slot canyons

[cool]

I happened to see a pic of a slot canyon in CA state parks brochure. quite surprised! Do we really have slot canyons in CA?
If we have, I would really be dying to visit it.

I came across a slot canyon in Arches NP and it was amazing!

[Mark Sedenquist]

I happened to see a pic of a slot canyon in CA state parks brochure. quite surprised! Do we really have slot canyons in CA?
If we have, I would really be dying to visit it. I came across a slot canyon in Arches NP and it was amazing!

There is one about 2 miles south of I-15 in Afton Canyon. At the narrowest (navigable) section the slot opening is about 12" wide and about 45 feet tall. It is known as Spooky Canyon.

[LA Native]

Yes there are slot canyons in CA. I just went to a couple a few months ago. See this post for a picture in Anza Borrego.

http://www.roadtripamerica.com/forum...highlight=Anza

And this site

http://www.americansouthwest.net/slo...otographs.html

They range from barely wide enough for a person, to almost as wide as a large street. The ones in Anza are fairly easy to get to, unlike some of the others.

There are a lot of other types of canyons in Southern California, but they're different type of geology than the ones in utah, not as colorful or narrow, but very interesting. I just went down one last weekend, but a lot of them require some climbing gear to get into. I'll try and post a picture of what they look like.

[Quebec Gen]

Sorry for my ignorance, but what exactly is a slot canyon, what makes one canyon a slot canyon? Thanks!

Gen

[Mark Sedenquist]

Sorry for my ignorance, but what exactly is a slot canyon, what makes one canyon a slot canyon?

Photos are probably the best way to illustrate the concept. On this page are several good examples and links to dozens and dozens more. The editors of American Southwest maintain one of the best catalogues of slot canyoneering on the web. If you haven't looked at their site, before -- you are in for a treat.
In general slot canyons are a descriptive term -- most canyons/ravines/arroyos in the west are relatively wide and descend gradually or at least in steps through layers of rock. The Grand Canyon is one example of a such a canyon. SLOT CANYONS on the other hand have near vertical walls and are sometimes hundreds of feet deep but rarely are more than a few feet (or inches) wide. I will post some photos in a day or so.

Mark

[AZBuck]

Gen asked two questions, and Mark answered (concisely and brilliantly) the what IS a slot canyon. As to what MAKES one, let's go to Geology 101. These canyons are invariably incised in sandstone in arid climates. Both conditions are necessary to their formation. They start as cracks in the rock (from seismic activity or freeze/thaw expansion of the rocks) into which a little moisture and a little wind can creep and erode the crack evenly on the sides. They are self-accelerating in that the more they erode, the more sand from the break-up of the bedrock is available for sandblasting the walls and the easier it is for the wind to get in there. The key to their formation is that the walls get eroded evenly in rock that is otherwise relatively competent (self-cohesive), and that there's little overland flow of water to carry off the debris. Too much moisture, too soft a rock and you end up with the more typical V-shaped valleys (or U-shaped if the valley was made by a glacier).

AZBuck

[Mark Sedenquist]

Gen asked two questions, As to what MAKES one, let's go to Geology 101. These canyons are invariably incised in sandstone in arid climates. Both conditions are necessary to their formation. They start as cracks in the rock (from seismic activity or freeze/thaw expansion of the rocks) into which a little moisture and a little wind can creep and erode the crack evenly on the sides. They are self-accelerating in that the more they erode, the more sand from the break-up of the bedrock is available for sandblasting the walls and the easier it is for the wind to get in there...

Great explanation! It is wonderful having a working geologist on this forum!
I should add that it is extremely easy to get lost in slot canyons and I, myself, have spent the better part of a day wandering around looking for the exit in a canyon that only required about 30 minutes to get into. It was a very fun, albeit confusing day. If you go exploring, ALWAYS CARRY EXTRA WATER and a good topo map -- it is amazing how similar the walls can look after a while... And before you post the obvious -- it wasn't possible to simply follow my footsteps out -- in slick rock country one doesn't always leave footprints and also I am ardent believer in hiking where I leave no trace... Sometimes such a policy can yield challenging experiences....

Mark

[Robert Schaller]

I always leave a very tiny trail of bread crumbs or something similar so I can not only find my way out, but I can have little snacks as I go. I'm always hungry by then...

They can't be too big though -- I tried whole Oreos once but squirrels ate them all before I got back. So they have to be small enough so that squirrels don't notice them!

Hey, I'm BACK, and sharper than ever! :) Bob

[Mark Sedenquist]

I always leave a very tiny trail of bread crumbs or something similar so I can not only find my way out, but I can have little snacks as I go.

Hey, I have news for you -- you leave bread crumbs in a slot canyon and you might attract something much bigger in the food chain than you are prepared to deal with...

Hey, I'm BACK, and sharper than ever! :) Bob

That is a scary thought -- but welcome back.

Mark

[Quebec Gen]

Thanks Mark and AZ Buck for your explanations, that's more than what I expected!:-) I'm always interested in learning more about the geology of that part of America. I saw pictures of slot canyons before and I could see that they were different from most of the canyons I saw but I was wondering what was the one thing that made them "slot" canyons.

Welcome back Bob, I hope you didn't leave Oreo cookies everywhere on your way back from Virginia, there will be more road kills just because of you!

Gen who's going to spend the weekend on the beach!:oP