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fourteen410 Member
Joined: 23 May 2008 Posts: 2622 | TRs | Pics
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Big rockfall on Aasgard Pass last week (June 30) caught on camera:
drewcoll, KascadeFlat, jaysway
drewcoll, KascadeFlat, jaysway
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gb Member
Joined: 01 Jul 2010 Posts: 6303 | TRs | Pics
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gb
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Thu Jul 08, 2021 12:35 pm
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I believe Dragontail is somehow active geologically. In about 1985 we were nearly killed when a massive rockfall came off the area to the right of the Fin and dropped two thousand feet to the base of Serpentine, covering the moraine 400' distant with about an inch of snow. There were numerous rocks to 15'. We ran out to the far end of the moraine to keep from getting hit. When I reported this at the RS I was told that not long before there was a rock avalanche on Dragontail so massive that it sent a cloud over the peak and people in Leavenworth believed a wildfire had started in that area....
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rbuzby Attention Surplus
Joined: 24 Feb 2009 Posts: 1006 | TRs | Pics
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rbuzby
Attention Surplus
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Thu Jul 08, 2021 12:45 pm
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Finally a vertical video that works for the subject!
Looks like it came off Dragontail then down to the pass area.
Glad it was a Wednesday and not a weekend.
HikingBex
HikingBex
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altasnob Member
Joined: 29 Aug 2007 Posts: 1382 | TRs | Pics Location: Tacoma |
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altasnob
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Thu Jul 08, 2021 1:11 pm
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gb wrote: | I believe Dragontail is somehow active geologically. |
Not sure about Dragontail but 16 years ago there was a proposal to put a particle accelerator under Cashmere Mountain. The site was selected because it was the one of the most seismic stable places in Washington, as the Stuart Range is one giant granite batholith (I believe one of the largest in the US). It ultimately lost out to a location in South Dakota (politics) so now all those scientist get to live in South Dakota rather than Leavenworth.
https://www.washington.edu/news/2004/04/08/uw-physicists-propose-underground-lab-in-washington/
Chief Joseph, zimmertr
Chief Joseph, zimmertr
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gb Member
Joined: 01 Jul 2010 Posts: 6303 | TRs | Pics
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gb
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Thu Jul 08, 2021 1:25 pm
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I've never seen any evidence that any other peak in the Stuart/Enchantments area has much history of recent rockfall. Yosemite is also granite but the area beneath The Three Brothers has had numerous large rockfalls. There have also been a few rockfalls at Glacier Point Apron.
But when I travel other areas in the Cascades or elsewhere with Granitic Rock; other than from recent glacial downwasting (Snowpatch Spire base of Sunshine Route), I don't see other peaks like Dragontail. Active locations seem to be isolated but repetitive. Even in the Sierra with the great and active uplift of rock along the Eastern Crest, I've not seen evidence of similar events.
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fourteen410 Member
Joined: 23 May 2008 Posts: 2622 | TRs | Pics
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I haven't been up Aasgard in 10 years, but I remember there being enough rockfall in early July that I put my helmet on. Nothing as big as this, though.
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cascadeclimber Member
Joined: 04 Sep 2006 Posts: 1427 | TRs | Pics
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I believe Ingalls Creek demarcs a subduction zone, so I'm not surprised that things in the Stuart Range wiggle, shake, shift, and fall down.
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Bootpathguy Member
Joined: 18 Jun 2015 Posts: 1787 | TRs | Pics Location: United States |
Thank goodness the rock fall didn't come down the standard route. I'm sure there were probably a few folks on that ( climbers left ) route
Experience is what'cha get, when you get what'cha don't want
Experience is what'cha get, when you get what'cha don't want
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Snowshovel Member
Joined: 05 Apr 2021 Posts: 252 | TRs | Pics
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cascadeclimber wrote: | I believe Ingalls Creek demarcs a subduction zone, so I'm not surprised that things in the Stuart Range wiggle, shake, shift, and fall down. |
Ingalls creek follows the intrusive contact between the Ingalls ophiolite and the Stuart batholith. Ingalls had been thrust over the Chiwaukum schist prior to the intrusion. This happened about 90 million years ago at a latitude under dispute
But Ingalls creek does not preserve a subduction zone.
Speculation about Dragontail having higher incidences of rockfall are probably partially correct and driven by local jointing and mostly anecdotal. The demise of Girth Pillar could indicate the latter.
The Brothers in Yosemite has been the scene of quite a bit of activity. But Half Dome and the Waterfall area of El Cap have also, and I think they are lithologically distinct from the Brothers.
fjoro
fjoro
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Snowshovel Member
Joined: 05 Apr 2021 Posts: 252 | TRs | Pics
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altasnob wrote: | gb wrote: | I believe Dragontail is somehow active geologically. |
Not sure about Dragontail but 16 years ago there was a proposal to put a particle accelerator under Cashmere Mountain. The site was selected because it was the one of the most seismic stable places in Washington, as the Stuart Range is one giant granite batholith (I believe one of the largest in the US). It ultimately lost out to a location in South Dakota (politics) so now all those scientist get to live in South Dakota rather than Leavenworth.
https://www.washington.edu/news/2004/04/08/uw-physicists-propose-underground-lab-in-washington/ |
Not sure it could be referred to as seismically stable, but it is not known to be cut by active faults, but the study of that is barely touched.
It choice was probably driven by its relative heterogeneity and the ease one could get a mile of cover over the facility
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CC cascade curmudgeon
Joined: 13 Sep 2006 Posts: 647 | TRs | Pics
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CC
cascade curmudgeon
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Fri Jul 09, 2021 4:32 pm
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altasnob wrote: | gb wrote: | I believe Dragontail is somehow active geologically. |
Not sure about Dragontail but 16 years ago there was a proposal to put a particle accelerator under Cashmere Mountain. The site was selected because it was the one of the most seismic stable places in Washington, as the Stuart Range is one giant granite batholith (I believe one of the largest in the US). It ultimately lost out to a location in South Dakota (politics) so now all those scientist get to live in South Dakota rather than Leavenworth.
https://www.washington.edu/news/2004/04/08/uw-physicists-propose-underground-lab-in-washington/ |
It wasn't politics, it was the right call. The Homestake Mine site in S Dakota was already there and already being used for the types of underground physics experiments (neutrino and dark matter detection) proposed underground lab would be doing, it just needed upgrading.
Leavenworth (in general) wasn't thrilled with the idea in any case, you can imagine how many truckloads of debris from the construction of two, 2 three-mile long, tunnels would have to have been trucked out via a small county/forest service road, not to mention that Cashmere Mountain is in the Alpine Lakes wilderness. Leavenworth doesn't want scientists, it wants nutcracker collectors.
First your legs go, then you lose your reflexes, then you lose your friends. Willy Pep
Cyclopath, fjoro, zimmertr
First your legs go, then you lose your reflexes, then you lose your friends. Willy Pep
Cyclopath, fjoro, zimmertr
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shane w Member
Joined: 14 Apr 2012 Posts: 69 | TRs | Pics
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shane w
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Fri Jul 09, 2021 11:09 pm
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Thanks for sharing that video.
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kbatku Questionable hiker
Joined: 17 Sep 2007 Posts: 3330 | TRs | Pics Location: Yaquima |
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kbatku
Questionable hiker
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Sun Jul 11, 2021 10:50 am
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FWIW my geology prof said that the Stewart Range "came from Mexico" and somehow ended up here. They don't know why or how, just that it happened. My money is on aliens
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Snowshovel Member
Joined: 05 Apr 2021 Posts: 252 | TRs | Pics
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kbatku wrote: | FWIW my geology prof said that the Stewart Range "came from Mexico" and somehow ended up here. They don't know why or how, just that it happened. My money is on aliens |
Nick Zentner has a series of three interviews, with Meryl Beck, Darrel Cowens and Ralph Haugerud. Meryl discusses how to him and others the paleo magnetic record is clear, that the Cretaceous magmatic rocks of the west coast solidified and cooled far to the south and were transported on right lateral oblique subduction to the north. Other geologists have arguments with this.
The geologists on both sides are very good
https://www.geosociety.org/gsatoday/archive/11/6/pdf/i1052-5173-11-6-4.pdf
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DadFly Member
Joined: 02 Jul 2012 Posts: 402 | TRs | Pics Location: Redmond |
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DadFly
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Tue Jul 13, 2021 9:25 am
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Purely anecdotal but in the 30 years I have been going up Aasgard pass and Dragon tail there has been a marked decrease in snow and ice over the summer months. Triple couloirs held ice in the shadows until late July.
"May you live in interesting times"
dixon
"May you live in interesting times"
dixon
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