Rockslide at Uncompahgre Trailhead

[LURE]

Anybody else sleeping at the trailhead Friday night/Saturday morning (14th/15th) hear that? Coming off those cliff bands to the north. It was incredible, the noise must've lasted 15+ seconds followed by those gunshot bangs as the big boulders made their way to the bottom of the hill. I think it was around 3ish in the morning. We camped at the trailhead again saturday night and a smaller slide happened again in the same spot that afternoon. Very cool. Thankfully not in a dangerous place.

[Timothy]

how did you figure out where the slide happened? any photos?

[LURE]

how did you figure out where the slide happened? any photos?

Well for starters, we witnessed the second slide. Because of that it would be safe to assume the second slide occurred in the same area due to what appears to be already unstable rock as a result of the first slide. And among other things my undergrad is in geology so I will brag that I already have a trained eye for discerning small differences in rock textures and appearances - I figured that when I spotted the face on the cliff that looked like "fresher", less weathered rock compared to the rest of the cliff face it must have been the location of the first slide, and also the same place we witnessed the second slide. Just a really cool sound, I've never heard a slide like that.

No pictures unfortunately. I'd say there were about a dozen people sleeping around the trail head that night. We talked to one party that also heard it. Had never been to the trailhead before and arrived in the dark so when I hear that thing kicking up somewhere behind us while sleeping in the back of the truck I started thinking this might be it haha

[Monster5]

my undergrad is in geology

Yeah, as if that wasn't obvious by the plaid short-sleeve shirt in the profile picture.

[LURE]

my undergrad is in geology

Yeah, as if that wasn't obvious by the plaid short-sleeve shirt in the profile picture.

LOLOLOLOLOL

[Timothy]

your post got me to wondering whether that area might be less stable than others, like some areas have more volcanic activity than others. I'm guessing you are familiar with the Slumgullion earthflow (to the south of Lake City, not all that far from Uncompahgre.

my undergrad is in geology

yeah, I took some geology classes as an undergrad: schist, gneiss, and all that. Right up until my geologist brother in law encouraged me to major in something else (he now owns a replacement windshield business).

[LURE]

your post got me to wondering whether that area might be less stable than others, like some areas have more volcanic activity than others. I'm guessing you are familiar with the Slumgullion earthflow (to the south of Lake City, not all that far from Uncompahgre.

my undergrad is in geology

yeah, I took some geology classes as an undergrad: schist, gneiss, and all that. Right up until my geologist brother in law encouraged me to major in something else (he now owns a replacement windshield business).

Yeah, the San Juans are generally less stable, not very resistant stuff. I feel like the Grenadiers are the only real big chunks of exposed granitic/igneous rock in the whole range. I'm actually not familiar with that earthflow, I have heard that word Slumgullion before though.

With the rain and how wet the Uncompahgre area was it wasn't suprising to me that stuff was falling apart like that before our eyes. Obviously it's always happening otherwise talus slopes wouldn't exist but those rock failures we heard were pretty dramatic, nothing like the lone rock you often hear in the middle of the night bounding down the slope.

[Timothy]

funny, I grew up hiking the San Juans but don't remember them being particularly unstable.

The Slumgullion earthflow is clearly visible as you head south from Lake City on highway 149. It started about 700 years ago and is still moving as evidenced by the trees leaning over at weird angles.

[LURE]

funny, I grew up hiking the San Juans but don't remember them being particularly unstable.

The Slumgullion earthflow is clearly visible as you head south from Lake City on highway 149. It started about 700 years ago and is still moving as evidenced by the trees leaning over at weird angles.

Well I guess it depends on how you use the word unstable. A lot of volcanic rocks are going to erode and react with the atmosphere more readily than crystalline igneous and metamorphics - the San Juans are dominantly composed of volcanic rocks - that's what I'm getting at. Then think about the sedimentary strata of the Bells compared to the chunk of igneous that is Capitol, which one are you more afraid of falling apart on you? Similar situation with volcanics versus igneous.

Whereabouts is this Slumgullion flow taking place again? Sounds fascinating. I'm sure it's such a large scale thing that you don't just simply go "see it". Kind of a regional thing I'm sure.

Edit: I should clarify, cause I'm a bad geologist who half doesn't know what I'm talking about anymore - we're talking intrusive igneous, someone could call me out that igneous is blanket enough term to include volcanic strata like the San Juans. Whatever. There's a reason that I didn't actually pursue a career in pure geology

[rijaca]

The Slumgullion earthflow is clearly visible as you head south from Lake City on highway 149. It started about 700 years ago and is still moving as evidenced by the trees leaning over at weird angles.

Whereabouts is this Slumgullion flow taking place again? Sounds fascinating. I'm sure it's such a large scale thing that you don't just simply go "see it". Kind of a regional thing I'm sure.

slumgullion earth flow.jpg

[workmanflock]

funny, I grew up hiking the San Juans but don't remember them being particularly unstable.

The Slumgullion earthflow is clearly visible as you head south from Lake City on highway 149. It started about 700 years ago and is still moving as evidenced by the trees leaning over at weird angles.

Well I guess it depends on how you use the word unstable. A lot of volcanic rocks are going to erode and react with the atmosphere more readily than crystalline igneous and metamorphics - the San Juans are dominantly composed of volcanic rocks - that's what I'm getting at. Then think about the sedimentary strata of the Bells compared to the chunk of igneous that is Capitol, which one are you more afraid of falling apart on you? Similar situation with volcanics versus igneous.

Whereabouts is this Slumgullion flow taking place again? Sounds fascinating. I'm sure it's such a large scale thing that you don't just simply go "see it". Kind of a regional thing I'm sure.

Edit: I should clarify, cause I'm a bad geologist who half doesn't know what I'm talking about anymore - we're talking intrusive igneous, someone could call me out that igneous is blanket enough term to include volcanic strata like the San Juans. Whatever. There's a reason that I didn't actually pursue a career in pure geology

Interesting thread. I'm pretty sure you can see the slide up Slumgullion Pass just a few miles out of Lake City. There's an obvious pullout that occasionally has artists stationed there.

[LURE]

Ohh I see, real cool! I'll have to check that out next time I'm down there. I was thinking much larger scale, slow, earth movement than that.