Clast Remnants

Because lahars move as a viscous flow, they do not have the degree of internal turbulence of a stream. In fact the flow more closely resembles a lava flow or glacier. One consequence is that they can carry quite delicate objects, items that would be quickly broken up in stream transport. The location shown below is at Tower Bridge over the Toutle River just below the confluence of the South and North Forks. The remains of fragile clasts are still seen, but are rapidly disappearing.

lahar clast 1

 

Photo by James Maynard © 2010 - free use with attribution

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Lahar clast 2 full

Photo by James Maynard © 2010 - free use with attribution

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Lahar clast 2

Photo by James Maynard © 2010 - free use with attribution

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