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The Big Fill Slide - And Landslides Generally · PlanetGeo: The Geology Podcast

• 0:02
  SPEAKER_00: Welcome to Planet Geo, the podcast where we talk about our amazing planet, how it worked, and why it matters to you.
• 0:13
  SPEAKER_00: Hey there, just a quick note before we get started with this episode.
• 0:16
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• 0:23
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• 0:25
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• 0:30
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• 0:33
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• 0:43
  SPEAKER_00: Thanks and enjoy the show.
• 0:51
  SPEAKER_00: What does that mean you're all ready?
• 0:53
  SPEAKER_00: You're like perpetually ready to record?
• 0:55
  SPEAKER_00: Stop asking.
• 0:56
  SPEAKER_02: Have I ever said, because you ask this question all the time.
• 0:59
  SPEAKER_02: Have I ever said, well, Jesse, no, I'm not ready.
• 1:02
  SPEAKER_02: Hold on.
• 1:02
  SPEAKER_02: I need a I need a few minutes.
• 1:04
  SPEAKER_02: Have I said that ever?
• 1:06
  SPEAKER_00: Uh no, not in the last like four years.
• 1:09
  SPEAKER_00: Maybe in the first couple episodes.
• 1:11
  SPEAKER_00: First couple episodes we did that a bit, but not recently.
• 1:14
  SPEAKER_00: No, that's true.
• 1:15
  SPEAKER_00: I I want you to get your professional game face on.
• 1:18
  SPEAKER_00: It's more of a signal of Chris, hey, tighten it up.
• 1:20
  SPEAKER_00: Let's go.
• 1:23
  SPEAKER_00: The red light is blinking, man.
• 1:25
  SPEAKER_00: Let's go.
• 1:28
  SPEAKER_02: I can see the red light.
• 1:29
  SPEAKER_02: It's right in front of me too, Jesse.
• 1:30
  SPEAKER_02: It's not just on your end.
• 1:32
  SPEAKER_02: So I know we're going.
• 1:33
  SPEAKER_02: And uh you don't have to worry about me.
• 1:36
  SPEAKER_02: You worry about yourself.
• 1:37
  SPEAKER_02: Okay.
• 1:37
  SPEAKER_02: Can we do that?
• 1:38
  SPEAKER_00: I've got fun, Chris.
• 1:41
  SPEAKER_00: You have an interesting Chris today.
• 1:42
  SPEAKER_00: How about that?
• 1:43
  SPEAKER_00: I have interesting Chris.
• 1:44
  SPEAKER_00: Oh, this is very exciting.
• 1:45
  SPEAKER_00: Okay.
• 1:46
  SPEAKER_00: Interesting Chris is the best.
• 1:48
  SPEAKER_00: You tapped into it right away.
• 1:49
  SPEAKER_00: Slightly maybe unpredictable, but enthusiastic.
• 1:54
  SPEAKER_00: He's going to be passionate about something.
• 1:56
  SPEAKER_00: Interesting Chris could have many, many varieties of insight or rants, maybe.
• 2:02
  SPEAKER_00: Let's put it one way.
• 2:04
  SPEAKER_00: I have a few on this.
• 2:05
  SPEAKER_00: Yeah.
• 2:06
  SPEAKER_00: Okay.
• 2:07
  SPEAKER_00: So this is a listener question.
• 2:08
  SPEAKER_00: This mostly a listener question.
• 2:10
  SPEAKER_00: We'll credit Ron with this.
• 2:12
  SPEAKER_00: Ron, thanks for the question.
• 2:13
  SPEAKER_00: Brought up that we we like to talk about geoscience news things and also pointed us in the direction that, hey, there's some news about a place you guys are passionate about, which is the Tetons and the landslide that happened in the Teton Pass just recently.
• 2:27
  SPEAKER_00: At the time of recording, Chris, you're about to depart on Summer Science.
• 2:30
  SPEAKER_00: This will come out while you're on Summer Science.
• 2:33
  SPEAKER_00: And do you cross this road with the big yellow school bus?
• 2:36
  SPEAKER_00: Uh, do you go across Teton Pass or no?
• 2:39
  SPEAKER_02: No, we don't.
• 2:40
  SPEAKER_02: Um, but I've crossed the pass many, many times.
• 2:43
  SPEAKER_02: Everybody knows this.
• 2:44
  SPEAKER_02: If you've listened to the podcast before, then you know that Jenny and I and my kids have been in a rut for quite a while where we we spend you know several weeks in the summer banging around a large part of the Tetons, and we've been doing that for for quite a while.
• 2:59
  SPEAKER_02: So, yes, we've crossed the Teton Pass because I don't know how this came about.
• 3:05
  SPEAKER_02: Jesse, do you can I tell the story of the brewery?
• 3:08
  SPEAKER_02: Do you want me to like talk about that?
• 3:09
  SPEAKER_02: I don't know.
• 3:10
  SPEAKER_00: I've lost control of you in this podcast, so please have interesting Chris today.
• 3:14
  SPEAKER_00: So here we go.
• 3:15
  SPEAKER_00: The benevolent side of my dictatorial role is coming out.
• 3:18
  SPEAKER_00: I'm being benevolent now.
• 3:20
  SPEAKER_00: All right.
• 3:21
  SPEAKER_02: So Jenny and I we went to Grand Teton Brewing Company.
• 3:26
  SPEAKER_02: I don't know how many years ago.
• 3:28
  SPEAKER_02: I'm gonna just say six or seven years ago.
• 3:30
  SPEAKER_02: That's that's probably ballpark-ish.
• 3:32
  SPEAKER_02: And we walk into this place, and this is in Idaho.
• 3:35
  SPEAKER_02: This is this is obvious.
• 3:38
  SPEAKER_02: Yeah, yeah, you gotta go over Teton Pass.
• 3:40
  SPEAKER_02: And so we come into Victor and we saw a sign, and we go there, and it's just this really cool, it's got a cool vibe to it.
• 3:48
  SPEAKER_02: And we had a deck of cards with us and a cribbage board, so we're just gonna sit there, have a beer or two, and just hang out with the kids.
• 3:55
  SPEAKER_02: And you get to look at the back side of the Tetons from this place, so it's pretty amazing.
• 3:59
  SPEAKER_02: It's a view that I've said this before that a lot of people don't get to appreciate because I think everybody views it from Jackson Hole.
• 4:07
  SPEAKER_02: So I we walk in and Jenny notices on the board where they're displaying the beer name.
• 4:11
  SPEAKER_02: She she says, Oh, Chris, they have bitch creek here.
• 4:14
  SPEAKER_02: And we had just purchased Bitch Creek Ale at somewhere else in in Wyoming.
• 4:20
  SPEAKER_02: And uh there was a guy sitting in the corner of the bar area there, and he perks his head up and he says, Oh, did you like Bitch Creek?
• 4:28
  SPEAKER_02: And Jenny and I look at him and we turn our heads, you know, and is this kind of older gentleman?
• 4:33
  SPEAKER_02: And I said, Yeah, we really did.
• 4:35
  SPEAKER_02: And and I kind of we talked to him for just maybe 30 seconds or so, and I'd be like, Are you a brewer or do you own this place?
• 4:42
  SPEAKER_02: And he's like, I don't own it, but I'm I'm the head brewer here.
• 4:45
  SPEAKER_02: And so we I said, Well, I brew beer, and and it we just had a really good discussion.
• 4:49
  SPEAKER_02: And then he's like, you know, grab your glasses, let's go for a tour, and I'll keep your glasses full.
• 4:55
  SPEAKER_02: So two or three took us all around, yeah.
• 4:57
  SPEAKER_02: Yeah, took us all around.
• 4:59
  SPEAKER_02: So we spent way longer there than we ever thought we would, but just a good time.
• 5:03
  SPEAKER_02: So we've been going back ever since.
• 5:05
  SPEAKER_02: It's uh it's a destination for us now.
• 5:07
  SPEAKER_00: So totally.
• 5:08
  SPEAKER_02: But not with the bus, okay.
• 5:10
  SPEAKER_02: We don't I don't take I don't I've never taken the bus over Teton Pass, actually.
• 5:13
  SPEAKER_00: Okay, yeah.
• 5:14
  SPEAKER_00: I mean it's one of these like classic two-lane winding highway roads, right?
• 5:19
  SPEAKER_00: I mean, it you kind of snake your way up and down uh on various sides, and we'll get into this this episode.
• 5:25
  SPEAKER_00: It's a complicated engineering project and feet for many reasons, but the story here is that there was a landslide.
• 5:31
  SPEAKER_00: There's a landslide recently, it's called the Big Fill landslide, and we're gonna talk about why that is.
• 5:36
  SPEAKER_00: But the road is closed for an unknown amount of time, quite a long time, probably, to fix this landslide.
• 5:42
  SPEAKER_00: If you look at photos, if you go to Google and just type in Big Phil landslide or Teton landslide, you'll see some photos of this.
• 5:48
  SPEAKER_00: I mean, so there's an interesting story to this, there's an interesting geological story to this, and we're gonna, I think, Chris, start zoomed in on the big fill landslide and then zoom out to landslides generally, and then kind of talk about this region, landslides in this region, which you've taught a lot about landslides in this region over the years.
• 6:07
  SPEAKER_00: So the story of the bigfill landslide is kind of an interesting one, right?
• 6:11
  SPEAKER_00: Like it's been they've known that this road is a problem for a while.
• 6:14
  SPEAKER_00: There's always been some amount of what's called mass wasting or sort of downslope soil or mass movement.
• 6:22
  SPEAKER_00: Mass wasting is movement downslope of mass.
• 6:25
  SPEAKER_00: That's really kind of the definition, right?
• 6:27
  SPEAKER_00: Is that how you focus on that?
• 6:29
  SPEAKER_00: I mean, we've known that this place is moving for a while.
• 6:31
  SPEAKER_00: It's just at what rate?
• 6:33
  SPEAKER_02: When you have steeply tilted sedimentary rocks, you know, you put a road on it too, then you add fill on top of those rocks and soil, and this is called the big fill because they added quite a bit of fill material to make this happen.
• 6:47
  SPEAKER_02: You know, you just have the recipe for this kind of thing.
• 6:51
  SPEAKER_02: So, as you said, they this is not an uncommon phenomenon.
• 6:55
  SPEAKER_02: In fact, Jesse, as I was looking into getting ready to do this episode, I saw a map.
• 7:00
  SPEAKER_02: Did you come across this?
• 7:01
  SPEAKER_02: I'm not sure.
• 7:02
  SPEAKER_02: A landslide map of the southern Teton range there in the it's unbelievable, Jesse.
• 7:11
  SPEAKER_02: It is absolutely shocking the number of landslides that have happened.
• 7:16
  SPEAKER_02: That's all this was.
• 7:17
  SPEAKER_02: This was not like a risk assessment, this was a record of what's happening.
• 7:25
  SPEAKER_00: So the the story here is that this landslide just gave way recently, a couple weeks ago at the time of recording.
• 7:31
  SPEAKER_00: But we kind of had known that this road, this part of the road and several parts along this same road have been a problem, meaning there is movement.
• 7:40
  SPEAKER_00: And on the order of a millimeter per year, those things that happen, that's fixable.
• 7:45
  SPEAKER_00: You know, they go in and patch the road.
• 7:47
  SPEAKER_00: And if you look at photos, you'll see a big patch in this part of the road that eventually gave way.
• 7:51
  SPEAKER_00: So it had been patched before over the over time, and that's kind of natural.
• 7:54
  SPEAKER_00: As soil settles gradually, that happens, but it's not a problem unless it completely gives way, like this did.
• 8:01
  SPEAKER_00: And this was discovered, Chris, by a motorcyclist.
• 8:05
  SPEAKER_00: Actually, was driving over it and actually had I couldn't figure out the fate of this person.
• 8:09
  SPEAKER_00: So I don't think yeah, that's a good thing.
• 8:13
  SPEAKER_02: I'm not sure either.
• 8:14
  SPEAKER_02: Um, I think so, but uh again, I I'm I'm not sure.
• 8:19
  SPEAKER_02: But yeah, this person was driving the motorcycle around this bend and the road just shifted about a foot, it slumped down about 12 inches and it caused him to lay down his bike.
• 8:31
  SPEAKER_02: Yeah, but if you think about that though, I mean that's really bad that this accident happened, but you think about that if that hadn't happened, the disaster could have been way worse.
• 8:43
  SPEAKER_02: Because of this motorcycle accident, they started to assess the area.
• 8:46
  SPEAKER_02: They looked at the crack and they're they started to assess it.
• 8:49
  SPEAKER_02: So they saw that on June 7th, the day after this, it was moving down slope one inch per hour.
• 8:56
  SPEAKER_02: Yeah.
• 8:56
  SPEAKER_02: Well, then just before it finally just gave way, it was moving six inches an hour.
• 9:03
  SPEAKER_02: And so when it all started, this kind of crescendo started because of this accident.
• 9:08
  SPEAKER_02: And because of that, they shut down the road and and potentially then a lot of other lives were saved.
• 9:14
  SPEAKER_00: Yeah, no, that's exactly right, Chris.
• 9:15
  SPEAKER_00: And so those those rates are important because we think of millimeters per year is sort of not a problem.
• 9:21
  SPEAKER_00: You know, that that happens, that's patchable, that's fixable.
• 9:24
  SPEAKER_00: But when we start to get to obviously inches per hour, then this is an unsafe environment.
• 9:29
  SPEAKER_00: And the likely causes of this is very common in the landslide world.
• 9:34
  SPEAKER_00: The most common cause of landslides is water in the system, saturating the rock or soil with water.
• 9:42
  SPEAKER_00: And we'll come back to this topic.
• 9:43
  SPEAKER_00: This will be a theme throughout the episode.
• 9:45
  SPEAKER_00: This was an exceptionally fast snow melt year, so temperatures rose rapidly, a lot of snow melt, saturated the soil, actually saturated the native soil beneath the road fill, which the mud in that native soil then gave way.
• 10:00
  SPEAKER_00: So the native soil underneath the road fill gave way, then took the road fill with it, which caused this big fill landslide.
• 10:07
  SPEAKER_02: That's right.
• 10:07
  SPEAKER_02: The water essentially, Jesse, exploited the boundary between the fill material and the native soil and the rock below it.
• 10:15
  SPEAKER_02: Yeah.
• 10:16
  SPEAKER_02: You know, they're just not the same lithology, they don't have the same porosity and permeability.
• 10:20
  SPEAKER_00: Let me interrupt you right there, Chris, because that's a really important point.
• 10:23
  SPEAKER_00: Because what we typically try and not put into soil that we're filling in a road with is clay, because we've talked about clay and we'll talk about clay again.
• 10:31
  SPEAKER_00: But clay gets really slippery when wet.
• 10:34
  SPEAKER_00: It's a slippery when wet road sign on it, right?
• 10:37
  SPEAKER_00: And there's a your clay layers down in the native soil horizons that got saturated, and then this is a mechanism to start the slip going on, and then the landslide.
• 10:47
  SPEAKER_00: So, Chris, I is now a good time to kind of back up a little bit or zoom out a little bit and talk about landslides generally and leave the big fill and come back to this region later, or or do you is there something else you want to say?
• 10:57
  SPEAKER_02: Yeah, I just have a couple of things, maybe just real short, that I want to bring to the table with this big fill slide that took place.
• 11:04
  SPEAKER_02: One is that we had some really, really warm days and warm nights, and that added water to the system for melt, snow melt from above.
• 11:14
  SPEAKER_02: You had a already high groundwater table, and then there are other things going on that contribute to this too.
• 11:22
  SPEAKER_02: You have climate change, adding more severe storms and more severe seasons to this picture, plus Jesse, uh the impact of forest fires, which are of course probably tied to climate change as well.
• 11:35
  SPEAKER_02: You know, it's just kind of like uh this perfect storm really that led to the situation.
• 11:40
  SPEAKER_02: But again, they've always had their eye on this because it's a very, very steep area.
• 11:46
  SPEAKER_02: A lot of fill was involved.
• 11:48
  SPEAKER_02: By the way, too, Jesse, the fill that adds weight to an already over steepened slope.
• 11:55
  SPEAKER_02: So they had their eye on this.
• 11:56
  SPEAKER_02: They there's no way to predict something like this.
• 11:59
  SPEAKER_02: You know what I mean?
• 12:00
  SPEAKER_02: Like you can't there's no way to forecast it, but you know that it's it's something is gonna happen at some point in the future.
• 12:09
  SPEAKER_00: I think that's a really interesting point to touch on, Chris.
• 12:11
  SPEAKER_00: Is first of all, I didn't know before looking into this that this was a landslide that included non-native rock and soil or infill, that this was road infill fundamentally underneath the road.
• 12:25
  SPEAKER_00: This was human added soil and rock and material that filled in underneath the road.
• 12:31
  SPEAKER_00: And that was on top of the native soil, right?
• 12:33
  SPEAKER_00: So the native landscape got filled in to support this road on a bend in the on a switchback in the mountain pass, right?
• 12:40
  SPEAKER_00: So that's one thing to kind of keep in mind, or one thing that's important.
• 12:44
  SPEAKER_00: The other thing to keep in mind here is that, as you said, this was a known area, but not necessarily a problematic area.
• 12:53
  SPEAKER_00: And that's something that I don't think is necessarily intuitive.
• 12:56
  SPEAKER_00: We think in our sort of basic, you know, human mindframe, if the soil's moving at all, it's a problem.
• 13:01
  SPEAKER_00: But actually that's not the case.
• 13:03
  SPEAKER_00: Like soil is kind of always moving, and so the engineers always consider it to be moving, it's the rate that matters, right?
• 13:09
  SPEAKER_00: So very slowly moving doesn't matter.
• 13:12
  SPEAKER_00: Very fast moving does matter, and catastrophically moving like this does really matter.
• 13:17
  SPEAKER_00: So if it's moving slowly and predictably, that's not a problem.
• 13:21
  SPEAKER_00: And that's what this was doing, you know, prior to this year.
• 13:23
  SPEAKER_00: And then, as you said, all the factors that contributed to this made this a what's called a catastrophic landslide, which means it it slumped away and it's gone now.
• 13:31
  SPEAKER_00: So that I think is a really kind of important thing to touch on there.
• 13:35
  SPEAKER_00: That I think that we don't often appreciate the fact that soil's always moving, it's just the rate that actually matters.
• 13:41
  SPEAKER_00: So, anyway, should we move on and sort of zoom out here?
• 13:45
  SPEAKER_00: Because I want to ask you, Chris, what do you teach?
• 13:47
  SPEAKER_00: What do you talk about in your class?
• 13:49
  SPEAKER_00: Because you know, you teach effectively AP geology, and you cover way more content than I do in the college-level geology class just because you have a full year really to do it.
• 13:58
  SPEAKER_00: How much do you cover in mass wasting and do you get into the differences between slides and falls and topples and all that kind of stuff?
• 14:06
  SPEAKER_02: Um, okay, that's that's a big question.
• 14:08
  SPEAKER_02: That was a typical Jesse Remant question right there.
• 14:11
  SPEAKER_00: Chris, I'm giving you the freedom to take it.
• 14:13
  SPEAKER_02: A question with 15 parts on it.
• 14:14
  SPEAKER_00: Yeah, yeah.
• 14:15
  SPEAKER_00: You get to pick whichever one you want.
• 14:18
  SPEAKER_02: Jesse, well, first of all, I want to ask you do you get to teach mass wasting in your class, your equivalent class at Penn State?
• 14:26
  SPEAKER_02: You do.
• 14:26
  SPEAKER_02: I do.
• 14:26
  SPEAKER_02: And again, because I I'm interested in this.
• 14:28
  SPEAKER_00: Because I teach the engineers, I I I kind of have to.
• 14:31
  SPEAKER_02: You kind of how much time do you spend on it?
• 14:34
  SPEAKER_00: You know, not a lot, as with all of the things, but I cover the basic differences between the rates of flow across the different categories of mass wasting, basically, you know, what the the differences are, and then we kind of get into the categories of how the like how the mass is moving down, if it's falling, that's different from if it's slumping versus different from creep, you know.
• 14:57
  SPEAKER_00: So really general categories.
• 14:59
  SPEAKER_02: Yeah.
• 14:59
  SPEAKER_02: Yeah, okay.
• 15:00
  SPEAKER_02: I do the same thing.
• 15:01
  SPEAKER_02: I I cover the basic categories with you know, falls and slides and flows and creep.
• 15:08
  SPEAKER_02: And I do that.
• 15:09
  SPEAKER_02: Uh I love, first of all, I want to just say that mass wasting is actually one of my favorite things to teach.
• 15:15
  SPEAKER_02: It's an interesting thing because my students, when when we first get into mass wasting, they look at the word mass wasting and it doesn't make sense to them.
• 15:23
  SPEAKER_02: Like, what the heck is this?
• 15:24
  SPEAKER_02: Well, you know, why what is mass wasting?
• 15:26
  SPEAKER_02: What is the thing that you're speaking of right now?
• 15:29
  SPEAKER_02: And that's always an interesting thing.
• 15:31
  SPEAKER_02: But what I've done, Jesse, is I have uh compiled because the over the last decade there are so many events that have been recorded video-wise, and so I've compiled the best ones and I just put together a presentation of these separate events that are just so gripping.
• 15:53
  SPEAKER_02: I mean, I I don't know how else to say it, they're amazing.
• 15:56
  SPEAKER_02: And then if you use Google Earth and diagrams that geologists have drawn of the area that this event happened, then you start to look at okay, why did this happen here?
• 16:08
  SPEAKER_02: All right, first of all, was this a good idea to put a road here?
• 16:12
  SPEAKER_02: You know, um, are the rock layers tilted the right direction to put a road in this particular valley?
• 16:20
  SPEAKER_02: You know, because there are things that you should do and there are definitely things that should not be done.
• 16:26
  SPEAKER_02: And it's amazing and shocking to me how often things are done in a way that just doesn't make any geologic engineering sense at all.
• 16:37
  SPEAKER_00: That kind of came to my mind in looking at this.
• 16:40
  SPEAKER_00: I mean, this road was built 50 plus years ago, right?
• 16:43
  SPEAKER_00: And this pass, and it's been it's been a good one.
• 16:46
  SPEAKER_00: I mean, it's it's lasted a long time, surprisingly, given the terrain it's going through.
• 16:51
  SPEAKER_00: I mean, it's pretty impressive that, you know, 50 some odd years ago, or maybe even more now, that engineering was such that something could be constructed in a stable way.
• 16:59
  SPEAKER_00: I mean, as frequently as we see and hear about landslides, and we'll come back to this, like you pointed out, the southern Tetons landslides are everywhere.
• 17:07
  SPEAKER_00: I'm kind of impressed that a road lasted as long as it has without sliding away with some events, right?
• 17:13
  SPEAKER_00: You have to learn from these past episodes.
• 17:15
  SPEAKER_00: I don't know if they're mistakes or not, but of past events, right, to plan for the future.
• 17:20
  SPEAKER_00: So that's a really nice way to do it, I think, is to watch all these examples.
• 17:23
  SPEAKER_00: And and watching them is just such a visual thing.
• 17:26
  SPEAKER_00: It's just they're so visually astonishing when you see millions of tons of material flowing downhill.
• 17:34
  SPEAKER_00: It's crazy.
• 17:35
  SPEAKER_02: Yeah, it's a fun thing to teach because it's so gripping that way.
• 17:39
  SPEAKER_02: It's as visual as you can get.
• 17:41
  SPEAKER_02: And so I just use these then as mental cues and we break them down and talk about them.
• 17:45
  SPEAKER_02: And I love it.
• 17:46
  SPEAKER_02: I don't know, it's just so much fun for me.
• 17:48
  SPEAKER_02: It's one of my favorite things to teach, which I don't know if that's surprising for you or not.
• 17:52
  SPEAKER_02: But you know, when you look at these, they have common denominators though.
• 17:56
  SPEAKER_02: And so let's talk about the role of water in mass wasting events in slides and flows and creep and all of they've the role of water is undeniable.
• 18:07
  SPEAKER_02: And I break it down and I say, well, water does three things.
• 18:11
  SPEAKER_02: When you add water to rock, or when you add water to soil, or when you add water to fill, like the big fill here, what happens?
• 18:18
  SPEAKER_02: Well, water makes whatever it's saturating, whatever it is filling the pore spaces in, it makes the sediment lose its cohesion.
• 18:29
  SPEAKER_02: If you think about like a just a pile of sand, those grains are in contact with each other.
• 18:34
  SPEAKER_02: But when you uh add water to that and it fills in the pore spaces, any kind of jiggling motion at all is gonna cause water to get in between the grains, they lose their cohesion and they become slippery then.
• 18:47
  SPEAKER_02: Water makes sediment heavy.
• 18:49
  SPEAKER_02: That's another thing.
• 18:50
  SPEAKER_02: You think about like the building of retaining walls.
• 18:52
  SPEAKER_02: This is you know, retaining wall 101 is you have to give the water behind the wall a place to go because if you don't, water's gonna collect behind your retaining wall and it's gonna cause it to tilt because water's heavy, really heavy.
• 19:08
  SPEAKER_02: So that's number two.
• 19:09
  SPEAKER_02: And then the third thing is water makes my nemesis clay, it makes it slippery.
• 19:18
  SPEAKER_00: So those are the the three the three things clay, it's just so fun to bring up clay when clay comes into the picture.
• 19:27
  SPEAKER_00: Yeah, yeah.
• 19:28
  SPEAKER_02: So those are the three things that the what I just summarize as hey, this is the role of water in mass wasting.
• 19:34
  SPEAKER_00: Totally.
• 19:35
  SPEAKER_00: And the role of water is obviously a massive one.
• 19:38
  SPEAKER_00: I think that's pretty clear.
• 19:39
  SPEAKER_00: You've laid it out perfectly.
• 19:41
  SPEAKER_00: There are obviously other things that can affect or trigger a landslide, and I think one obvious one is like any kind of shaking, any kind of ground shaking, yeah.
• 19:50
  SPEAKER_00: Earthquakes, we'll talk about that.
• 19:52
  SPEAKER_00: Volcanoes erupting that are also shaking the ground, right?
• 19:56
  SPEAKER_00: Or changing the distribution of soil.
• 19:58
  SPEAKER_00: I think the other thing that we should talk about here is the human impact or the human drivers of landslides, because we can do or and we do do as humans a lot to induce landslides in some way.
• 20:12
  SPEAKER_00: So deforestation, we talked briefly about that.
• 20:15
  SPEAKER_00: This one for me is one that really stands out in my mind because when um we were growing up, we always would go to this lake in northern Michigan, and there's a big hill on the other side of the lake.
• 20:24
  SPEAKER_00: Michigan's very forested, has this old growth forest, and so it was always forested.
• 20:28
  SPEAKER_00: Then somebody started building a house there, and so they cut some of the trees down, sort of built a flat plateau up and and were going to build their house there.
• 20:37
  SPEAKER_00: And then above where the house was, where they cut down a bunch of trees, a big slump formed and a landslide formed.
• 20:44
  SPEAKER_00: I don't know if it happened very quickly or if it slumped over the course of a season or a year or something, but you could see this big scar on the landscape that was the sort of bowl-shaped depression of what's called a rotational landslide, where you get that the land kind of scoops downward and slumps downward with this curved plane behind it.
• 21:02
  SPEAKER_00: Looks like somebody took a tractor, just took a big gouge out of the hill, basically.
• 21:06
  SPEAKER_00: Looks like Crisple Heiss got on his tractor and was gouging at the hill with the shovel there.
• 21:12
  SPEAKER_00: Um, but deforestation is a really important one, obviously.
• 21:16
  SPEAKER_00: Blasting, mining, any kind of altering of landscape with building a road somewhere, we can create an unstable slope over long time scales.
• 21:25
  SPEAKER_02: Yeah, that's right.
• 21:26
  SPEAKER_02: And we do this all the time too, with building roads and you know, developments and things, which is over steepened slopes.
• 21:33
  SPEAKER_02: Whenever you have a steep slope, you're gonna have an area that's could very well be prone to mass wasting kind of events.
• 21:41
  SPEAKER_02: So over steepening of slopes.
• 21:42
  SPEAKER_02: And we call it in geology, we call that the angle of repose, the steepest angle that that slope can remain stable.
• 21:50
  SPEAKER_02: And when you go beyond that, it's going to slough, it's gonna slump, it's gonna move to become more stable.
• 21:57
  SPEAKER_02: Right.
• 21:57
  SPEAKER_02: That's another human kind of impact thing.
• 22:00
  SPEAKER_02: That happens a lot.
• 22:01
  SPEAKER_02: Yeah.
• 22:02
  SPEAKER_00: Can I maybe throw some statistics in here, which I found which were quite interesting, Chris?
• 22:05
  SPEAKER_00: Yeah.
• 22:06
  SPEAKER_00: So I found a report on the frequency and the causes of significant landslides.
• 22:10
  SPEAKER_00: Now, significant, quote unquote.
• 22:12
  SPEAKER_00: That's a squishy definition, right?
• 22:13
  SPEAKER_00: But it's estimated that between 1980 and 2018, there were over 15 million rainfall-triggered landslides.
• 22:23
  SPEAKER_00: Significant rainfall-triggered landslides around the world.
• 22:26
  SPEAKER_00: That's about 400,000 per year of rainfall triggered.
• 22:30
  SPEAKER_00: So that's water, as we've talked about, right?
• 22:32
  SPEAKER_00: That's water.
• 22:33
  SPEAKER_00: If you look at the landslide like hazard map globally, it's where there's high mountains.
• 22:37
  SPEAKER_00: That's where it gets really red and lots of landslides, but also mountains and wet, lots of rain, humid tropical climates with a lot of rain because the weathering is so much more.
• 22:47
  SPEAKER_00: You've got soil there, all those things go into it.
• 22:50
  SPEAKER_00: The average annual number of earthquake-triggered landslides, significant earthquake-triggered landslides, is around 130,000 per year.
• 22:59
  SPEAKER_00: So 400,000 rainfall-based ones to 130,000 earthquake-triggered landslides.
• 23:04
  SPEAKER_00: Okay, Chris, question for you.
• 23:06
  SPEAKER_00: Is that more or less than you would have thought?
• 23:08
  SPEAKER_02: Shockingly more.
• 23:10
  SPEAKER_02: Earthquake ones, especially.
• 23:12
  SPEAKER_02: That's exactly what I thought.
• 23:13
  SPEAKER_00: First of all, I thought the numbers are astonishingly high.
• 23:16
  SPEAKER_00: 400,000 per year of significant ones was I thought that was crazy.
• 23:21
  SPEAKER_00: I would have never guessed anything in the hundreds of thousands per year.
• 23:25
  SPEAKER_00: I would have guessed, you know, 10,000, 40,000 or something.
• 23:28
  SPEAKER_00: But then I'm I'm with you.
• 23:29
  SPEAKER_00: I would have thought there would be way more rainfall ones than earthquake ones, not like four to one ratio around about there.
• 23:36
  SPEAKER_02: Jesse, two things popped into my head as you were talking about this.
• 23:39
  SPEAKER_02: One is, you know, you and I were from southwest Michigan and we have the spectacular dunes.
• 23:45
  SPEAKER_00: Very cool, dude.
• 23:46
  SPEAKER_02: And they're big.
• 23:46
  SPEAKER_02: These are big, big dunes.
• 23:48
  SPEAKER_02: They're big and they're steep.
• 23:50
  SPEAKER_02: And so I I spend actually a lot of time, a lot of the stuff that I show my students, the images and videos from mass wasting, is along the shorelines of Lake Michigan because I want them to look at things a little bit differently.
• 24:04
  SPEAKER_02: When you can see the scarves from recent movements that have happened on these dunes.
• 24:11
  SPEAKER_02: If you think about it, how does a sand dune become oversteepened along the lake shore?
• 24:16
  SPEAKER_02: Right, right, right.
• 24:17
  SPEAKER_02: Well, if you have high lake levels and then throw in a couple really doozy storms so the waves are crashing into the base of the dunes and washing that sand back out into the lake, it just undercut the base of the dune, and then you have these homes on top of it, right?
• 24:35
  SPEAKER_02: And so the homes, well, what are the homes doing?
• 24:38
  SPEAKER_02: One, sweating, you know, they're nervous about it.
• 24:42
  SPEAKER_02: They're going, what it's constantly on their mind.
• 24:44
  SPEAKER_02: And the other thing is, though, is that the homes add weight to the dune.
• 24:49
  SPEAKER_02: So again, that's another trigger to mass wasting is the addition of weight.
• 24:53
  SPEAKER_02: So mass wasting to me, Jesse, is this just fascinating interaction between geology and humanity.
• 25:01
  SPEAKER_00: Totally.
• 25:02
  SPEAKER_00: It's totally, and you know, it's where the rubber meets the road.
• 25:04
  SPEAKER_00: These are the things you have to think about if you're building a house, especially now.
• 25:09
  SPEAKER_00: I mean, you just you see these reports from the Carolinas all the time about how homes are being swept into the ocean because of you know increased storm activity, or they're just building it on a cliff, an unstable cliff.
• 25:19
  SPEAKER_00: And a lot of these buildings go back many years before we really understood the full repercussions of landslides and erosion and maybe increased erosion because of climate change.
• 25:30
  SPEAKER_00: So I I totally agree with you.
• 25:31
  SPEAKER_00: It's such an amazing thing to teach and to focus on and to think about because it's so impactful and so dead obvious right in front of your eyes.
• 25:40
  SPEAKER_02: I have a question for you, Jesse.
• 25:42
  SPEAKER_02: What do you think the homeowners are doing to slow the process down?
• 25:47
  SPEAKER_02: I mean, these are really big, expensive, these people have money.
• 25:53
  SPEAKER_00: And I've seen Chris, the ones I've seen up in no the northern part of western Michigan there, put big boulders right against the the the hill slope there, big huge boulders to kind of prevent the wave action from eating away at the dune.
• 26:08
  SPEAKER_00: Because I mean dunes are very unstable.
• 26:10
  SPEAKER_00: So if you get to the angle of repose with a dune, it's gonna erode all the way up to the dune face, right?
• 26:14
  SPEAKER_00: So all the way up.
• 26:15
  SPEAKER_00: You can't undercut a dune.
• 26:17
  SPEAKER_00: Um I've seen that.
• 26:18
  SPEAKER_00: I've also seen big concrete pilings going down below lake level, kind of oh like a seawall?
• 26:23
  SPEAKER_00: Or like built into the into the dune to kind of help stabilize the dune a bit.
• 26:28
  SPEAKER_00: Uh I don't know what what have you seen.
• 26:30
  SPEAKER_02: So, Jesse, how how do they get those big because they're big boulders at the base of the dune?
• 26:35
  SPEAKER_02: Do you have an idea on how that process plays out?
• 26:39
  SPEAKER_00: It can't be that they chuck them down the hill, is it?
• 26:43
  SPEAKER_00: It's not.
• 26:44
  SPEAKER_02: It's not they come in with these barges.
• 26:46
  SPEAKER_02: Oh, really?
• 26:47
  SPEAKER_02: They'll float a barge right up to the shore with a crane on it and just offload these big boulders.
• 26:53
  SPEAKER_02: Yeah, that's so funny.
• 26:54
  SPEAKER_02: And then so, Jesse, real quick then, what why?
• 26:57
  SPEAKER_02: What do the boulders do?
• 26:58
  SPEAKER_02: How does this stabilize the base of the slope?
• 27:00
  SPEAKER_00: Yeah, so a lot of the erosional activity will take place in the winter months, typically storm or the storm months.
• 27:05
  SPEAKER_00: Fall is a good one for storms on that part of Lake Michigan.
• 27:08
  SPEAKER_00: And so basically what the big boulders are doing is they're just dissipating big storm wave energy from hitting the cliff face.
• 27:15
  SPEAKER_00: So if you go there on a calm day, you can see there's no erosion happening because the beach and the water levels are quite far away from that dune slope, but the storms are really what eats away.
• 27:26
  SPEAKER_00: Big storm waves come crashing in.
• 27:27
  SPEAKER_00: So it's like uh any kind of seawall mitigation measure where it's just dissipating the storm energy.
• 27:33
  SPEAKER_00: The storm waves.
• 27:34
  SPEAKER_02: Yeah, it's taking the energy away.
• 27:35
  SPEAKER_02: That's right.
• 27:36
  SPEAKER_02: You got it.
• 27:36
  SPEAKER_02: Jesse, one other thing before we transition into just mentioning briefly two famous, you know, mass-wasting events in the Teton region.
• 27:46
  SPEAKER_02: The other thing that I want to talk about that I focus on from a pedagogical standpoint with my students is paying attention to the slope of the sedimentary rocks.
• 27:58
  SPEAKER_02: Are they dipping in the same direction that the slope of the land is going?
• 28:02
  SPEAKER_02: That's another really important consideration.
• 28:05
  SPEAKER_02: And also the kind of angle at which the foliation, if you're dealing with metamorphic rocks, if they're foliated, that's parallel to the direction of the slope, too.
• 28:16
  SPEAKER_02: Those are things that you don't want to have a house at the base of that, or you don't want to have you know put a road at the base of that kind of thing.
• 28:24
  SPEAKER_02: So those are just that's another trigger, it's another player in this whole mass wasting kind of topic.
• 28:30
  SPEAKER_00: Totally, totally.
• 28:30
  SPEAKER_00: I think that's a really important one, Chris.
• 28:32
  SPEAKER_00: And and before we transition, well, let's transition now to we're gonna focus on a couple of landslides that have happened in the Teton region, one of which we talk about in our Grand Teton National Park audiobook, which is available on the CamTeo app.
• 28:45
  SPEAKER_00: If you go to the first link in your show notes, you can download the app and get access to a bunch of stuff and you'll see some cool images of these because it's pretty hard to show you images with a podcast here.
• 28:54
  SPEAKER_00: But if you go to that, you'll get some cool images that show one of them, the Grovaunt slide.
• 28:58
  SPEAKER_00: But Chris, I want to just mention talking about the structure, we're gonna talk about this more with the with the Groveant slide, but I saw the Frank slide, which is one of the largest landslides in North America.
• 29:08
  SPEAKER_00: It might even be the largest.
• 29:10
  SPEAKER_00: I can't remember now.
• 29:10
  SPEAKER_00: I saw it in grad school.
• 29:11
  SPEAKER_00: It's in Alberta, but the entire mountain is an anticline.
• 29:15
  SPEAKER_00: So the mountain was an anticline, and it really the sort of mountain faces.
• 29:20
  SPEAKER_02: Jesse, can you real quick define what an anticline is?
• 29:23
  SPEAKER_00: Yeah, so an anticline is take rocks and fold them, fold the edges down so that it looks like an A.
• 29:28
  SPEAKER_00: I always think anticline looks like an A.
• 29:30
  SPEAKER_00: And so you you take two pieces of paper.
• 29:33
  SPEAKER_00: Yeah.
• 29:34
  SPEAKER_00: And you fold the paper down, it's a it's a upside down U or an A.
• 29:38
  SPEAKER_00: So this mountain was an anticline.
• 29:41
  SPEAKER_00: So both sides of the mountain actually had what we call unstable slopes because the slope was paralleling the sedimentary layering, and sedimentary layering as a weak layer.
• 29:51
  SPEAKER_00: And so one entire side of the mountain fell off.
• 29:54
  SPEAKER_00: It was limestone on top, so the limestone's a cliff former and kind of hung on and formed some steep cliffs, and then eventually it gave way.
• 30:01
  SPEAKER_00: But it was a huge landslide, kind of really devastating, pretty tragic loss of life there, too.
• 30:07
  SPEAKER_00: Kind of decimated the town of Frank.
• 30:08
  SPEAKER_00: But um, anyway, this is Turtle Mountain, has this anticlinal structure to it.
• 30:13
  SPEAKER_00: So this is not unlike the Tetons, which we're gonna talk about.
• 30:17
  SPEAKER_00: What are the two, Chris?
• 30:18
  SPEAKER_00: Because you showed me, I think, if I remember correctly, on Summer Signs when I went there.
• 30:24
  SPEAKER_00: We went to the Hebgen Lake, Quake Lake.
• 30:27
  SPEAKER_00: Is that correct?
• 30:28
  SPEAKER_00: We went there, right?
• 30:28
  SPEAKER_02: Yeah, we did.
• 30:29
  SPEAKER_02: We did.
• 30:30
  SPEAKER_02: I took you there.
• 30:30
  SPEAKER_02: I don't go there anymore.
• 30:32
  SPEAKER_00: You don't, okay.
• 30:33
  SPEAKER_02: I don't, yeah.
• 30:34
  SPEAKER_02: But it's a beautiful area and the geology is amazing.
• 30:37
  SPEAKER_02: I just I have to pick and choose, Jesse.
• 30:40
  SPEAKER_00: I'm at the stage of my life when so that one felt so what is the quick and dirty geology of Quake Lake?
• 30:48
  SPEAKER_00: Yeah, I think that probably gives it away a little bit, but but what what is it?
• 30:51
  SPEAKER_00: Yeah and and why is it important?
• 30:53
  SPEAKER_02: It's a beautiful valley where this happened.
• 30:56
  SPEAKER_02: So actually, this is just northwest of Yellowstone National Park.
• 31:00
  SPEAKER_02: At 1137 at night, a 7.5 earthquake happened.
• 31:04
  SPEAKER_02: It was actually a massive well, Jesse, it's a normal fault that ripped through this valley and the displacement was in places at 20 feet, which is amazing.
• 31:16
  SPEAKER_02: That's a lot of movement that happened in just a really a matter of seconds.
• 31:20
  SPEAKER_02: Anyway, that violent shaking caused the mountainside, which was steep.
• 31:26
  SPEAKER_02: I mean, we talked about the angle of repose.
• 31:28
  SPEAKER_02: I mean, this was not stable, but that shaking just dislodged the whole mountainside and it slid down and it dammed the Madison River.
• 31:37
  SPEAKER_02: And then you have Quake Lake, which is the lake that formed behind now the earthen dam that was blocking the Madison River, and it rose rapidly.
• 31:47
  SPEAKER_02: This was a this was a national event.
• 31:49
  SPEAKER_02: I mean, they brought in smote jumpers and hotshots and all these people that are used to fighting forest fires, they dropped them in to do rescue because people were trapped, people were climbing trees to escape the the rising water.
• 32:03
  SPEAKER_02: You know, another thing really that is just amazing about this earthquake is when that mountainside came down, that mass waste and event, it fell and it pushed air out from underneath the rock.
• 32:16
  SPEAKER_02: And it was hurricane force air, toppled trailers because it there were campgrounds all up and down the valley, and just the stories from from this are they're really amazing.
• 32:27
  SPEAKER_02: It's a compelling place to go.
• 32:29
  SPEAKER_02: There are still a number of people that are buried beneath where the slide happened where it crossed the Madison River.
• 32:36
  SPEAKER_00: Chris, two quick things about this is that I mean, we're talking about a massive landslide that created a lake that is up to 100-120 feet deep behind it.
• 32:45
  SPEAKER_00: So this is a big landslide that filled up a valley, filled up the valley with debris and dammed, as you said, the Madison River.
• 32:51
  SPEAKER_00: So this is no small event, it's no small lake.
• 32:54
  SPEAKER_00: Now there's mitigation, you know, there's a spillway over the earth and dam and all this kind of stuff to kind of prevent it breaking through, which we'll talk about the Grove on slide next.
• 33:03
  SPEAKER_00: Uh, but the other thing is that that's a c what you talked about about the air thing, the the air kind of flowing out from underneath this.
• 33:10
  SPEAKER_00: When we get really rapid rock falls or landslides, and really they're more common with falls or things that are happening really rapidly, they kind of ride on a cushion of air because the air cannot escape out from underneath of the mass that's moving downhill quick enough.
• 33:27
  SPEAKER_00: So they end up kind of riding on this cushion of air, compressed air that can't escape as quickly.
• 33:32
  SPEAKER_00: And so they end up accelerating downslope.
• 33:35
  SPEAKER_00: And this can be really, really rapid because of this process, the how quickly this can happen.
• 33:40
  SPEAKER_02: You, Jesse, you and I have talked about this before in Yosemite National Park, we have rockfall events that are very, very common.
• 33:48
  SPEAKER_02: These massive slabs break off these walls, and the air that gets shoved out from underneath this crashing rock will snap off these giant redwoods.
• 33:58
  SPEAKER_02: It's crazy.
• 33:59
  SPEAKER_02: Amazing, uh unbelievable force of the city.
• 34:03
  SPEAKER_00: That is a repercussion of mass wasting that I do not think is obvious at all that it would happen.
• 34:10
  SPEAKER_00: You just do not think that this is so much material, so much mass that's falling so quickly that literally the air underneath of it cannot escape.
• 34:19
  SPEAKER_00: So it creates a cushion of compressed air.
• 34:21
  SPEAKER_00: That is just something that we have to highlight because that's not obvious and it speaks to the power of these things.
• 34:26
  SPEAKER_02: It's I agree, Jesse, but you said something, but you just glossed over it, and I want to double-click on it because it's riding on a cushion of air, which is a positive feedback loop because it makes this thing then move much faster than it should be able to move.
• 34:42
  SPEAKER_02: If it weren't riding on a cushion of air, it would it would be a much slower movement.
• 34:46
  SPEAKER_02: That's right.
• 34:47
  SPEAKER_02: This thing, these falls as they crash down into the valleys below, they're moving really, really fast.
• 34:54
  SPEAKER_02: And it's because of the air that they're riding on essentially and pushing out from underneath them.
• 34:59
  SPEAKER_00: It's just it's an amazing feature and a traumatic and devastating feature of these things.
• 35:04
  SPEAKER_00: So, Chris, um, speaking of earth and dams, the Grovan slide, which we have.
• 35:12
  SPEAKER_00: G-R-O-W uh Yes Ventre.
• 35:17
  SPEAKER_00: This this is G-R-O-S space, capital V E-N-T-R-E, Grovante.
• 35:22
  SPEAKER_00: This is a landslide that Chris you'll tell the story of.
• 35:26
  SPEAKER_00: But we we have a whole chapter on this in our Grand Teton audiobook with cool images to show you where it is in the Grand Teton area in the Jackson Hole area, but it's a really cool story.
• 35:34
  SPEAKER_00: Chris, what's the short version of the story?
• 35:36
  SPEAKER_00: Because it's the earth and dam thing that we talked about before, except there's there's some other events that happen, right?
• 35:42
  SPEAKER_02: Yeah, I just want to make sure everybody understands that where this slide happened in the Grovant Range, the Grovaunt Range is just east of the Tetons.
• 35:52
  SPEAKER_02: So you have Jackson Hole, the valley.
• 35:55
  SPEAKER_02: The Tetons are on one side and the Grovan Range is on the other side.
• 35:58
  SPEAKER_02: So where the slide happened is in a beautiful, beautiful area.
• 36:01
  SPEAKER_02: And so the you know, the short of it is is that this rancher, he kind of knew something was not stable with his ranch.
• 36:09
  SPEAKER_02: You know, he heard noises and he heard water, and and so he kind of suspected that something was gonna happen.
• 36:15
  SPEAKER_02: So he just sold it.
• 36:16
  SPEAKER_02: Yeah.
• 36:17
  SPEAKER_02: And you know, so somebody bought it, and you know, a couple of years later, the guy was right, you know, it it gave way and slid down into the Grovant River and it dammed it.
• 36:29
  SPEAKER_02: And same thing, a massive lake behind the earthen dam now.
• 36:33
  SPEAKER_02: And this was just uh a really, really tragic.
• 36:38
  SPEAKER_02: People lost their lives, people lost their homes and their livelihood.
• 36:42
  SPEAKER_02: But this was you said that the Frank slide was the biggest in North America.
• 36:47
  SPEAKER_02: This one was the biggest in the United States history, right here.
• 36:51
  SPEAKER_02: So it's a lot, it's uh it's a lot.
• 36:54
  SPEAKER_00: It's a lot, yeah.
• 36:54
  SPEAKER_00: Eventually the earth and dam gave way and then obviously sort of flood downstream because of that.
• 37:00
  SPEAKER_00: So very different, but I want to come back to the reason why, right, Chris.
• 37:04
  SPEAKER_00: You talked at the beginning that there's different mechanisms for landslides that we're gonna talk about, and the Grovaunt one is again, water's involved, water's certainly involved here, because the rocks are sloped downhill, if that makes sense.
• 37:19
  SPEAKER_00: So the rock layers are tilted at sort of a similar angle as the hill slope, which means that it's quite easy for a big block to slide downhill.
• 37:30
  SPEAKER_00: And that's the same thing as the Frank slide, where you have rock layers that are tilted down slope.
• 37:35
  SPEAKER_00: That makes for a really weak layer, a weak layer that is gravitationally unstable, and it can slide down into a valley very easily.
• 37:44
  SPEAKER_00: So the Grovant and the Frank slide, that's what was going on.
• 37:47
  SPEAKER_00: Hebgen Lake or Quake Lake, that was an earthquake that triggered that landslide, right, Chris?
• 37:52
  SPEAKER_00: So different phenomenon, different structural implications or different structural setups to the different landslides here.
• 38:00
  SPEAKER_00: But Chris, you say this frequently that, like, you know, the the Tetons are just spectacular muscular mountains, and they're the youngest mountains, and they're beautiful.
• 38:08
  SPEAKER_00: And that means they're active in the erosional sense as well, right?
• 38:12
  SPEAKER_00: That that means that they are eroding, actively eroding in front of us sometimes.
• 38:17
  SPEAKER_00: And this is one instance where that is that's the case.
• 38:20
  SPEAKER_00: It's it's ongoing.
• 38:21
  SPEAKER_00: We can see erosion happening sometimes slowly, sometimes catastrophically.
• 38:26
  SPEAKER_02: That's right.
• 38:26
  SPEAKER_02: And you can see the scarp from the Grovan slides almost a hundred years ago now, and that scar on the land, it's hard to miss.
• 38:35
  SPEAKER_00: It's obvious.
• 38:35
  SPEAKER_00: It's obvious from you know satellite imagery, even you pulled a nice Google Earth image uh for for the audiobook here, and it's just a totally cool one.
• 38:43
  SPEAKER_00: So, Chris, just to end on, this is a very active, tectonically active region, the Tetons.
• 38:48
  SPEAKER_00: So there's been a lot of proposals coming back to the big fill landslide and the Teton Pass.
• 38:53
  SPEAKER_00: You know, how how do we not have this happen again?
• 38:55
  SPEAKER_00: There have been proposals for tunnels or bridges.
• 38:58
  SPEAKER_00: There was actually a bridge that was built almost finished, and then in 1970 it was taken out by a rockfall that it was engineered to not be taken out by, but a big rockfall came in and took out the bridge.
• 39:09
  SPEAKER_00: So that's a concern, that's a going concern in all of these areas.
• 39:12
  SPEAKER_00: Tunnels are ridiculously expensive.
• 39:15
  SPEAKER_00: I saw an estimate for a billion dollars plus half a million dollars a year in upkeep for a tunnel in the Teton Pass, which I live in in Pennsylvania, and there's there's a lot of tunnels through the Appalachians, but they were built actually in the railroad era.
• 39:28
  SPEAKER_00: So they were built for railroads, and now we put highways through them.
• 39:31
  SPEAKER_00: And when Eisenhower was putting the highways in place, they used a lot of those railroad tunnels from the sort of robber baron industrialist era.
• 39:38
  SPEAKER_00: So tunnels are a bit impractical uh potentially there in the Tetons, or at least at the moment, prohibitively expensive.
• 39:45
  SPEAKER_00: So it's just a really interesting area, Chris.
• 39:47
  SPEAKER_00: And I look forward to seeing this map of the landslides in the southern Tetons.
• 39:50
  SPEAKER_00: You've got to ping me that when we get off recording.
• 39:52
  SPEAKER_02: I gotcha.
• 39:53
  SPEAKER_02: I will for sure.
• 39:55
  SPEAKER_00: Um one thing to end on, Chris.
• 39:57
  SPEAKER_00: I uh you probably saw this too.
• 39:59
  SPEAKER_00: There's an interview with the Wyoming Department of Transportation's chief geologist, James Dahill, and he had a quote that I just it made me think of Chris Bullheis.
• 40:07
  SPEAKER_00: His quote is erosion never stops, just like gravity never stops.
• 40:12
  SPEAKER_00: I thought that was a great quote.
• 40:14
  SPEAKER_00: I just thought of you, man.
• 40:15
  SPEAKER_00: I thought this is something Chris Bull Ice will love.
• 40:18
  SPEAKER_02: I thought of myself too when I read it.
• 40:22
  SPEAKER_02: That's pretty good.
• 40:24
  SPEAKER_02: I'm like, that sounds like something I would say, right there.
• 40:26
  SPEAKER_02: It does, it does.
• 40:27
  SPEAKER_02: That does erosion happens.
• 40:29
  SPEAKER_00: Erosion happens, man.
• 40:31
  SPEAKER_00: Erosion never stops, just like gravity never stops.
• 40:34
  SPEAKER_00: Man, if that isn't a Chris Bullism, and you know what?
• 40:36
  SPEAKER_00: You're probably gonna swipe that and you're gonna start using it in class, and then every student from 2024 onwards is gonna think that's a Chris Bullheism.
• 40:44
  SPEAKER_02: That's absolutely they're not gonna know who Dahill is, they're gonna know Chris Bullheis said this a long time ago.
• 40:53
  SPEAKER_00: You know what, Jesse?
• 40:54
  SPEAKER_02: I know what my skills are, and my skills are recognizing good things, and then I steal them.
• 40:58
  SPEAKER_02: That's perfect.
• 40:59
  SPEAKER_02: So, you know, we all gotta be good at something.
• 41:01
  SPEAKER_00: It doesn't, man.
• 41:02
  SPEAKER_00: Uh well, this was uh it turns out to be a little bit longer episode than we were originally planning on.
• 41:06
  SPEAKER_00: But it's interesting, it's fun, it's timely, and good news is the Big Phil landslide was not tragic, uh at least immediately tragic, although it's disrupted a lot of people's commutes and lives and daily lives that uh nobody lost their life in the event.
• 41:21
  SPEAKER_00: So um that's right.
• 41:22
  SPEAKER_02: And that's well, hey, shout out to Ron.
• 41:25
  SPEAKER_02: Yeah, thanks for the thanks for the listener question.
• 41:27
  SPEAKER_00: The great question, the great nudge in this direction.
• 41:29
  SPEAKER_00: It's been awesome.
• 41:30
  SPEAKER_00: Yeah.
• 41:30
  SPEAKER_00: So that's a wrap.
• 41:31
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• 41:33
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• 41:35
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• 41:36
  SPEAKER_00: We always appreciate that.
• 41:38
  SPEAKER_00: You can also download our app, the Camp Geo app.
• 41:40
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• 41:44
  SPEAKER_00: You can download it on your mobile device.
• 41:46
  SPEAKER_00: We have a lot of audiobooks for sale there.
• 41:48
  SPEAKER_00: We also have a ton of free content.
• 41:50
  SPEAKER_00: Basically, the introduction to geology of the class that Chris teaches at the high school level, and I teach at the college level, is there with all sorts of images and the geology of the grand T content we just talked about is also available for sale right now.
• 42:03
  SPEAKER_00: Send us an email for geopath at gmail.com and you can follow us on all the social media at