Mt. St. Helens and Rock Strata Formation


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Rapid Laying Down of Rock Strata:

Since 1980, some 400 feet of stratified rock has been laid down in the immediate blast area of the volcano

  • “Conventional wisdom” however has typically held that it takes millions of years for such rock strata to form 1

On June 12, 1980, another eruption took place that produced 25 feet thick stratified rock in its own right

  • Over the course of a 3 hour stretch, at least 100 distinct layers of rock were laid down
  • Associated pyroclastic flows (fat moving current of super-heated gas and rock) dusted the surrounding valley with layer upon layer of new strata – varying in thickness from fractions of inches to a couple of feet
  • Successive layering was previously believed to take great lengths of time
  • It is believed that flows may have traveled at hurricane speeds and reached temperature in excess of 1000 degree Fahrenheit
  • Instead of being homogenized layers, the strata was made up of fine particles with perfectly defined layers or striation marks 2

The laying down of sedimentary rock has been enough of a problem that the Army Corp of Engineers has been repeatedly called into address dredging in area rivers

  • These include the the Toutle, the Cowlitz, and the Columbia Rivers
  • In the picture here, US Geologists are studying erosion and the severity of sedimentation (laying down of sedimentary rock) along one of the rivers about 1.5 miles from Mt St Helens
  • It was theorized that enough material was dredged in one effort from the Toutle River, that you could build a 12 lane highway one foot thick from New York to San Francisco 3


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This image is of a dam along the Toutle River that is being constructed to try and address the flow of sediment downstream 4


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Strikingly similar features are evidenced across the Grand Staircase-Escalante National Monument in Utah and in the Grand Canyon of Arizona

  • It makes you wonder just how long it might have taken such beautiful formations like this to develop


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