2023年10月31日 · These eruptions culminated 7,700 years ago in the largest explosive eruption in the Cascades during the past 1 million years, and one of the Earth’s largest eruptions in the past 12,000 years (Holocene Epoch). Mount Mazama's climactic eruption produced the caldera where Crater Lake exists today.

Mount Mazama originally had an elevation of 12,000 feet (3,700 m), but following its climactic eruption this was reduced to 8,157 feet (2,486 m). Crater Lake is 1,943 feet (592 m) deep, the deepest freshwater body in the U.S. and the second deepest in North America after Great Slave Lake in Canada.

Mount Mazama, part of the Cascade Range volcanic arc, was built up mostly of andesite, dacite, and rhyodacite over a period of at least 400,000 years. The caldera was created in a massive volcanic eruption between 6,000 and 8,000 years ago that …

2023年10月30日 · The climactic eruption of Mount Mazama devastated the terrain for tens of kilometers from the volcano, sent pyroclastic flows as far as 70 km (43 mi) down every valley heading on the volcano, and produced ash fall throughout much of the Pacific Northwest and parts of southern Canada.

Mount Mazama’s Final Eruption. The cataclysmic eruption of Mount Mazama 7,700 years ago started from a single vent on the northeast side of the volcano as a towering column of pumice and ash that reached some 30 miles (50 km) high. Winds carried the ash across much of the Pacific Northwest and parts of southern Canada.

Decades of detailed scientific studies of Mount Mazama and new maps of the floor of Crater Lake reveal stunning details of the volcano’s eruptive history and identify potential hazards from future eruptions and earthquakes.

Crater Lake partly fills one of the most visually spectacular calderas of the world, an 8-by-10-km (5-by-6-mi) basin more than 1 km (0.6 mi) deep formed by collapse of the volcano known as Mount Mazama during a series of explosive eruptions about 7,700 years ago.

2023年9月8日 · Soon after the caldera formed, eruptions from new vents built the base of Wizard Island, and over several hundred years, rain and snow partially filled the caldera. Meanwhile, Wizard Island continued to grow and three other volcanoes formed underwater. The final eruption was on the east flank of Wizard Island about 4,800 years ago.

The spectacular 8 x 10 km Crater Lake caldera in the southern Cascades of Oregon formed about 7,700 years ago as a result of the collapse of a complex of overlapping shield and stratovolcanoes known as Mount Mazama.

2024年11月21日 · Native Americans witnessed its formation 7,700 years ago, when a violent eruption triggered the collapse of a tall peak. Scientists marvel at its purity—fed by rain and snow, it’s the deepest lake in the USA and one of the most pristine on Earth.