What happened to lake Missoula every few thousand or so years?

It was the largest ice-dammed lake known to have occurred. The periodic rupturing of the ice dam resulted in the Missoula Floods – cataclysmic floods that swept across eastern Washington and down the Columbia River Gorge approximately 40 times during a 2,000 year period.

Why did Glacial Lake Missoula drain?

Glacial Lake Missoula formed as the Cordilleran Ice Sheet dammed the Clark Fork River just as it entered Idaho. The rising water behind the glacial dam weakened it until water burst through in a catastrophic flood that raced across Idaho, Oregon, and Washington toward the Pacific Ocean.

How did lake Missoula form?

Glacial Lake Missoula: At the end of the last Ice Age, a finger of the Cordilleran ice sheet crept southward into the Idaho panhandle, forming a large ice dam that blocked the mouth of the Clark Fork River, creating a massive lake 2,000 feet deep and containing more than 500 cubic miles of water.

How long did it take Glacial Lake Missoula to empty?

It is estimated that the maximum rate of flow was equal to 386 million cubic feet per second. At that rate, the lake probably drained in a few days.

What did Glacial Lake Missoula look like?

Glacial Lake Missoula was as big as Lakes Erie and Ontario combined. The flood waters ran with a force equal to 60 Amazon Rivers. Car-sized boulders embedded in ice floated some 500 miles; they can still be seen today!

How many cubic miles was Glacial Lake Missoula?

500 cubic miles
At its highest level Glacial Lake Missoula covered an area of about 3,000 square miles and contained an estimated 500 cubic miles of water—half the volume of present day Lake Michigan.

What happened after Glacial Lake Missoula broke through the ice dam?

Floods of Change The dam burst and released flood waters across Washington, down the Columbia River, back flooding into Oregon, before reaching the ocean.

When was the last Ice Age in Washington?

Presently, the oldest dated human remains in eastern Washington go back around ~13,000 years, whereas the last Ice Age floods occurred ~14,000 years ago.

How big was the Glacial Lake Missoula?

2,973 mi²
Lake Missoula/Area

How fast did Lake Bonneville drain?

At the peak of the flood, approximately 33,000,000 cubic feet per second (930,000 m3/s) poured over the Snake River Plain at speeds of up to 70 miles per hour (110 km/h) and deposited hundreds of square miles of sediments eroded from upstream.

When was the last Ice Age?

The last glacial period began about 100,000 years ago and lasted until 25,000 years ago. Today we are in a warm interglacial period.

How fast did the waters of Glacial Lake Missoula travel once the ice dam broke millennia ago?

These “ice dams” broke time and again over the millennia, sending walls of ice-laden water, miles wide and hundreds feet deep, racing over the land at speeds up to 80 mph – scouring a fantastic landscape and leaving a fascinating geologic record.

Was there an ice age Lake Missoula?

Earlier, in 1910, another geologist, Joseph T. Pardee, had described evidence of a great ice dammed lake, Glacial Lake Missoula, that had formed during the Ice Age in northwestern Montana. However, Bretz didn’t see the connection between the glacial lake in Montana and the features he described in eastern Washington.

What would happen if the Missoula ice dam burst?

After each ice dam rupture, the waters of the lake would rush down the Clark Fork and the Columbia River, flooding much of eastern Washington and the Willamette Valley in western Oregon. After the lake drained, the ice would reform, creating Glacial Lake Missoula again. These floods have been researched since the 1920s.

What caused Lake Missoula to flood?

At the end of the last Ice Age, about 18,000 to 15,000 years ago, an ice dam in northern Idaho created Glacial Lake Missoula in Montana. The ice dam burst and released flood waters across Washington and down the Columbia River back flooding into Oregon before eventually reaching the Pacific Ocean.

What were the glacial flood events in Montana?

The glacial flood events have been researched since the 1920s. These glacial lake outburst floods were the result of periodic sudden ruptures of the ice dam on the Clark Fork River that created Glacial Lake Missoula. After each ice dam rupture, the waters of the lake would rush down the Clark Fork and the Columbia River,…