had caused.
Yet another version of the story gives a warning as to why any adventurous souls should stay away from the lake. In a fierce battle between the earth and the sky, it’s said that the mountain shook, fire poured from the mouth of the mountain, and flaming rocks and debris in turn fell from the sky and started fires for miles around. Those that lived around the lake—then called Klamath Lake—prayed to the spirits to stop their fighting and sacrificed two of their most religious men. The spirits were appeased, and the storms came and extinguished the fires and filled the lake. They passed the story down from generation to generation, telling everyone to stay away from the lake lest they anger the spirits again.
Now, the science.
The stories of collapsing mountains and fire raining from the skies aren’t just describing a single cataclysmic event, they’re describing part of a 420,000-year-long history of volcanic activity. The original volcanoes were located to the east of what is now Crater Lake, and over thousands of years, these volcanoes went extinct and gave rise to others. Mount Mazama, the volcano that formed Crater Lake, is a relatively young 30,000 years old. Over the centuries, lava and pressure slowly built up within the mountain until it erupted—7,700 years ago.
That eruption spread ash and pumice over most of the Pacific Northwest and southern Canada. The mountain did, indeed, collapse in on itself, weakened by the volume of magma that had been building up over the years. When the tremors stopped, what was once a mountain was now a crater about a mile deep.
Also like the myths, storms came and filled the new crater, called a caldera. And also like the myth that warns people that angering the spirits will cause them to wage war again, scientists think that it’s likely the volcano will once again erupt with potentially tragic consequences.