What is This Massive Crater Like Hole in the Utah Desert

In the Four Corners region of the American Southwest, there's this unique crater-like feature that caught my eye a while back while I was mapping out a route for an earlier adventure on the channel. It has stayed with me ever since. Knowing I'd be driving through the area again soon, I committed to finding my way there. I wanted to stand on the rim of this massive cliff and to explore this impressive surrounding landscape, specifically to answer a few questions. How did this huge crater-shaped depression get here, and could I navigate through this jagged yet stunning uplift just below it to gain access to it? Instead of off-roading straight to the top like it appeared I could, I started low and to the east, moving on foot to get a close, personal, and detailed look at it all. So we have two unique challenges today, one being geographical and the other navigation only kind of compound. I chose a route without a trail, so we're just going to be route finding through the backcountry here, and we're going to have to get through that massive linear escarpment, the monocline, with all of those really cool fins, these beautiful colors. I'm really excited to actually get in there and check those out. But that also presents a geographic challenge because a lot of those fins drop into cliffs, and there's right ways and wrong ways to go, at least looking on Google Earth and the maps. And from the bottom it's going to be impossible to tell if you're choosing a good route because you're so far below you cannot see if the little drainage that you're goes through or just turns into a box canyon. So between my maps, my drone, trial and error, we're going to do our best to summit this ridge, get up on top. If you've spent a good amount of time exploring the southwest, then you know what this huge hedge of shrubs behind me is. It's tamarisk. It's an invasive shrub that came from Asia and has just completely dominated the river corridors and riparian areas of the southwest over the last decades. We've done a lot to try and eradicate it. I mean, scientists have engineered genetically modified beetles to specifically predate on it. I've been involved in a number of restoration projects just going in and, through brute force, digging it out and planting it native willows. But sometimes it kind of feels like it's all in vain because you'll go back and visit these places and it's just come back twice as thick. And it's creating another barrier for me. We got to get through this. I thought I had, you know, like two barriers. I thought it was just going to be navigation and that massive monocline, but we have this great wall of tamarisk to get through and it can just be nasty. Thankfully, it's not full of thorns like some of the other invasive species in these corridors like Russian olive, but it's still really nasty to get through. Okay, let's see if we can find a way through this. Easier for you, huh, cowboy? Okay, we are through. As I moved closer to the uplift, I needed to find a way through it. One useful technique in terrain like this is to study the larger the debris fan at the mouth, the larger the drainage above it. And the larger the drainage, the more erosion it's likely experienced, which usually means a wider, more navigable route. So, I chose the canyon near the San Juan River with the biggest deposit. Even though it appeared to end in impassable cliffs, there was still a possibility. If I followed the canyon floor far enough, I could break north onto a bench of harder stone, side-hilling out of the drainage, gaining the ridge, and eventually climbing onto the mesa towards our final destination. It wasn't guaranteed, but it's our best bet. I'm liking our odds with that approach. Instead of trying to stay in a drainage all the way up and getting cliffed out in a box canyon, find a ridge, gain the ridge, and use the more eroded, sloped ridgeline to access the top of that plateau. The reality is, you just don't really know. It can look good from one perspective, but the drainage can be incredibly vegetated and hard to get through with boulder fields or could have been a cliff I didn't really see and not able to get past. But we're gonna go find out, and it'll be good to visit the San Juan River before we climb up and out for both of us. Good little swim for Cowboy and a camel up for the both of us. And there she is, the mighty San Juan River. One of the life arteries in the Four Corners area. What a beaut. Cowboy's excited. The San Juan River flows west to meet the Colorado River in Lake Powell. Historically, it was one of the Colorado River's most sediment-rich tributaries before getting dammed up and now often flowing clear and green. Upstream near Pagosa Springs, it's a cold mountain river. By the time it reaches the Utah desert, it's warmer and more silt-heavy after rain runoff. For the ancestral Puebloan and later the Navajo Inuit peoples, this corridor was a lifeline and their archaeological sites dot the riverbanks. Yeah? You gross wet dog? You gross and wet? Well, that was a lovely and productive little visit to the San Juan River, so we're going to backtrack a little bit. We're going to go to that larger canyon entrance into the monocline. We'll gain access there, and that'll be cool because starting by staying low deep into that canyon, we're going to get a nice cross-section of all of the layers that we're going to have to ascend up to gain that higher plateau. You know, it's funny. Every once in a while you'll feel like you're exploring something, maybe seeing something that no one else has seen, and I had my eyes set to large-scale observation looking at these huge features, and I came walking across right here, and then you can't avoid just running in to evidence of the ancients out here everywhere, and we're right at the base of the monocline. It's a bit of a reminder that I'm traveling through an utterly explored and discovered, lived-in landscape no matter where I go. Another one, too. Look at this. Painted. I keep coming across these mounds. There's one here, and it's hard to see on camera, but they're kind of littered throughout the landscape, and then there's another one right over here. You can see how there's a higher density of rocks, and if you actually get close, it is full of potsherds. Okay, we've made it to the entrance canyon that we have chosen, and right alongside there's this big bluff. Curiosity got the better of me, and we have this massive carved-out circular dwelling area. Clearly been worked by the hands of man at some point. We have this outer barrier of rocks kind of creating this nice level surface, and then, of course, as we get close, we're going to see potsherds kind of everywhere strewn about, various artwork styles hiding in the rocks. Pretty damn good view, too. Look out over the river. Some raptors going down the river, and I mean this is huge. It's at least 100 feet across. All right, so we've made our way down off the top of that bluff from that hilltop site. We have entered this drainage. This will be our access. Coming up, this is the gates, our entrance. Hopefully, we can gain the ridge going through this drainage. This will be exciting. Clearly, this place floods frequently, but this is the beginning. Let the climb begin. Something that's easy to notice right off the bat, now that we're in the bed of this wash, is that clearly we're surrounded by this incredibly red sedimentary layer. Looks like a mudstone or a siltstone, but if you look at the floor, what we're walking on, you see a mix of different types of rocks. It's not just that red. I'm seeing this lighter limestone being mixed in alongside all of this red siltstone. That's a bit of a preview for what we're going to have to hike through as we ascend this drainage and gain the ridge. We have some native reeds and a wetlands plant, which is really cool. I was partially worried because I thought it might get dense and hard to pass, but we'll just kind of navigate this and see how this goes. We have water in here too. A flowing spring. This looks like a perennial spring almost. We've got cattails and reeds, and it looks like we're finally making our way out of this thicket. This spring is just wonderful. We've officially... Oh, look at that. We're in the limestone now. Look at that transition. Here we go. That's good news. So the silt comes out of the limestone and would appear a little further up. The water is clear. It's gorgeous. I think we need to go up soon. Pausing to scout the rest of this canyon, you can follow the lighter colored limestones and red and purple siltstones that were deposited from a shallow inland sea during the Paleozoic all the way to the top where it ends in an impassable cliff band that I will need to avoid. Okay, so after doing some scanning with the drone, it's time to depart up the side of this canyon to avoid getting cliffed out in a box canyon up ahead. So we're gonna follow this ledge up, and it's a pretty rough climb, but we're gonna do it. Although it feels silent out here, we're not the only ones moving through these canyons today. After traversing the north side ledge, this final plateau comes in sight. The climb gives us elevation, and elevation gives us perspective. To the east, you can see Ute Mountain, and looking northward, the Blue Mountains and the Buttes of Bears Ears stand out against the sky. Then, after nearly half a mile of flat desert scrubland, the land falls and gives us our first view of this feature. It's a strange experience, like approaching the edge of the Crayon Canyon. There's no gradual reveal, it's just a sudden massive drop. When examining a feature like this, I try to slow down and look for clues to explain its story. At first glance, it does look crater-like, a huge circular wall, a central tower, but the first clue is in the rock itself. The layers in that central tower are perfectly preserved and identical to the surrounding wall. Same formations, same sequence. That ultimately eliminates a meteor impact. Flying above it reveals another telling detail. This formation sits directly against the San Juan River, open to the main canyon. Zoom out further, and similar features appear again and again, especially downstream at Gooseneck State Park. In fact, just upstream, the same process is unfolding right now. This isn't a crater, this is the remnant flow of the ancient San Juan River. The San Juan River used to actually flow all the way around this, and eventually the river abandoned this route. It's just like a lot of the goosenecks downstream and upstream, but this gooseneck got so extreme that it cut itself off. This landform has a name. A rincon. A rincon forms when a deeply entrenched river meander cuts so deeply into the landscape that it eventually abandons its looping bend. The river takes a shorter path, leaving behind an isolated tower of rock, a stranded core of what was once inside of a sweeping curve. Standing here on this cliff edge, I'm standing on what used to be an ancient riverbank. Millions of years ago, the San Juan flowed right at this level, then came uplift during the Laramide Orogeny, slowly raising the Colorado Plateau. Instead of wandering across a floodplain, the river began cutting downward, carving through layers of the 300 million year old Hanukkah Trail formation. Looking down at the central tower, I can see the story written in its layers. Resistant limestone benches, softer slopes, a bentonite-rich platform reaching outward like a balcony. Above it, stair-stepped ledges that feel inviting. It's all an extraordinary example of the relentless power of water, guided by uplift and shaped over unimaginable time. If you've made it this far, I'd encourage you to engage with my channel a little further. Subscribing helps a lot. And if you want to help get more educational adventures like this off the ground, you can join as a member of the channel or support me on Patreon. Thank you.