Mt Whitney Webcam
Mt Williamson Webcam
Who's Online Now
0 members (), 52 guests, and 6 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Page 1 of 2 1 2
Mysterious fallen trees near Tioga entrance to YNP
#1349 12/17/09 02:43 PM
Joined: Oct 2009
Posts: 849
Likes: 3
+ @ti2d Offline OP
OP Offline
Joined: Oct 2009
Posts: 849
Likes: 3
Since it is slow, I might as well post while I can!

Coming from the Fuggowhee (Coarsegold) side as you near Tioga Lake near the Tioga Pass entrance in YNP, there is a field off to the right. In that field are fallen trees that have fallen in the same direction.

Rock slide? No. There is no indication of a rock slide. No large rocks, scree or talus to suggest such an event occurred.

Earthquake? There is no strong evidence of any scarp or fault line in this area.

Pyroclastic flow (lahar)? No evidence of scorching on the trees from the superheated. Note: Mt. St. Helens explosion leveled the trees near and around Spirit Lake.

Wind? I strong doubt a windstorm could do this type of destuction. Winds vary.

Volcanic blast? Maybe. Long Valley Caldera blast? That blast happened millions of years ago. The state of decay of the fallen logs suggest a more recent event.

Avalanche? Very strong possibility, hence why the trees seem have fallen in the same direction and seem to have snapped at the base or at their roots. Note: the trees on the other side of the road also follow this same mysterious pattern.

Something to ponder next time you are in the

There...that should liven up things a bit.


Journey well...
Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1350 12/17/09 03:08 PM
Joined: Dec 2009
Posts: 558
Offline
Joined: Dec 2009
Posts: 558
Most likely avalanche, knocks the trees down then melts for no sign of the source.

Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1351 12/17/09 03:50 PM
Joined: Nov 2009
Posts: 1,256
Likes: 2
Offline
Joined: Nov 2009
Posts: 1,256
Likes: 2
Easy - Bigfoot! He finally found the right size toothpick and walked away with that one, leaving all the rest.

There. Lively enough for you? Call me crazy, but I might actually ask a ranger . . .

Re: Mysterious fallen trees near Tioga entrance to YNP
RoguePhotonic #1352 12/17/09 04:41 PM
Joined: Oct 2009
Posts: 849
Likes: 3
+ @ti2d Offline OP
OP Offline
Joined: Oct 2009
Posts: 849
Likes: 3
Fascinating isn't it.

Ah, to wish I was there to see it happen.

What a spectacle it might have been to see.

Thanks, RP!


Journey well...
Re: Mysterious fallen trees near Tioga entrance to
RoguePhotonic #1354 12/17/09 05:28 PM
Joined: Nov 2009
Posts: 582
Offline
Joined: Nov 2009
Posts: 582
Originally Posted By: RoguePhotonic
Most likely avalanche, knocks the trees down then melts for no sign of the source.


Well isn't that a decisive statement for the limited amount of information offered. Gary, a few more questions about the situation:

How many trees?
Which kind of trees (differences in root/branch structures)?
Proximity to other trees?
Where is the field located? Near a slope that might hold snow?
What side of the lake?

...and so on.

Wind could also be a likely culprit, as Tioga definitely gets hit hard and can regularly see zephyrs of 100-150kts in the winter. A localized downdraft could definitely uproot a few things, as it does on the westside to the sequoias fairly regularly.

The slopes under the north of Dana might cause some damage if they let go. But that basin is fairly wide and flat...


Facebook

Flickr Pics

Think outside the Zone.
Re: Mysterious fallen trees near Tioga entrance to
MooseTracks #1355 12/17/09 06:20 PM
Joined: Oct 2009
Posts: 849
Likes: 3
+ @ti2d Offline OP
OP Offline
Joined: Oct 2009
Posts: 849
Likes: 3
Hey, Laura...

In the exposed field, about 100 old pine trees maybe more...

In the slope, too many to count due to the new growth.

Southwest-ish of Tioga Lake.

I still say it may be avalanche by judging how the trees seem to fall in the same direction away from the slope.

Dana? All of the trees have fallen towards Dana.


Journey well...
Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1361 12/17/09 10:26 PM
Joined: Sep 2009
Posts: 1,261
Bee Offline
Offline
Joined: Sep 2009
Posts: 1,261
These trees burned first? (yes/no)(I have driven through the area many times, but never really scrutinized the trees to any degree)

If they were first victims of fire, the subsequent decay would leave them much more vulnerable to any disturbance such as the seasonal winds that blast through the area. IF the trees have the "toothpick" look (no root balls attached; a sure sign of fire) than it would not take a catastrophic event to knock them down. Also, if it were an avalanche, I would be inclined to think that the end result would be more of a piling effect, rather than a uniformed scattering of the trees.

B


The body betrays and the weather conspires, hopefully, not on the same day.
Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1362 12/18/09 01:23 AM
Joined: Dec 2009
Posts: 558
Offline
Joined: Dec 2009
Posts: 558
Quote:
Well isn't that a decisive statement for the limited amount of information offered


=P I actually thought about some of the questions you asked but I assumed if more interesting anomalies were present they probably would have been pointed out, shouldn't assume I know but I did. crazy

Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1363 12/18/09 01:35 AM
Joined: Sep 2009
Posts: 8,505
Likes: 103
S
Offline
S
Joined: Sep 2009
Posts: 8,505
Likes: 103
Those trees are pointing downslope, in the direction of an avalanche decades ago, that swept across Tioga road. The logs were carried out into the open meadow, where the avalanche terminated.

Doggone, this topic sent me off Googling for pictures, and there are few to none. Here's the only one I could find, from Wikipedia's "Avalanche" description:

Wikipedia's caption: "Periodic winter avalanches on this 800 m high slope transport woody debris to the flat in the foreground." (Click on picture to see larger version)






When you come upon one of these avalanche zones, you can see most of the trees tops are pointing in the direction of the avalanche flow. This is likely due to two things: The tree first snapped in the direction of the avalanche flow, and, the effect of their stumps dragging along (as an anchor), while the lighter tops were carried forward by the tumbling snow of the avalanche.






Here's an image of Google's satellite view of the spot + @ti2d is talking about:

You can see the darker areas (trees) on the left (west) side of the road. The lighter areas are where the avalanche stripped away the trees, moving to the right (eastward) across the road. The pointer on the picture shows the lighter objects (possibly the logs).

On the PCT between Sonora Pass and the Yosemite boundary to the south, I recall seeing numerous huge avalanche zones where we could see hundreds of trees all laying like toothpicks pointing downslope. I tried to find a satellite view of them, but the photos were taken with the area completely covered in snow.

Sometimes you can find a zone where the snow cover was several feet deep, and the avalanche flow ran on top of the snow cover. In those places, the trees are all snapped at a similar height, several feet above the ground.

I have seen other places where an avalanche simply piled ALL the trees in one huge jumble. I don't recall where it was (somewhere here on the west side), but I was on a hiking trail where the pile was a mess at least ten feet deep across the trail. Climbing over it was impossible, so we had to make a big bushwhacking detour around the area.


Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1365 12/18/09 02:11 AM
Joined: Nov 2009
Posts: 56
J
Offline
J
Joined: Nov 2009
Posts: 56
There are a few places south of there down Lyell canyon along JMT where you see the same type of trees/logs out in the middle of the meadow towards the river. You're walking along and see it and wonder "How the heck did that get all the way out there!?"

Re: Mysterious fallen trees near Tioga entrance to YNP
Steve C #1366 12/18/09 02:13 AM
Joined: Sep 2009
Posts: 8,505
Likes: 103
S
Offline
S
Joined: Sep 2009
Posts: 8,505
Likes: 103
Talking about avalanches brought back memories of a video posted a while back. It's gone from the Mammoth mtn site, but found it on YouTube. It's triggered by an explosive dropped via helicopter. The video runs 6 minutes.

Here's the YouTube link: Avalanche Mt Ruepehu, New Zealand, 2003




And one from Telluride:




Re: Mysterious fallen trees near Tioga entrance to YNP
Steve C #1367 12/18/09 05:56 AM
Joined: Nov 2009
Posts: 1,256
Likes: 2
Offline
Joined: Nov 2009
Posts: 1,256
Likes: 2
Any doubts about the force and inertia behind an avalanche, that first video is revealing. Notice how far the leading edge travels upward in that bowl?

Re: Mysterious fallen trees near Tioga entrance to YNP
Steve C #1368 12/18/09 08:36 AM
Joined: Oct 2009
Posts: 849
Likes: 3
+ @ti2d Offline OP
OP Offline
Joined: Oct 2009
Posts: 849
Likes: 3
Originally Posted By: Steve C
Doggone, this topic sent me off Googling for pictures, and there are few to none.


Sorry, Steve C, but many thanks for your research. I am just fascinated by odd and curious things I see along the way in my trail of life.

And many, many thanks to all who offered their explanations to the odd and curious in the Sierra Nevada.

Yes, avalanche. Seen the damage done while on SoCal's San Gorgonio's north slope. Fallen trees everywhere blocking the trail.

One day I found an obsidian in the middle of a meadow while looking for wild onions near Tioga Lake in YNP. It caught my eye immediately...all black and shiny. It is about the size of a half-dollar coin. I look around the area and find no others. I ask, "Now how did you get here?"

Yes, I brought it home with me.

Then I get home, turn on the computer...

Come to find out it could be the remnant of the Long Valley Caldera blast or the numerous blasts that have occured near and around Mammoth. I am fascinated with fault lines, plate tectonics, scarps, earthquakes, and volcanos and how they sculpted the Sierra Nevada.

Fascinating.

Will I return the rock to its former spot? Yes.


Journey well...
Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1369 12/18/09 09:34 AM
Joined: Sep 2009
Posts: 8,505
Likes: 103
S
Offline
S
Joined: Sep 2009
Posts: 8,505
Likes: 103
> Come to find out it could be the remnant of the Long Valley Caldera blast or the numerous blasts that have occured near and around Mammoth. I am fascinated with fault lines, plate tectonics, scarps, earthquakes, and volcanos and how they sculpted the Sierra Nevada.

Well... not exactly. That obsidian was put there by humans. ...Native Americans.

Tioga Pass or Mono pass just to the south was a main trading trail for the American Indians. They carried obsidian across the Sierra to trade with others. It was the primary source of arrowheads. It can be found down around Mammoth, Glass Mountain, I believe.

Hiking over Donohue Pass out of Yosemite, as you climb out of the Lyell Canyon there is a place along the trail where there is obsidian lying all over the place ...on top of granite. It must have been an Indian camp where they made arrowheads.

The big effect of the Long Valley Caldera is the expansive volcanic tuff deposit north of Bishop. Every time you drive north on 395, you can see the pinkish-tan cliffs along the Owens River before you climb to the Sherwin summit. That entire smooth but rocky slope up that grade is made of cubic miles of volcanic tuff that exploded out of the caldera in one cataclysmic eruption. (former geology major here).

Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1370 12/18/09 09:46 AM
Joined: Nov 2009
Posts: 1,256
Likes: 2
Offline
Joined: Nov 2009
Posts: 1,256
Likes: 2
Originally Posted By: + @ti2d
One day I found an obsidian in the middle of a meadow while looking for wild onions near Tioga Lake in YNP.

Yes, I brought it home with me.

Will I return the rock to its former spot? Yes.


The Attitude man possesses good wilderness ethics! Now I just need to figure out how to return that shiny rock my daughter "unknowingly" filched from Mt. Rainier a few years ago. And the one from the Grand Canyon. And also the two from Rocky Mountain NP. She didn't quite "get it" between the ages of 3 and 7. No telling what would be in her pack when we returned home.

Hey, since you're in the business of returning missing geological strata . . .

Re: Mysterious fallen trees near Tioga entrance to
Bulldog34 #1372 12/18/09 10:08 AM
Joined: Nov 2009
Posts: 595
Offline
Joined: Nov 2009
Posts: 595
There's another large source of obsidian in the Cosos.

It's quite common for find obsidian flakes thoughout the southern Sierra, Inyos, Cosos, and El Pasos. Once you know what to look for along the edges, it's easy to tell whether the flake occurred naturally, or whether it was done by a human.

Re: Mysterious fallen trees near Tioga entrance to YNP
Steve C #1373 12/18/09 10:56 AM
Joined: Oct 2009
Posts: 849
Likes: 3
+ @ti2d Offline OP
OP Offline
Joined: Oct 2009
Posts: 849
Likes: 3
Originally Posted By: Steve C

Well... not exactly. That obsidian was put there by humans. ...Native Americans.

Tioga Pass or Mono pass just to the south was a main trading trail for the American Indians. They carried obsidian across the Sierra to trade with others. It was the primary source of arrowheads. It can be found down around Mammoth, Glass Mountain, I believe.

Hiking over Donohue Pass out of Yosemite, as you climb out of the Lyell Canyon there is a place along the trail where there is obsidian lying all over the place ...on top of granite. It must have been an Indian camp where they made arrowheads.

The big effect of the Long Valley Caldera is the expansive volcanic tuff deposit north of Bishop. Every time you drive north on 395, you can see the pinkish-tan cliffs along the Owens River before you climb to the Sherwin summit. That entire smooth but rocky slope up that grade is made of cubic miles of volcanic tuff that exploded out of the caldera in one cataclysmic eruption. (former geology major here).


That explains the other mystery, Steve C. Thanks.

In regards to the LVC, what a blast that was back then, huh. You think Red Rock Canyon rock formation to the south was due from the erosion of the Bishop tuff? I just say that due to the color of the Bishop tuff and the RRC...both pinkish in color.

Geology major, eh? I used to be a rockhound during my Boy Scout and 4-H days...

4-H to me now means: hernia, hiccups, hemorrhoids and heartburn.

Yes, I know...TMI TMI TMI

Have fun.


Journey well...
Re: Mysterious fallen trees near Tioga entrance to YNP
Bulldog34 #1374 12/18/09 10:59 AM
Joined: Oct 2009
Posts: 849
Likes: 3
+ @ti2d Offline OP
OP Offline
Joined: Oct 2009
Posts: 849
Likes: 3
Originally Posted By: Bulldog34
Hey, since you're in the business of returning missing geological strata . . .


Send them to me. A good excuse to return to my beloved Mt. Rainier...grew up there in the mid-60s in Spanaway, WA.

Good excuse to return to GC and RMNP, too!


Journey well...
Re: Mysterious fallen trees near Tioga entrance to YNP
+ @ti2d #1382 12/19/09 12:45 PM
Joined: Nov 2009
Posts: 215
Offline
Joined: Nov 2009
Posts: 215
A good example of this is seen in Return Creek canyon northwest of the McCabe lakes on the way up to Virginia Pass. Google satellite the area and you will see several swaths where the trees have been stripped out.


Mike
Re: Mysterious fallen trees near Tioga entrance to YNP
Mike Condron #1385 12/19/09 04:24 PM
Joined: Sep 2009
Posts: 8,505
Likes: 103
S
Offline
S
Joined: Sep 2009
Posts: 8,505
Likes: 103
Mike, thanks for the info. I looked it up and it REALLY shows a great example. Can't find any debris in the satellite view.

I'll try including the view here:


View Avalanche zones in a larger map

And the link to the Google map is here: Link

Page 1 of 2 1 2

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.4
(Release build 20200307)
Responsive Width:

PHP: 7.4.33 Page Time: 1.004s Queries: 55 (0.996s) Memory: 0.6847 MB (Peak: 0.8405 MB) Data Comp: Off Server Time: 2024-03-28 09:22:23 UTC
Valid HTML 5 and Valid CSS