Canadian landslide caught on film

[WX]

http://www.bbc.co.uk/news/world-us-canada-18857774#

[Phillip Allen]

seems to be a rather low angle of repose

[B_B]

That boat was lucky, sheesh.

[WX]

It's very low angle. The ground wouldn't have been frozen there would it?

[Chip-skiff]

It's very low angle. The ground wouldn't have been frozen there would it?

It's a debris flow. They can occur with rapid snowmelt or extremely heavy rain and are often triggered by an earthquake, a local slip, a dam failure, etc. The soil and water mix into a sort of colloid, which flows quickly and carries rocks, etc. in suspension. They usually take place where there's been serious disturbance of the surface (e.g. after the Mt. Saint Helens eruption, high-angle slips and slides, clearcut logging, wildfires, or large-scale construction).

I've been studying some prehistoric examples near our place.

[Don Kurylko]

That was just a small secondary flow of debris washing into the Lake. Here's a link to pics of the big slide: http://www.cbc.ca/news/canada/britis...s.html?cmp=rss

Not too far from Nelson where I live. 2 dead 2 still missing. Very sad.

[Chip-skiff]

That was just a small secondary flow of debris washing into the Lake. Here's a link to pics of the big slide: http://www.cbc.ca/news/canada/britis...s.html?cmp=rss

Not too far from Nelson where I live. 2 dead 2 still missing. Very sad.

From the photo, it looks like more could come down, if there's more rain. When water lubricates the boundaries between down-sloping sedimentary rock layers, an enormous lot of mountainside can go boom. Hope they have the sense to evacuate the areas beneath similar slopes.

[WX]

It's a debris flow. They can occur with rapid snowmelt or extremely heavy rain and are often triggered by an earthquake, a local slip, a dam failure, etc. The soil and water mix into a sort of colloid, which flows quickly and carries rocks, etc. in suspension. They usually take place where there's been serious disturbance of the surface (e.g. after the Mt. Saint Helens eruption, high-angle slips and slides, clearcut logging, wildfires, or large-scale construction).

I've been studying some prehistoric examples near our place.

We get similar slides around here but not on that scale thankfully.

[Don Kurylko]

I think that's it for this year. We are getting into hot, dry summer conditions now. It will be interesting to see what happens over the coming winter though. That's a pretty steep slope.

There has been a community at Johnsons Landing since the late 1890's I believe. It was serviced by paddle wheelers back then, hence the name. I don't think there was ever a similar event there like this in all that time.

But these kinds of slides are not at all uncommon in these parts. One almost washed out an old railroad trestle just a few kilometers south of Nelson awhile back. A couple of years ago a guy I know was killed in a washout. He went up a creek on his property to see what was blocking his waterline and ran out of luck.