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Red River Gorge, Kentucky · PlanetGeo: The Geology Podcast

• 0:03
  SPEAKER_00: Welcome to Planet Geo, the podcast where we talk about our amazing planet, how it works, and why it matters to you.
• 0:14
  SPEAKER_00: Christopher Bullheis.
• 0:16
  SPEAKER_00: Hey.
• 0:17
  SPEAKER_00: How are you doing, Jesse?
• 0:19
  SPEAKER_00: Hey.
• 0:19
  SPEAKER_00: Happy Jesse.
• 0:20
  SPEAKER_00: Happy Jesse's here today.
• 0:22
  SPEAKER_01: Oh, yes.
• 0:22
  SPEAKER_01: Everybody, we get happy Jesse.
• 0:24
  SPEAKER_01: It's a good Jesse.
• 0:25
  SPEAKER_01: He's the fun guy.
• 0:26
  SPEAKER_00: I've got my fun pants on today.
• 0:28
  SPEAKER_00: It's good.
• 0:28
  SPEAKER_00: Good.
• 0:29
  SPEAKER_00: Good for you.
• 0:29
  SPEAKER_00: I'm happy about that.
• 0:31
  SPEAKER_00: So let's let's just dive right in here.
• 0:33
  SPEAKER_00: But before we do quick introductions, you're Chris Bullheis.
• 0:36
  SPEAKER_00: I'm Jesse Rymink.
• 0:38
  SPEAKER_00: You are mentor.
• 0:39
  SPEAKER_00: I'm mentee in this relationship.
• 0:42
  SPEAKER_00: You're a former high school teacher, uh, high school teacher in Huttsville Public Schools in Michigan.
• 0:48
  SPEAKER_00: You have won many teaching awards at the national and regional level.
• 0:52
  SPEAKER_00: You teach a field geology course.
• 0:53
  SPEAKER_00: You taught me the basics of geology and all the things that we're going to kind of cover today.
• 0:58
  SPEAKER_00: Most of them I first saw under your tutelage.
• 1:00
  SPEAKER_01: That's right.
• 1:00
  SPEAKER_01: And you are Dr.
• 1:01
  SPEAKER_01: Jesse Rymink.
• 1:02
  SPEAKER_01: You're one of the best students I ever had, and I'll say that.
• 1:05
  SPEAKER_01: I've gone on record.
• 1:06
  SPEAKER_01: I know.
• 1:07
  SPEAKER_01: I've gone on record saying that too many times.
• 1:08
  SPEAKER_01: It makes me feel bad.
• 1:09
  SPEAKER_00: But I'm starting to get a big head over here if you keep saying that.
• 1:13
  SPEAKER_01: And you went on and got your PhD in geoscience.
• 1:16
  SPEAKER_01: You got it at the University of Alberta up in Canada.
• 1:18
  SPEAKER_01: And now you work at one of the most prestigious geoscience schools in the country at Penn State.
• 1:23
  SPEAKER_01: And that's awesome.
• 1:24
  SPEAKER_00: We are Penn State.
• 1:25
  SPEAKER_00: And we are Planet Geo.
• 1:27
  SPEAKER_00: And this is Planet Geo.
• 1:28
  SPEAKER_00: Let's uh I don't know.
• 1:29
  SPEAKER_00: We talk about a lot of cool stuff.
• 1:31
  SPEAKER_00: We like to talk about locations as well.
• 1:32
  SPEAKER_00: This is one of them.
• 1:33
  SPEAKER_00: And Chris, this is going to be, I've never been there.
• 1:36
  SPEAKER_00: I've never been to the Red River Gorge.
• 1:38
  SPEAKER_00: I live in the Appalachians now.
• 1:39
  SPEAKER_00: And so the regional geology is kind of similar, but you're the expert here.
• 1:43
  SPEAKER_00: You've been there.
• 1:44
  SPEAKER_00: I think you guys have gone on climbing trips, right?
• 1:45
  SPEAKER_00: To the Red River Gorge, you and your family?
• 1:47
  SPEAKER_01: Um, no, we haven't.
• 1:49
  SPEAKER_01: No, we haven't actually.
• 1:50
  SPEAKER_01: Um, we talked about it.
• 1:51
  SPEAKER_01: My son is it really into climbing a lot.
• 1:54
  SPEAKER_01: He's quite good.
• 1:55
  SPEAKER_01: And the last time we were there, which was in December, we had this like discussion about whether he was gonna bring all of his gear.
• 2:01
  SPEAKER_01: He's got a big trunk of gear, and sure, as you do didn't make the cut.
• 2:05
  SPEAKER_01: Yeah.
• 2:06
  SPEAKER_01: So anyway, this is this episode, Jesse.
• 2:10
  SPEAKER_01: This is a public service podcast right here today.
• 2:13
  SPEAKER_01: Because I am in love with Red River Gorge.
• 2:16
  SPEAKER_01: This is it's Red River Gorge in Kentucky.
• 2:18
  SPEAKER_01: That's what we're talking about today.
• 2:20
  SPEAKER_01: We're gonna go into the geology of this amazing place.
• 2:22
  SPEAKER_01: We're gonna talk about some of the features that make this place so cool, and then we'll round off with some hiking recommendations based on my experience.
• 2:30
  SPEAKER_01: You know, it's just like this place is so cool that I want to put it out there.
• 2:34
  SPEAKER_01: You know, I live in Michigan and uh it's a seven-hour drive, which for us that's a doable thing for like even a long weekend.
• 2:42
  SPEAKER_00: Yeah, and it doesn't really have the international cachet of a place like Yellowstone or Yosemite National Park, but on the East Coast, you know, it is well known for East Coasters as like one of the climbing destinations that's within driving distance from many of the southern east coast cities in the United States.
• 2:58
  SPEAKER_00: So great place to be able to do that.
• 2:59
  SPEAKER_01: Yeah, that's right.
• 2:59
  SPEAKER_01: It is it is a climbing Mecca.
• 3:01
  SPEAKER_01: So I've never been there in the summertime, and everybody that I've spoken to about this says it is so incredibly busy during the summer.
• 3:09
  SPEAKER_00: Right.
• 3:10
  SPEAKER_01: So that's why I avoid it.
• 3:11
  SPEAKER_01: Then we go in the wintertime, and like this is something that we have just kind of as we've gotten older with my kids.
• 3:19
  SPEAKER_01: My son's in the military and my daughter's in college, and so we've kind of gone away from Christmas presents and things like that because they have everything they need, and our Christmas present to our family, to our kids, is destinations now, and this is one of the things that we love to do.
• 3:36
  SPEAKER_01: So we'll pay for everybody to get there.
• 3:39
  SPEAKER_01: We rent a house in the mountains and we just spend our time hiking and and playing board games and cooking and that kind of thing.
• 3:46
  SPEAKER_01: And Red River, man, it's just when I think of it, I get all warm and fuzzy inside because it's family.
• 3:54
  SPEAKER_00: It's yeah, it's I love it, man.
• 3:56
  SPEAKER_01: It's so cool.
• 3:57
  SPEAKER_00: That's a great spot.
• 3:58
  SPEAKER_00: So let's give a little rundown of where we're going here.
• 4:00
  SPEAKER_00: First of all, we have to talk about the Appalachian Mountains.
• 4:03
  SPEAKER_00: We have to at least give a sort of a broad summary of what happened in this area from a geologic standpoint, and that goes back several hundred million years.
• 4:13
  SPEAKER_00: We're gonna talk about how the rocks themselves that are exposed in Red River Gorge, how they were deposited, how those rocks were formed.
• 4:20
  SPEAKER_00: And then we have to talk about how did those things get above sea level?
• 4:23
  SPEAKER_00: How did they get uplifted?
• 4:24
  SPEAKER_00: How did they get eroded?
• 4:25
  SPEAKER_00: And finally, there's a couple of really amazing features: the arches and the natural bridges and the banding, this really colorful banding.
• 4:33
  SPEAKER_00: So we're gonna talk a little bit about that near the end or interject that throughout.
• 4:37
  SPEAKER_00: So, Chris, lead us off, man.
• 4:39
  SPEAKER_00: Ancestral Appalachian Mountains.
• 4:41
  SPEAKER_01: Yeah, some say Appalachia, some say Appalachia, I say Appalachia.
• 4:47
  SPEAKER_01: The Appalachians, we have to talk about this.
• 4:50
  SPEAKER_01: If you want a more detailed explanation for the geology of the Appalachians and how that all happened, go back to our Great Smoky Mountain National Park episode.
• 5:00
  SPEAKER_01: We have to talk, though, about the Appalachians and their formation here because they do relate in a more remote kind of way, but they do relate to Red River Gorge for sure.
• 5:11
  SPEAKER_01: So the bottom line is the Appalachians they began forming as Pangaea came together.
• 5:18
  SPEAKER_01: The last time there was a supercontinent, there were a lot of things going on, and it was this occurred over a to me what I think is an impressive amount of geologic time.
• 5:31
  SPEAKER_01: So we're just glossing through this, but when North America began to collide with North Africa as this supercontinent was forming, so this was a continent-to-continent convergent boundary, that's when the Appalachians began to really rise to this prominent mountain chain that is now like this north-south range in the eastern part of the United States.
• 5:57
  SPEAKER_01: When I say it's complicated, I think the one thing I want to point out is that the entire north-south range, which now goes, you know, from Alabama up through Maine and through Newfoundland and is a part of the Caledonian mountains in northern Europe, northwestern Europe, this linear chain didn't all happen at the same time.
• 6:19
  SPEAKER_01: To me, it's more like the analogy of a swinging door, as the door closes gradually.
• 6:25
  SPEAKER_01: In other words, the collision took place first in the northern part of the Appalachians, and then as the door began to close, as the continents began to collide, the central and southern part of the Appalachians began to uplift.
• 6:40
  SPEAKER_01: And so a continent-to-continent convergent boundary forms mountains like the Himalayas.
• 6:47
  SPEAKER_01: And it is widely said that in their prime, in these young, muscular mountains, the Appalachians may have been every bit as impressive as the modern-day Himalayas.
• 7:00
  SPEAKER_01: And we can determine that based on things like the amount of sediment that has been shed off from the Appalachians.
• 7:09
  SPEAKER_00: And it is a massive amount of sediment.
• 7:12
  SPEAKER_00: I mean, all of the rocks that are exposed in the physiographic features that we'll talk about, the Allegheny Mountains, the Allegheny Plateau, the Cumberland Mountains, the Cumberland Plateau, all of those rocks are formed by the shedding of the sediments.
• 7:25
  SPEAKER_00: So ancient mountain belts now deposited into sandstones and quartzites and conglomerates and shales, all that stuff is deposited there.
• 7:34
  SPEAKER_00: So we lost a massive amount of the crust, was lopped off due to erosion at this time and eventually deposited to form the rocks we see today.
• 7:42
  SPEAKER_01: So, Jesse, what happens when Pangaea comes together, the mountains have formed, and then Pangaea began to break apart?
• 7:50
  SPEAKER_01: What are the patterns that we can often see in geology when a mountain building event ceases, the uplift process ends?
• 7:58
  SPEAKER_01: What happens then?
• 7:58
  SPEAKER_01: What takes over?
• 7:59
  SPEAKER_00: Yeah, so then it's erosion.
• 8:01
  SPEAKER_00: If you don't have stuff pushing up, well, erosion's kind of always going on in the background, but as soon as you stop this uplift, then erosion is the main thing that's happening.
• 8:11
  SPEAKER_00: And so it becomes that dominant process.
• 8:14
  SPEAKER_00: Exactly.
• 8:15
  SPEAKER_00: And you end up knocking off, lopping off the top of the mountain belt by erosion and weathering and depositing that material, that mass, all those elements and minerals, somewhere else.
• 8:25
  SPEAKER_00: And that happens to be, in this case, to the west, in an inland sea or actually river delta plains as well.
• 8:32
  SPEAKER_00: So you can think of this as like a shallow sea with lots of rivers flowing into it, lots of deltas, and all that stuff is being deposited to the west.
• 8:41
  SPEAKER_00: So interior of the current-day continent.
• 8:44
  SPEAKER_00: Think of the Appalachian Mountain Belt.
• 8:45
  SPEAKER_00: That used to be much higher.
• 8:46
  SPEAKER_00: There used to be an inland sea to the west of that, and all the sediments in Pennsylvania, West Virginia, Kentucky, all the way down, were deposited in this inland sea region.
• 8:57
  SPEAKER_01: Yeah, and again, you hit it, you said it.
• 8:59
  SPEAKER_01: We're talking about massive amounts of sediment.
• 9:02
  SPEAKER_01: When we talked about the formation of the Great Smoky Mountain National Park, some of the sediment accumulations exceeded nine vertical miles.
• 9:11
  SPEAKER_01: That's a truly hard to wrap your mind around what the hell is going on here, really.
• 9:16
  SPEAKER_01: I mean, that's that's amazing.
• 9:18
  SPEAKER_01: And that's one of the things I love, love about geology is scale.
• 9:23
  SPEAKER_01: So I like numbers, right?
• 9:25
  SPEAKER_01: I like to put things in order.
• 9:27
  SPEAKER_01: So the first thing in terms of the formation of Red River Gorge is the Appalachians, this uplift, massive, important event.
• 9:34
  SPEAKER_01: Two is the end of that event, which then erosion begins to dominate, which is a carry and then sediment, like you said, to the west and depositing it in what is now the Red River Gorge.
• 9:45
  SPEAKER_01: The third thing leads us into really the heart of Red River Gorge, which is this famous sandstone layer.
• 9:56
  SPEAKER_01: Jesse, what's this sandstone layer called?
• 9:58
  SPEAKER_00: This is the Corbin sandstone.
• 10:00
  SPEAKER_00: And these things are generally massive.
• 10:03
  SPEAKER_00: And what we mean by that is relatively homogenous grain size across them, so it looks like a massive piece of rock, right?
• 10:10
  SPEAKER_00: Marbles would be massive.
• 10:11
  SPEAKER_00: It's not finely layered, it's not broken apart into a whole bunch of different little sections.
• 10:15
  SPEAKER_00: It's basically what we call a quartz aronite sandstone, which means it's very pure quartz sandstone.
• 10:21
  SPEAKER_00: There's not a lot of stuff apart from quartz in this thing.
• 10:24
  SPEAKER_00: And this layer is 323 million to about 315 million years old.
• 10:30
  SPEAKER_00: That's kind of the age of deposition of the sandstone, when those sand grains were being deposited by an ancient river system flowing to the west from the Appalachians to the west, depositing sand in really pure quartz, Aaronite sandstone.
• 10:44
  SPEAKER_01: And for our geology nerds out there that are into the geologic time scale, which that's not a derogatory comment I'm I just made there.
• 10:52
  SPEAKER_01: That's early pension.
• 10:54
  SPEAKER_01: Despite how it sounds like time that we're talking about.
• 10:56
  SPEAKER_01: But we categorize ourselves in that, right?
• 10:58
  SPEAKER_01: Like we are the biggest nerds we know.
• 11:00
  SPEAKER_01: For sure.
• 11:00
  SPEAKER_01: That's right.
• 11:01
  SPEAKER_01: This sandstone is the whole story, right?
• 11:04
  SPEAKER_01: I mean, it's the Corbin sandstone and what happens in it that makes this a climbing mecca.
• 11:10
  SPEAKER_01: It's the Corbin sandstone that has been carved into these gorges, which is, you know, hence the name Red River Gorge.
• 11:17
  SPEAKER_01: So the beauty of this place is because of the Corbin and what happened to it.
• 11:23
  SPEAKER_01: So let's get into some of that.
• 11:25
  SPEAKER_01: I think if you, for the first time, you go hiking in Red River Gorge, you're gonna, I don't care who you are, you're gonna recognize certain things.
• 11:35
  SPEAKER_01: And we're gonna talk about those things in a little bit here.
• 11:38
  SPEAKER_01: We'll get into more detail at the end of the episode in terms of what exactly happened with these.
• 11:42
  SPEAKER_01: But one of the things that anyone can see is what's called crossbedding.
• 11:48
  SPEAKER_01: It is a dominant sedimentary feature that we see in Red River Gorge.
• 11:54
  SPEAKER_01: It's beautiful, and so let's should we get into crossbeds here?
• 11:58
  SPEAKER_00: Yeah, let's do it.
• 11:59
  SPEAKER_00: And crossbedding's everywhere.
• 12:00
  SPEAKER_00: In any, well, not any, but in most sandstones of this type, like the Corbin sandstone, you're going to have massive amounts of crossbedding.
• 12:09
  SPEAKER_00: We have it here in Pennsylvania.
• 12:10
  SPEAKER_00: The ridges are usually made of quartzites.
• 12:12
  SPEAKER_00: There is crossbedding in there.
• 12:13
  SPEAKER_00: You have it in places like the Grand Canyon in the United States, where you have a super thick package of sandstones right at the top that caps the Grand Canyon.
• 12:22
  SPEAKER_00: That stuff has huge crossbeds in it too.
• 12:25
  SPEAKER_00: And so crossbedding is it's a very Can I add to that list a second?
• 12:29
  SPEAKER_01: Because you know, up in the UP in Pictured Rocks National Lakeshore, beautiful crossbedded sandstone.
• 12:35
  SPEAKER_00: UP is the upper peninsula of Michigan for those from Michigan, yeah.
• 12:40
  SPEAKER_01: Is that not widely known?
• 12:41
  SPEAKER_00: That's not widely known.
• 12:43
  SPEAKER_00: No, no.
• 12:44
  SPEAKER_01: Are you really?
• 12:44
  SPEAKER_01: Yeah.
• 12:45
  SPEAKER_01: Ah, okay.
• 12:46
  SPEAKER_01: Yep.
• 12:46
  SPEAKER_01: Um, so we call them Upers, UP, Upper Peninsula is what it refers to.
• 12:51
  SPEAKER_01: It's or the upper hand of Michigan, right?
• 12:54
  SPEAKER_01: Right, right.
• 12:54
  SPEAKER_01: Yeah.
• 12:54
  SPEAKER_01: Anyway, pictured Rocks National Lakeshore, gorgeous area.
• 12:57
  SPEAKER_01: I've taken you there.
• 12:59
  SPEAKER_01: I took you there when you were a high school student.
• 13:01
  SPEAKER_01: That's right.
• 13:01
  SPEAKER_01: And then you've actually joined me when I was teaching another class.
• 13:06
  SPEAKER_01: You were you you joined us, right?
• 13:07
  SPEAKER_00: That's right.
• 13:08
  SPEAKER_00: Yeah.
• 13:08
  SPEAKER_00: I went up there.
• 13:09
  SPEAKER_00: I think I was I had graduated college by that point, but I was a chaperone along on your geology trip, which was very fun.
• 13:15
  SPEAKER_01: I really need to do better with my chaperones if if you Yeah, yeah, no, you you need to be more selective for sure.
• 13:20
  SPEAKER_01: Um, uh is that you getting us back on track?
• 13:23
  SPEAKER_00: Yeah, yeah, trying to get back on track here.
• 13:26
  SPEAKER_00: Okay, cross bedding is so cool.
• 13:28
  SPEAKER_00: So cross bedding is it's kind of self-described here in the name.
• 13:32
  SPEAKER_00: It's beds that cross each other, cross-cut each other.
• 13:35
  SPEAKER_00: And you can imagine it looks like you'll have a layer, a horizontal layer of a bedding plane.
• 13:39
  SPEAKER_00: So this is a depositional plane uh in the rock, and a big scoop will be taken out of one side of it.
• 13:45
  SPEAKER_00: And that scoop will have other layers that cross-cut the older layers.
• 13:50
  SPEAKER_00: And then these things are stacked up on top of each other over time.
• 13:53
  SPEAKER_00: And the way that this works is imagine a dune that's sand is blowing up one side and down the other side.
• 14:00
  SPEAKER_01: All right, Jesse, I'm gonna interrupt you here.
• 14:02
  SPEAKER_01: The stose side is what that's called in geology, which is the side where the wind is coming from, because you used a dune analogy.
• 14:10
  SPEAKER_01: And so what happens is these imagine grains of sand getting blown by the wind and they they're lifted a little bit and then they land and they get lifted again.
• 14:17
  SPEAKER_01: That's called saltation.
• 14:18
  SPEAKER_01: So they saltate their way up to the top of the dune, where then you get at that ridge of the dune, you get a this accumulated sand until it gets too steep and it can't support that little buildup ridge anymore, or or just the current of the wind pushes it over, and it now pushes the sand down the lee side of the dune, which is the side opposite from the wind where the wind is coming from.
• 14:42
  SPEAKER_01: So we have stos and lee side of a dune.
• 14:45
  SPEAKER_01: And so you get this deposition that follows the lee side, the angle of the slope, you get these depositional layers on that side, and that's called crossbedding.
• 14:55
  SPEAKER_01: Okay, and then what'll happen then is the wind will shift direction, and you'll get then new layers that are deposited on the lee side at a slightly different angle to the beds below it.
• 15:06
  SPEAKER_01: So that's why we get what we call crossbedding.
• 15:09
  SPEAKER_00: And these dunes are constantly moving in one direction from the other.
• 15:12
  SPEAKER_00: So as you're blowing sand up one side and down the other, that dune is actually migrating forward with the wind.
• 15:18
  SPEAKER_00: And over time, these things pile up on top of each other and generate crossbedding.
• 15:22
  SPEAKER_00: So anything where you have flowing wind or water that is moving things like dunes, you'll get crossbedding.
• 15:29
  SPEAKER_00: And so this can happen in a river system where you're doing exactly the same process, except now it's water moving the sediment instead of wind moving the sediment.
• 15:38
  SPEAKER_00: And so crossbedding is this beautiful representation.
• 15:43
  SPEAKER_00: In a rock, we can see an ancient surface process being preserved in there.
• 15:47
  SPEAKER_00: And crossbetting is just a great example of this.
• 15:50
  SPEAKER_01: That's right.
• 15:50
  SPEAKER_01: And crossbedding is so important to geologists to determine depositional environment.
• 15:57
  SPEAKER_01: Was this a tidal setting?
• 15:59
  SPEAKER_01: Was this a dune setting?
• 16:00
  SPEAKER_01: What was the paleocurrent coming from, or the direction that the ancient wind came from, or the ancient river came from?
• 16:08
  SPEAKER_01: So they're really, really important to help us reconstruct the geologic history of that location.
• 16:14
  SPEAKER_00: So, Chris, we're focusing on the Corbin sandstone here, but you know, this isn't formed in isolation.
• 16:19
  SPEAKER_00: There's rocks above and below in this process.
• 16:22
  SPEAKER_00: So we'll get to why we're focusing on the Corbin sandstone in a minute, but what's above and below it?
• 16:27
  SPEAKER_01: Massive accumulations of sediment to be blunt.
• 16:30
  SPEAKER_01: The layer right below it is called the Nancy member, and it's a weakly lithified siltstone and shale or clay rich member.
• 16:41
  SPEAKER_01: Um, it's pretty cool looking, actually.
• 16:43
  SPEAKER_01: I I have a big slab of it, it's really dark green color, but I don't keep it outside because it's so soft and crumbly that it won't last long.
• 16:52
  SPEAKER_01: So I've learned that stuff like that I got to keep more protected.
• 16:55
  SPEAKER_01: Um, and so seeing as this is below the Corbin member, that means geologically it's older.
• 17:02
  SPEAKER_01: So this layer was deposited between 359 to 331 million years ago.
• 17:08
  SPEAKER_01: It's kind of cool too.
• 17:09
  SPEAKER_01: Uh not only is it's color beautiful, but it also has very interesting fossils.
• 17:15
  SPEAKER_01: They're called zoophykos.
• 17:17
  SPEAKER_01: They indicate the the fossils and the type of sediment is that this was a much lower energy and deeper marine setting than what the Corbin sandstone is.
• 17:27
  SPEAKER_01: So, and then above the Corbin sandstone again, we have just massive accumulations of sediment.
• 17:33
  SPEAKER_01: In this area, though, they've been eroded away, they've been removed further away to another basin and deposited yet again.
• 17:41
  SPEAKER_01: So, again, massive amounts of sediment above and below it.
• 17:45
  SPEAKER_00: And you touched on the really the key point and why we are focusing on the Corbin sandstone here is that the sediment below it is really weak.
• 17:55
  SPEAKER_00: This Nancy member is really weak, you can't even leave it outside your house in Michigan because it'll break apart.
• 17:59
  SPEAKER_00: That sandstone you could leave outside for a long, long time in Michigan and it wouldn't break apart.
• 18:04
  SPEAKER_00: So the resistant Corbin sandstone means that when this area is uplifted above sea level now, that Corbin sandstone is resistant and will be able to form a gorge through it, which is now the Red River Gorge.
• 18:18
  SPEAKER_00: And the stuff under it could not preserve a gorge of this magnitude, whereas this resistant sandstone can actually have a river cut right through it and not be eroded along the sides and make a big wide valley.
• 18:30
  SPEAKER_00: So that brings us, Chris, to the regional uplift, which is kind of part four in the geologic story here.
• 18:37
  SPEAKER_00: What got from this sandstone depositing shallow sea environment to what we see today?
• 18:43
  SPEAKER_01: Just speaking in really general terms, we had this broad kind of regional uplift.
• 18:49
  SPEAKER_01: And we're not talking about here mashing together this the kind of massive, violent, tectonic collision going on here.
• 18:57
  SPEAKER_01: This is more of this, it's kind of Jesse.
• 19:00
  SPEAKER_01: Like, if I said, hey, take a deep breath and your chest kind of heaves, that's like a regional, broad uplift that we're talking about here.
• 19:09
  SPEAKER_01: It formed what's now known as the Cumberland Plateau, and it goes really from Alabama to western New York.
• 19:16
  SPEAKER_01: It was gentle enough that it kept everything relatively flat yet, but it lifted this area up to 600 or so meters above sea level.
• 19:27
  SPEAKER_01: So, you know, on the order of maybe 2,000 feet-ish above sea level.
• 19:30
  SPEAKER_00: And so now these rocks are exposed above sea level.
• 19:33
  SPEAKER_00: The ones above the Corbin Sandstone have been eroded away, which there weren't it drained the sea.
• 19:38
  SPEAKER_00: It drained the sea, exactly.
• 19:40
  SPEAKER_00: And then started this erosion process that we kind of see the representation of today.
• 19:46
  SPEAKER_00: And so the modern, then bring us forward to the modern Red River and all its tributaries.
• 19:51
  SPEAKER_00: Where does this come from?
• 19:52
  SPEAKER_00: What's going on currently to form the gorge?
• 19:56
  SPEAKER_01: That's the perfect question.
• 19:57
  SPEAKER_01: This is like the last stage in the formation of how do we get from where we started with the formation of the Appalachians to the Red River Gorge looking like it does today?
• 20:08
  SPEAKER_01: This last and final stage, now it's all about erosion.
• 20:12
  SPEAKER_01: It's erosion by the Red River, and it by the way, it the Red River in that whole region gets its name because the rocks, the Corbin sandstone, they're iron-rich, and so they've oxidized into shades of orange and red, they're beautiful.
• 20:28
  SPEAKER_01: So hence the name Red River Gorge because of the rocks that they're cutting through.
• 20:32
  SPEAKER_01: But the Corbin sandstone has a lot of these vertical fractures in it, and so fractures they form a path of least resistance for water.
• 20:44
  SPEAKER_01: And so water, then running water, moving water streams, exploits these.
• 20:49
  SPEAKER_01: And that's the beginning, then, these cracks and fractures, the beginning of a river canyon developing or a gorge developing.
• 20:57
  SPEAKER_01: And that's really where we're at, is just the exploitation of the fractured Corbin sandstone.
• 21:03
  SPEAKER_00: Yeah, this fracture process, you can kind of think of it in really simplistic terms of I don't know what the the a piston beneath some sort of a cake or something like that.
• 21:12
  SPEAKER_00: You know, if you put a cake down on a on a rounded table, it's going to kind of crack at the top because it's kind of bending and folding around it.
• 21:19
  SPEAKER_00: That's more or less what's going on here is you're creating these vertical cracks because the rock is being split by this uplift part, and then the river is exploiting that system and that process.
• 21:30
  SPEAKER_00: And this really leads to the natural beauty of this area, right, Chris?
• 21:36
  SPEAKER_00: And we have two main features that we're going to talk about here: arches and bridges.
• 21:41
  SPEAKER_00: Those are kind of in the same category here, and then the coloration, the lysgang banding.
• 21:46
  SPEAKER_01: That's right.
• 21:47
  SPEAKER_01: So we talked about this.
• 21:48
  SPEAKER_01: I'm gonna go ahead and cover as best I can the arches and bridges and how they form and distinguish between them.
• 21:55
  SPEAKER_01: Uh I want you to to cover this lice gang banding or It's I don't know, Jesse.
• 22:01
  SPEAKER_01: Is it it's Lee's gang or Li's gang?
• 22:03
  SPEAKER_01: Uh yeah.
• 22:04
  SPEAKER_01: No.
• 22:04
  SPEAKER_00: I th I I think it's Lee's gang, but um I'm not really sure.
• 22:07
  SPEAKER_00: Okay.
• 22:07
  SPEAKER_00: Okay.
• 22:08
  SPEAKER_01: I'm gonna have I'm gonna have you talk about the Lee's gang banding because it's very doctory and you're the doctor in the house.
• 22:15
  unknown: Right.
• 22:16
  SPEAKER_01: Very doctory.
• 22:17
  SPEAKER_01: I I figure it's appropriate for the professor in the house to to there's a lot of doctory stuff too with regard to these arches and bridges, I think.
• 22:27
  SPEAKER_01: I know you know it's crazy.
• 22:28
  SPEAKER_01: So jump in if you want.
• 22:29
  SPEAKER_01: Go ahead, there's a lot of things.
• 22:30
  SPEAKER_00: There's doctory stuff everywhere here.
• 22:32
  SPEAKER_00: But okay, so there's two names here when you're looking, and I've again never been here.
• 22:38
  SPEAKER_00: So when I was looking online, I'm like, okay, there's things called bridges, there's things called arches.
• 22:43
  SPEAKER_00: What the heck is the difference here?
• 22:45
  SPEAKER_00: Can you guide us?
• 22:46
  SPEAKER_00: Give us a guide through the differences and how they're formed.
• 22:50
  SPEAKER_01: Okay.
• 22:50
  SPEAKER_01: I'll do my best.
• 22:51
  SPEAKER_01: It's very, very confusing.
• 22:54
  SPEAKER_01: And so here's the bottom line: a natural bridge is formed by running water erosion.
• 23:04
  SPEAKER_01: An arch is formed by weathering minus the running water.
• 23:10
  SPEAKER_01: That's the technical distinction between them.
• 23:14
  SPEAKER_01: But the confusion happens because these names are old, right?
• 23:19
  SPEAKER_01: This so they named all these bridges and arches that they have in the Red River Gorge area.
• 23:24
  SPEAKER_01: They were named by people that had no real understanding of geology necessarily, they're just named, right?
• 23:30
  SPEAKER_01: And so they'll name them bridges when they're arches, and they have arches that they named bridges, and they just kind of interchange the term bridges and arches all the time.
• 23:40
  SPEAKER_01: So it is splitting of hairs, actually, and it's a little annoying for me that we do this.
• 23:45
  SPEAKER_01: I don't know.
• 23:46
  SPEAKER_01: This is where you somebody gets doctory.
• 23:48
  SPEAKER_00: We've talked before about how you're a lumper.
• 23:50
  SPEAKER_00: Actually, you had a job as a watermelon lumper, and you so you like lumping things in general.
• 23:56
  SPEAKER_01: I like simplification, I like geology.
• 23:59
  SPEAKER_01: Here's my thing, Jesse, is geology needs to be explained in ways that can be understood by the many, not the few.
• 24:09
  SPEAKER_01: And lumping, okay, helps that along, I think.
• 24:12
  SPEAKER_01: You know, like we we don't always need to go down the rabbit hole of well, I okay.
• 24:19
  SPEAKER_00: Yes, I beg to differ.
• 24:20
  SPEAKER_00: I like to go down the rabbit hole, but yes, you're right.
• 24:22
  SPEAKER_00: Nobody, we don't need to go down this rabbit hole too far.
• 24:24
  SPEAKER_00: But either way, whether it's an archer bridge, what's the take-home summary lumper version of how they're formed?
• 24:31
  SPEAKER_01: Yeah, I think I got this.
• 24:32
  SPEAKER_01: I want to use an analogy.
• 24:34
  SPEAKER_01: So we talked earlier about the fractures in the Corbin sandstone.
• 24:38
  SPEAKER_01: Well, these fractures lead to the formation of ridges.
• 24:43
  SPEAKER_01: So let's talk about this.
• 24:44
  SPEAKER_01: I want everybody to envision a book.
• 24:48
  SPEAKER_01: Or so if we take a book and we put the binding edge down on the tabletop, so the pages are sticking up.
• 24:55
  SPEAKER_01: Okay, in other words, the front cover of the book is facing to the side and the back cover of the book is facing to the other side.
• 25:02
  SPEAKER_01: So the pages themselves represent the fractures in the Corbin sandstone.
• 25:07
  SPEAKER_00: Okay, I'm with you.
• 25:08
  SPEAKER_01: Does that make sense?
• 25:09
  SPEAKER_01: So they they extend down through the Corbin, right?
• 25:13
  SPEAKER_01: But the fractures are roughly parallel to each other.
• 25:16
  SPEAKER_01: Now, if you throw in weathering and erosion and rivers, all of it, let's throw it all in there, some of those pages are gonna fall down to the tabletop.
• 25:26
  SPEAKER_01: Okay.
• 25:26
  SPEAKER_01: But the middle of the book will be the last to go because it's protected by these other fractures that are on the sides of it.
• 25:35
  SPEAKER_01: Okay.
• 25:36
  SPEAKER_01: Does that make sense?
• 25:36
  SPEAKER_01: Yeah, it is.
• 25:38
  SPEAKER_00: This is a good analogy.
• 25:39
  SPEAKER_00: I like this one.
• 25:39
  SPEAKER_00: Yeah, absolutely.
• 25:41
  SPEAKER_00: So So you're kind of peeling off the layers of this book, and what you're left with.
• 25:46
  SPEAKER_01: That's right.
• 25:47
  SPEAKER_01: I'm peeling the first pages of the book off, and I'm peeling the last pages of the book off, but I'm leaving the middle standing straight up.
• 25:54
  SPEAKER_01: Okay.
• 25:56
  SPEAKER_01: So in the end, what you have then is a narrow ridge.
• 26:01
  SPEAKER_01: And what happens then is well, you either get a bridge or an arch, okay, if we're gonna distinguish between them.
• 26:09
  SPEAKER_01: And so if you have water that flows off each side of the ridge, this narrow ridge that's left, this kind of spine, or it's think of it like a fin, okay.
• 26:20
  SPEAKER_01: Then it will create the beginning, it'll scour out the middle of that ridge.
• 26:28
  SPEAKER_01: What happens then is it once it's breached through, you have the beginning of you know, a little pinhole, a little arch, right?
• 26:36
  SPEAKER_01: Now, there this is kind of cool too.
• 26:38
  SPEAKER_01: Once this happens, it becomes a self-fulfilling prophecy, kind of, because recent research suggests how now I have the edges of the pillars of the arch, and it gets compressed, which makes the sandstone actually more durable.
• 26:57
  SPEAKER_01: It's more resistant to weathering and any erosion because of the compression that's taken place.
• 27:02
  SPEAKER_00: Yeah, and the way to think about this this is a really cool research article, I think you found by Brethens et al.
• 27:07
  SPEAKER_00: Uh, where they did some experiments about this to try and model how this happened, both in the lab and numerically simulated.
• 27:12
  SPEAKER_00: But you're right, this is a feedback loop of if you you can think of it like standing on one leg versus standing on two legs.
• 27:18
  SPEAKER_00: If you're standing on two legs, you're distributing your weight more.
• 27:21
  SPEAKER_00: And if you stand on one leg, you're distributing your weight less and it's more focused on one leg.
• 27:27
  SPEAKER_00: And so the pressure, the vertical pressure on that one leg is higher.
• 27:31
  SPEAKER_00: Which means in a sandstone, you're putting vertical pressure on these sand grains and you're kind of annealing them together, making that stronger.
• 27:39
  SPEAKER_00: And so this is the process that's going on to make these arches is there's this positive feedback loop where if you erode more around the edges, you're putting more of that weight, that high weight is being focused down vertically, which strengthens the rock, which makes it harder to erode.
• 27:54
  SPEAKER_00: And that was a really cool, really cool process.
• 27:57
  SPEAKER_01: It is.
• 27:57
  SPEAKER_01: And and then what happens eventually, right, is the arch itself will be the next thing to collapse, leaving the pillars that used to be connected by the arch uh standing alone.
• 28:10
  SPEAKER_01: So we get to see all of this in the Red River Gorge.
• 28:14
  SPEAKER_01: I mean, the arches, there are over a hundred natural bridges and arches in this area, and it's it makes it a destination.
• 28:22
  SPEAKER_01: They're beautiful, they're curious, they're awesome, and that's how they form.
• 28:28
  SPEAKER_01: I don't know.
• 28:28
  SPEAKER_01: Did did we nail that or not?
• 28:30
  SPEAKER_01: I think so.
• 28:30
  SPEAKER_00: Yeah, that's uh really interesting and a really great place to see arches.
• 28:34
  SPEAKER_00: You know, Arches National Park in Utah is another place where there's a lot of arches around, and it's a sort of a different erosional process, but it is a little because Arches National Park, it created these ridges or fins in a totally different way.
• 28:51
  SPEAKER_01: In arches, it did this by a salt dome, by burial of rock salt, and when it gets buried to a certain depth, it becomes actually fluidized, and so this fluid gets squeezed laterally until it can uh find a zone of weakness leading closer to the surface, and it forms what we call in geology a diaper or these like upside-down teardrops that domed up the sandstone.
• 29:15
  SPEAKER_01: Well, sandstone's brittle, and that doming caused it to crack into these ridges.
• 29:20
  SPEAKER_01: So the fin forming process of Arches National Park is different from what was going on in the Corbin sandstone.
• 29:27
  SPEAKER_00: So is it time to move on to Lee's gang banding?
• 29:31
  SPEAKER_01: Yeah, can we get doctory here?
• 29:32
  SPEAKER_01: Let's do this.
• 29:33
  SPEAKER_01: Let's let's get professory.
• 29:35
  SPEAKER_00: We're gonna try to stay out of the weeds too much.
• 29:38
  SPEAKER_01: All right, Jesse.
• 29:39
  SPEAKER_01: This Lee's gang banding is so cool.
• 29:43
  SPEAKER_01: And the first time I was there, it you know, first times you remember, it's these what it is, these swirling bands of dark red, dark brown, bright orange swirls in the rock.
• 29:58
  SPEAKER_01: And to me, they looked like uh soft sediment deformation.
• 30:03
  SPEAKER_01: The kind of thing that happens with a tsunami, you know, like those really prominent swirls, but it has nothing to do with that at all.
• 30:11
  SPEAKER_01: It's not soft sediment deformation, it's something entirely different.
• 30:17
  SPEAKER_00: Take it away, Dr.
• 30:18
  SPEAKER_00: Rhyme.
• 30:19
  SPEAKER_00: So the word we're saying here is lease gang, which is L-I-E-S-E-G-A-N-G, Lease Gang, and it's not a sediment depositional feature because these bands, these coloration bands, cross-cut the depositional layers.
• 30:36
  SPEAKER_00: So we know what happened after the sediment formed.
• 30:38
  SPEAKER_00: Now, there's a whole field of research on what these bands actually represent.
• 30:43
  SPEAKER_00: And there's a big discussion about the processes behind these bands and how they're actually formed.
• 30:49
  SPEAKER_00: They were discovered, this type of concentric banding was actually discovered in gel experiments.
• 30:54
  SPEAKER_00: So take a gel in a cylindrical test tube, drop some other substance in it, some dye in it, and you would expect if you think of it in water, you if you drop a bit of food coloring into water, it'll just kind of diffuse through it and it'll change the color of the water.
• 31:09
  SPEAKER_00: With a gel, this didn't happen.
• 31:11
  SPEAKER_00: You drop some dye in there, and it formed these concentric rings that were spaced equally apart.
• 31:17
  SPEAKER_00: And depending on what kind of stuff you dropped into the gel, it would form different spacings of the bands.
• 31:22
  SPEAKER_00: And you can actually get some really interesting corkscrew patterns in this.
• 31:25
  SPEAKER_00: So least gang banding is a chemical phenomenon that is observed in various ways that is not restricted to just rocks.
• 31:33
  SPEAKER_00: This is one part of the least gang phenomenon is in rocks, as we see in Red River Gorge.
• 31:40
  SPEAKER_00: But it basically works.
• 31:41
  SPEAKER_00: There's many nuanced in the weeds debates about how this process forms, but it's basically fluids moving through the rock and diffusion happening.
• 31:50
  SPEAKER_00: So you can think of this as the chemical experiment you might have done in chemistry class where you supersaturate some liquid.
• 31:59
  SPEAKER_00: So you kind of like, you know, heat up some liquid, dump a ton of salt in it or a ton of sugar, and cool that thing down and then drop a little piece of sugar in it and it nucleates.
• 32:08
  SPEAKER_00: All the sugar kind of saturates out.
• 32:10
  SPEAKER_00: What you're doing there is forming a super saturated liquid.
• 32:12
  SPEAKER_00: If there is too much sugar in it, then there should be, like it's oversaturated in sugar in the solution, and it wants to precipitate out, but all it needs is that seed.
• 32:21
  SPEAKER_00: You have to have that little seed to get it to precipitate out.
• 32:24
  SPEAKER_00: You can kind of think of it this way: that these bands are representing zones that got supersaturated, and then they nucleated, that seed was there, and boom, they precipitated out.
• 32:34
  SPEAKER_00: And what it does is it soaks up all the chemicals from the areas around it into that band very rapidly.
• 32:42
  SPEAKER_01: And that supersaturated material that we're referring to is rust.
• 32:47
  SPEAKER_01: It's iron oxide, right?
• 32:49
  SPEAKER_00: That's right.
• 32:50
  SPEAKER_01: And it's super tough, very, very resistant material.
• 32:57
  SPEAKER_01: And so these Lees gang bands often stick out, they'll protrude from the Corbin sandstone.
• 33:03
  SPEAKER_00: That's important to note, Chris, that we can put these in order of events then, right?
• 33:07
  SPEAKER_00: The Leesgang banding formed before the erosion happened, right?
• 33:12
  SPEAKER_00: So the erosion is preferentially weathering and eroding different bands in the Leesgang banding because of the chemical reactivity of those things.
• 33:20
  SPEAKER_00: The darker bands and the lighter bands have different preferences, different strengths to them.
• 33:26
  SPEAKER_01: And also to point out, too, is the Leesgang banding is one of the reasons why the Corbin sandstone in the Red River Gorge area is a climbing mecca.
• 33:36
  SPEAKER_01: It makes for awesome hand holds, you know, it's because they stick out and you can just totally.
• 33:41
  SPEAKER_00: Yeah, that's great.
• 33:43
  SPEAKER_00: So that's uh a brief intro.
• 33:45
  SPEAKER_00: Lee's gang banding is kind of everywhere in nature, in chemistry.
• 33:49
  SPEAKER_00: It's very interesting, very probably important, not well understood.
• 33:52
  SPEAKER_00: Let's get to some hiking recommendations, Chris.
• 33:54
  SPEAKER_01: Hold on a second, though.
• 33:55
  SPEAKER_01: Can you just do a 15-second?
• 33:58
  SPEAKER_01: I mean literally like 15-second summary of Lee's gang.
• 34:02
  SPEAKER_01: What's the takeaway with it?
• 34:03
  SPEAKER_01: Okay, because you you got rambly there, and I mean that in the most affectionate way.
• 34:09
  SPEAKER_00: Right, right, of course.
• 34:11
  SPEAKER_00: The okay, so 15-second takeaway.
• 34:13
  SPEAKER_00: Lee's gang banding is something that happened after the sediment was formed by fluids flowing through the rock, depositing different minerals in different locations to create these beautiful concentric zoned rings that then weathering overprints or weathering attacks differently to form the physical structures, the relief that you see sometimes.
• 34:33
  SPEAKER_00: So, Chris, let's finish up here really quick with some hiking recommendations.
• 34:38
  SPEAKER_00: Where are some good places to go to see some of the stuff that we're talking about?
• 34:43
  SPEAKER_01: Okay.
• 34:43
  SPEAKER_01: Um, well, anywhere.
• 34:46
  SPEAKER_01: Uh honestly, like anywhere.
• 34:50
  SPEAKER_01: It's it's such a cool place.
• 34:51
  SPEAKER_01: Um, I do want to throw a shout out, and this is not we're not advertising it all here, but Miguel's pizza is amazing.
• 34:58
  SPEAKER_01: Okay, it's so cool.
• 35:00
  SPEAKER_01: Um, all right, I'm gonna do this in no particular order, but I have three main recommendations here that vary in length, and and you have all kinds of options too, Jesse, with all of these.
• 35:11
  SPEAKER_01: Actually, there's so many different offshoots that you can take.
• 35:14
  SPEAKER_01: So you can you can take what I'm giving you here and make it much longer.
• 35:18
  SPEAKER_01: You can actually take what I'm given and make it much shorter.
• 35:21
  SPEAKER_01: I'm gonna begin the natural bridge.
• 35:23
  SPEAKER_01: It's an icon in the park, it obviously takes you to this beautiful natural bridge.
• 35:28
  SPEAKER_01: I don't know much else to say about it.
• 35:30
  SPEAKER_01: It's awesome.
• 35:31
  SPEAKER_01: You get great Lee's gang banding examples in here, great crossbetting.
• 35:36
  SPEAKER_01: You can actually see in some of the Corbin sandstone, you can see some fossilized petrified wood.
• 35:42
  SPEAKER_01: These were from trees that got that were being carried by the rivers that resulted in the deposition of the Corbin.
• 35:48
  SPEAKER_01: So it's very cool and it's it's very example-rich of things that typify the beauty of this place.
• 35:55
  SPEAKER_01: The next one is Auxer Ridge Trail.
• 35:58
  SPEAKER_01: And this is again, you see crossbedding like crazy on this trail.
• 36:02
  SPEAKER_01: Again, it indicates this kind of tidal deltaic sediment depositional environment that was going on.
• 36:09
  SPEAKER_01: And it also in this area, too, it indicates that this was deposited in an estuarian environment.
• 36:16
  SPEAKER_01: So an estuary is this kind of submergent coastline or or drowned river mouth.
• 36:23
  SPEAKER_01: And you you live near estuaries, right?
• 36:26
  SPEAKER_00: Yeah, near kind of near, don't you?
• 36:27
  SPEAKER_00: Like we're close, we're close enough to the Chesapeake Bay to in the influence, yeah, for sure.
• 36:32
  SPEAKER_01: That's right.
• 36:32
  SPEAKER_01: That's right.
• 36:33
  SPEAKER_01: Um, and there are different examples of what you can do here.
• 36:36
  SPEAKER_01: We took the long one, you know, it's like a I don't know, it ended up maybe being a 12-mile day for us.
• 36:41
  SPEAKER_01: It's flat and then it's down and then it's up, and it's but it's awesome all the way.
• 36:45
  SPEAKER_01: It uh takes you out to like double arch, which is super cool because you they're stacked up on top of each other.
• 36:52
  SPEAKER_01: There's a place, it's a famous landmark called Courthouse Rock, which is this huge monolith that has flat square sides on each part of this thing.
• 37:02
  SPEAKER_01: It's it just sticks up like a sore thumb.
• 37:04
  SPEAKER_01: It's pretty amazing.
• 37:06
  SPEAKER_01: So that's Augsir Ridge Trail.
• 37:08
  SPEAKER_01: It's a cool hike.
• 37:09
  SPEAKER_01: My favorite though is going to Cloud Splitter via Indian staircase.
• 37:15
  SPEAKER_01: Now, this it's it's not really a a big deal, but there is some exposure on this, and and people every meaning if you get a little bit nervous because you're uh pretty high up and there's a cliff right next to the street.
• 37:27
  SPEAKER_01: Yeah, you can get hurt for sure.
• 37:28
  SPEAKER_01: Yeah, and every month there's always a search and rescue that involves either going to the top of Cloud Splitter or up Indian staircase, uh, just because people uh you know take it for granted, I think.
• 37:41
  SPEAKER_01: So there is exposure there, but it's my favorite.
• 37:44
  SPEAKER_01: When you end up on top of Cloud Splitter, and there is, by the way, a rope that is fixed to use to get you up to the top of it, and it's highly advisable to use that rope going up and down.
• 37:56
  SPEAKER_01: When you get out onto that point and you can see the confluence of two tributaries merging into the Red River, it's a destination on a great day.
• 38:06
  SPEAKER_01: Yeah, awesome.
• 38:07
  SPEAKER_01: Bring a beer, sit there, relax, contemplate life.
• 38:12
  SPEAKER_00: It's awesome.
• 38:13
  SPEAKER_00: Awesome.
• 38:14
  SPEAKER_00: Well, that's uh sounds like some uh great recommendations there, Chris.
• 38:17
  SPEAKER_00: And uh I'll I'll have to go check it out.
• 38:19
  SPEAKER_00: I have never been.
• 38:20
  SPEAKER_00: Uh gets me excited to go check these things out.
• 38:23
  SPEAKER_00: It'll be awesome.
• 38:24
  SPEAKER_00: This is within driving distance with us, so that's we'll be able to make it.
• 38:27
  SPEAKER_01: And winter is a great time.
• 38:29
  SPEAKER_00: Winter is a great time.
• 38:30
  SPEAKER_00: Yeah, sweet.
• 38:31
  SPEAKER_00: Well, hey man, I think that's a wrap here.
• 38:34
  SPEAKER_00: You bet.
• 38:34
  SPEAKER_00: I think so.
• 38:35
  SPEAKER_00: All right.
• 38:36
  SPEAKER_00: Well, follow us on all the social medias.
• 38:37
  SPEAKER_00: We're at Planet Geocast.
• 38:39
  SPEAKER_00: Send us an email.
• 38:40
  SPEAKER_00: We love that stuff.
• 38:40
  SPEAKER_00: We love hearing from everybody about what they liked, what they didn't like, what their questions are based on episodes, and give us a like, subscribe, review, rating.
• 38:48
  SPEAKER_00: Those really help the algorithm and really help us teach geoscience to everybody.
• 38:54
  SPEAKER_01: That's right.
• 38:54
  SPEAKER_01: And please just share it with somebody that you think that you know loves our planet, loves the beauty of it, and how it all works.
• 39:00
  SPEAKER_01: Share it with them.
• 39:03
  SPEAKER_00: That's a wrap.
• 39:04
  SPEAKER_00: See you next week.
• 39:05
  SPEAKER_00: Cheers.