Tieton Burning?

[Peter_Puget]

Heard on the news that the Tieton was buring. Hope they get it under control soon. Sounds like it might be near climbing.

 

Associated Press

 

TIETON, Wash. – The fire burning near Tieton, in eastern Washington, has grown to 1,600 acres.

 

The fire started Wednesday in dry grass on the Oak Creek elk-feeding wildlife area and jumped Highway 12 and the Tieton River.

 

Dispatcher Tami Jordon at the fire information center in East Wenatchee says planes dropped water and retardant overnight to protect homes. She says homes could be threatened Thursday if winds fan the flames.

 

So far no structures have burned, no evacuations have been ordered and no injuries have been reported.

 

[ 08-15-2002, 10:18 AM: Message edited by: Peter Puget ]

[erik]

reading about these fired and similar fires in the lworth area a couple years afo...makes me wonder what effect does this super heating do to the integrity of the bolts and some of the rock?? any ideas people?

[allthumbs]

Erik, I couldn't comment on the your rock question, but if metal bolts get super-heated they'll lose their temper and be weak and brittle.

 

[ 08-15-2002, 10:25 AM: Message edited by: trask ]

[Greg_W]

I don't know about the Tieton rock (basalt?), but I've seen some granite in L-worth that looks crumbly after the fires went through; rock nearby that was protected is sound.

[glen]

Fire and rock... yes, fire can degrade the competence of the rock. Here's how it works: As a fire begins to burn the vegetation adjacent to a rock it starts to heat up the outside of the rock. Silica-based materials have notoriously slow thermal diffusivity (bury your feet in sand at the beach on a hot day- the top is blistering but a few inches below the surface it's nice and cool) so the heat has a hard time penetrating the rock. The short of it is that a strong thermal gradient is set up in the outer inch or so of the rock. Because materials expand when heated, the thermal effects generate an increase in stress in the outerportion of the rock as the outermost rind expands more than the cool center. With sufficient heat, the outermost rind will fracture and pop off. If you wander through an area that has been recently burned, you will see flakes ranging from quarter sized to dinner plate sized (up to about 1.5" thick) lying on the ground where vegetation had piled up against the rock. The bigger the chip, the hotter and more long lasting the fire at that point.

 

So, boulders are more strongly affected than cliffs because it's hard to burn a lot of material on a cliff. Also, the remaining rock is probably just as strong as any of the other rocks out there. In desert climates, granites with greater than about 20% biotite in them will crumble from the thermal stresses associated with the periodic heating from the sun.

 

But I digress....

 

In short, boulders get cracked when crash pads get burned against them, but roped climbs are a-okay. Even the boulders are okay, just a few new holds.

[Dru]

after the big skaha fire in 1994 everything was fine except a few glue-in bolts had the glue cooked and had to be replaced. oh yeah and a few flakes expanded or fell off.

[Dave_Schuldt]

The wind usaly blows from the west so the climbing areas should be OK.

[Griff]

I passed through the Tieton area last week. The burned area was fairly limited and was in the area between The Royal Columns and The Bend. I doubt that it will affect the climbing area.

 

Also, I always thought that, for steel, when it's temper is lost, it becomes soft (and weak) rather than brittle.

At any rate, there should not be a problem in this case.

 

Griff