Super Uncool Near Death Trundling - Ghostdancing: Sat Oct 2

[PeteLarose]

I was climbing with a buddy on Saturday afternoon Oct 2 on the north side of the Grand Wall area - near Jingus/Ghostdancing area and was nearly hit by a 20-30 pound rock that missed me by less than six feet. Was belaying my partner from the top of Jingus and the rock came screaming by my head. Was big enough that I could actually see and hear it before it hit me, fortunately. My partner was nearly frozen to the wall he was so freaked out watching his belayer nearly get crushed, and I had to lower him off and GTFO of dodge before something else fell. Saw another party on the ground that said they wanted to climb in the area but they took off because rock was falling around them. We thought we might have heard drills when we got there but they sounded distant.

Who drills and trundles head-sized rocks from 1000 feet up on the Grand Wall on the first sunny weekend in over a month?! Sure the north side doesn't get that much traffic but come on! There was no flagging tape up, no signs, no people on the ground warning, nothing... My 11-month old son nearly didn't have a dad because of this sheer stupidity and negligence.

Saw someone climbing in a yellow/orange jacket to the left (north) and quite a bit higher than the top of NeverNeverLand / Kneewrecker area up quite high on the wall. Looked like the party in question.

Not on here to stir up a bunch more controversy in what seems to be an excessively controversy-filled board already, but come on guys, throw a piece of flagging tape around the entrance or a little sign or something. Or do your work in the rain... not on a warm, sunny Fall day when hundreds of people are all over the place.

[Dooley]

Glad you came away from this without incident, but something really needs to be done cause someone is going to end up seriously injured or dead.

[Ed Seedhouse]

Glad you came away from this without incident, but something really needs to be done cause someone is going to end up seriously injured or dead.

Or even seriously dead.

[Anders Ourom]

Did you hear or see anyone above cleaning, or climbing? The rockfall may have been natural - quite a lot comes down in that area. Anything between/below University Wall and Knee Wrecker is in the firing line, as you can see from the shrapnel below.

[PeteLarose]

We were pretty sure it was caused by climbers - there was a party above us on the north side and it sounded at one point like there was a drill being used. Which leads me to think that perhaps we should have gotten out of there straight away when we heard the drill, but we couldn't tell where it was coming from.

[smallman]

There was another huge rockfall in that area earlier this year in the spring. I agree with Anders in thinking that natural rockfall may be more likely especially given the weather of late.

[Anders Ourom]

It seems to go both ways. I'd be very careful of climbing in that area below other parties, whatever they were doing. Also of climbing there when rockfall occurs. But it also doesn't seem a suitable place to be new routing on a weekend, if that's what was happening. It's something of a fracture zone, with lots of potential missiles, even without digging, levering, and trundling.

[PeteLarose]

I'm cool about it. I got to lead Jingus for the first time. People should just pay attention.

[marc_leclerc]

That was me with the drill in the orange, but I wasn't cleaning and DEFINITELY not trundling. Just put a new belay in and was working my project on a fixed line. I didn't knock any blocks off, and none fell from above me. So whatever came down by 'Jingus the Cat' must have either come from Vulcan's Artery or somewhere below. Vulcan's Artery does have loose rocks entagled in bushes and crap, and there were people walking all over it apparently looking for Squamish Buttress (not sure how that works!)
That is probably the most dangerous spot in the area as far as rock falls goes, rockfall hazard is VERY downplayed in Squamish. Any cragging at the base of a granite monolith comes with inherent risks. But it is good to hear no one was hurt!

[squamish climber]

Marc,

You make an interesting point that rockfall is underestimated in Squamish. I think people have the impression that natural rockfall on Chief granite is extremely rare, especially compared to Rocky Mtn choss. But you have to ask yourself if rockfall may not be that uncommon. I mean the all those fantastic boulders at the base of the Chief could have come from only one place.

I would be interested if anyone knows when the last big rockfall occured on the Chief? I'm talking big enough to take out trees or create a slide path. And what parts of the Chief are more prone to rockfall? You mentioned Vulcan's Artery - that makes sense.

[Anders Ourom]

There are ways to date rockfalls, which have been used in Yosemite and other places. One, of course, is core samples of trees in and beside slide areas, and analysis of the results. (Allowing for fires, etc.) Another is aerial photography, to determine slide boundaries - they often overlap. The most reliable, but expensive, method is to sample the top of the rock, and do radioisotope analysis, which provides fairly specific information as to when the rock became exposed. They've used this in the Valley to date the big rockfalls from the east side of El Cap.

One way of cross-checking is by date of earthquakes in the area, as shown by various methods. The last huge subduction quake on the Juan de Fuca plate was in January 1700, as confirmed by sediments, Japanese records of tsunamis, etc. It must have caused quite a lot of rockfall.

Despite fond beliefs to the contrary, there is frequent minor rockfall in the gullies and other shear zones, e.g. the Vulcan's Artery. A host of causes - human disturbance, thermal flexing, frost wedging, root wedging, and so on.

[Dru]

There was a full on debris flow out of South Gully in 2005? or so that actually blocked Mamquam FSR. And a sizeable rockfall from upper zodiac around 2001.

Mostly though, spontaneous rockfall occurs on either very wet days (high water pressure in cracks) or during freeze-thaw cycles. Rockfall is rarest during sunny days in the middle of a heatwave in midsummer, but it can happen then. Pure thermal flexing (expansion and contraction of the granite) on days with warm days and cold nights (like now) is also a possible initiation mechanism, when the temperature cycles 20 degrees or more between early morning and late afternoon.

[RobWall]

Hi Peter, I guess you will never know if this rockfall was cleaning or natural. Glad you are OK. Thanks to the above for the information, I learned something today from this thread.