learning to see: geology

I got back from a trip up into the mountains with a question about geology, because this is what always happens to me after a trek with cliff faces and talus and high elevation. I often follow up with my friend, Rick, an actual geologist, with questions about what I’ve seen, and he entertains them with a good attitude. I often think that the stories of geologists with hip flasks of whiskey must be the result of people like me, asking them continually about rocks, where they came from, and “is this a meteorite?”¹

In this case I asked if he could confirm that what I’d seen was caused by glacial action. I’d been in an area I’d never been before, and climbing up and looking back down to a floodplain a few hundred feet below my hiking path that was littered with bread loaf sized, rounded boulders of all kinds of different colorations and apparent origins, I started to imagine all of these having been shoved and piled up, bulldozed by some massive and stubborn glacier that had originally carved out the valley below. Having seen evidence of glaciers before in various places from the Tetons, Uintas, and elsewhere, I was excited about my model and narrative—even though it was based only on my few minutes overlooking the the rocky slope and flat bottom of the depression below.

Of course, I was way off base, the variety of off base that is not just incorrect, but fundamentally upside-down, starting from the wrong premise and extrapolating into more wrongness. In his kind response, Rick explained that in this region there wouldn’t have been glacial activity, and in fact the rocks I was considering were part of a much, much older flow of water and deposition of conglomerate rocks. At least I think that’s how he explained it—as I pictured him taking a swig from his flask on the other end of this email conversation—and I was delighted both with how wrong I could be and how much more interesting his narrative was.

But the part of all this that was important was in the tool that he sent me to help with the explanation, this manipulatable, interactive geologic map, overlaying topography and landmarks with the geological features at the surface, and it provides the ability to pan, zoom, tilt, and the like, but not just with the terrain but the geology, too. I immediately launched myself to where I’d stood the day before to understand his explanation, but soon after that I was panning and flying around to place my virtual feet on my home’s front steps. That’s how I ended up with this canvas upon which the geologists apparently spilled all of their geology paints:

I find this validating because when I look up from my house, while I don’t see this huge spectral array, I see a monumental collection of browns and grays, sheer walls and reposed talus slopes, sharply squared lines and twisted warpings of thick stone, all woven together at Picasso-esque angles. I can clearly see layers, but so many of them don’t just stack in the anticipated upward fashion, instead bending so that what I’d think should be horizontal layers become practically vertical. The story is powerfully felt, even before you know what the narrative is, and the image speaks of a doubly powerful, patient, earthly engine underneath.

I understand so very little of it. So, celebrating my confusion and not knowing much about the colors or the codes on this map, I twisted it around so that I could look east and up towards the mountains from my neighborhood—or at least that of a bird from above my neighborhood. This actually looks familiar to me, even though the actual view is not painted with this technicolor:

The “real” view of this would show caramel layers of the quartzite that I marvel at from my front porch. It’s upon these shelves that at least once a summer I witness a rescue operation to help hoist some misguided and/or injured soul from some precarious position. There are also rainbow stripes on this map that represent different layers of ironically gray limestone, and I’m similarly familiar with these because they make particularly poor shelves, and in fact provide precarious sheers and loose footing on a favorite trail up the mountainside. Here where I live, these contrasting formations layer upon or face one another, depending on where you look. In this case, it’s both: limestone looks across the canyon at quartzite, while at the same time it seems to be spilling from the twisted structure of quartzite that composes a knob known as Malan’s Peak.

As with so many technologies and tools, this virtual view didn’t immediately rectify my stunted comprehension of all things geological. Instead, it just showed me how little I really even see, not to mention understood. There are codes here, written by both the rocks themselves and the map makers. But this subtle turn of the map and the re-mapping in my own head was a critical step.

I understand just enough about looking into my mountains for the past couple of decades that I know what some real physical structures are and how they map to at least some of these more prominent geologically painted areas. I have names and labels, the quartzite and limestone, for example. I’ve hung around just long enough to know the limestone is younger and should be resting atop the quartzite. And, I know there are thrust faults which re-stack and shuffle this order in certain locales. I’ve put my feet on these layers to feel for myself where they’ve been turned upward and twisted, and I’ve stared up from below these cliffs enough feel that slightest amount of vertigo as I imagine an ever-so-slight strain on the landform.

I didn’t actually learn the geology from setting foot upon or staring up at these landforms, though that was important, too. Once, in southern Utah, a geologist told me and other teachers that the scientific method of the earth scientists is something like this: Observe, observe, observe, observe, observe, observe, make up a story, observe, observe . . . and so on. What’s interesting about this to me is that the “observe” isn’t so straightforward—it obviously doesn’t just reveal how things got here or even what’s there right in front of you in the first place—and the “make up” piece isn’t really as unruly as it might sound. The facts and the stories are tied to one another in an interdependence, responsible to one another. You can’t conduct a tabletop experiment on a geological mechanism, the time and scale being what they are, so the notion of a traditional scientific method (if such actually existed) is especially tenuous for describing origins of cliffs and valleys.

This is all to say that I have appreciated that I can get answers from Rick and fellow geoscientists, but what I most value is them letting me peer into how they see and think about it all. ² I get to tag along with my friend, Tyson, when he guides teachers to rock outcrops and canyons, so I can soak in some of his expertise while he helps us all to figure out what we’re looking at. All the while he points out where to direct our gaze and prompts us to look for patterns. He gives us orientation to what these different layers are as we head upstream and down through time. All the while I could understand what Tyson is pointing out and the words he was saying, but I know I’m not seeing it through his lens and with his framework. He’s played in these sandboxes a lot more than I have.

So, here I am, my geologic naïveté firmly settled in my psyche, me looking up at the actual rock formations above my house—the crumbled talus making uniform slopes off the cliff faces to the north of Taylor Canyon, twisted layers of similar material feeding into a peak I like to hike or run frequently, all framing the canyon itself that hosts twists and turns and an outcrop of limestone on the way up the south side. I see these features on my new favorite map, but at that moment in time I still felt like I’d simply been given a new tool to pair with my own observations and my quick bits of instruction.

Impressed with this new superpower ability to see these features just above my driveway, I posted that screenshot on social media and shared the interactive link to go along. After all, it only seemed fair that if this new tool was going to suck me in for hours, I should share that experience with others, and I knew of some other teachers and armchair-wannabe-geologists like me who would really find this useful. But what was particularly useful was when another geologist friend and collaborating teacher educator, Holly, pointed out in the comments:

You are seriously lucky that you have Xfgf in your backyard!

I immediately agreed, and then just as immediately I had to go look up what “Xfgf” was. I’d passed by that a hundred times and hadn’t put it into this esteemed status.

Of course. Tyson pointed out Xfgf to me just last year, and I knew this had been pointed out by other friendly geoscientists before him, including a researcher down the hall who is literally the cited expert on this and related layers. This is part of the “Farmington Canyon Complex,” which is the really old basement of these layers that make up our mountain range. It just so happens that these pieces of the foundation are revealed in some sections of the range, if only you know what you’re looking at. I’d never put it together that it was right here at my doorstep; or at least I hadn’t appreciated this in just the right way until Holly made the random comment.

This was a pivotal prompt in my geology learning. I’m about to make the case that my learning of geology isn’t a straightforward process, and I don’t think that there’s any simple, linear process by which to really see geology in an authentic way. For me, I needed to have a combination of some orientation (Tyson explaining ages of layers and the faulting), a model to help orient me (the map and geological layering that I could re-see in this virtual manner), a few answers and modeling of how geologists put these ideas together (Rick’s patient answers and encouragement), all of which set me up to be ready to see the Xfgf that Holly pointed out.³

That Farmington Canyon Complex is not just “old,” but crazy old, billions of years old rather than the cute hundred of millions of years old of the Tintic Quartzite just above and the still younger limestone above that. And yet, that “young” limestone is staring across an open canyon and that ridiculously old Farmington section on the other side, line of sight and same elevation. It’s like putting a preschooler with a 100-year-old in the same classroom. Except it’s not like that at all, as these are completely different compositions. The Farmington stuff is varied, but largely dotted and oriented with sparkly recrystalized minerals squished about from their original igneous form, while the limestone is an old seabed, drab and uniform gray that’s concretized. The quartzite in between is squished sand, now caramelized after it’s been compressed and twisted, uplifted and revealed.

I “knew” a lot of these facts before, but now I was setup to understand them. It finally came into comprehension when I went on a run.

A run is a normal outing for me every day or so, placing my feet on the trails that skirt and intersect with these layers. We’re fortunate in that not only do these layers shape the landscape, but some nice trim work was done recently (tens of thousands of years ago) by the predecessor to Great Salt Lake, leaving behind shorelines along these mountains that make great paths for trails that have long, level stretches. If you look out across the horizon around Great Salt Lake, these ancient edges sometimes pop out in high relief like the edge of a bathtub.

This particular run was from North Ogden back to my home in Ogden proper, essentially ending at Taylor Canyon. I ran along this old shoreline, getting a review of what I’d been looking at from below and on maps. Running from north to south, I found myself at one point running among slick gray limestone, then into the caramel quartzite, and then—because I was now primed to look for it—the crystaly gneiss that I knew was part of the basement. My great revelation was that I was running at a nearly constant elevation (once I got to that level) but tracing back through time from young to old to very very old. That is, the layers are tipped, and as I started to realize this in a new way, on my own two feet for ten miles, I had the chance to not just be told this, but to feel it. As I started to approach the mouth of Ogden Canyon (one drainage to the north of Taylor Canyon), proud of myself for understanding what I was standing on, I looked across the canyon to see limestone. That is, I was standing on the oldest stuff and looked across at the youngest stuff.

This is the first time in my life that I really felt what a thrust fault is. I mean, I knew what they were because I’ve been told, but I put myself in a terrain, with the right amount of orientation, and (most important) with a sense of what to look for. These patterns are obvious, once you know to look for them.

Much to Rick’s chagrin, I imagine, I can now start to come up with my own models for how different canyons have formed. These canyons that have different strata on each side, old gneiss across from young limestone, must have been faulted long ago, and welcomed water to run through and further erode them. But a canyon just a bit farther south, Strong Canyon, has schist on both sides, also a layer of the metamorphosed goo of the Farmington Canyon Complex. So, while the water pouring through could be prompted by faulted terrain farther above, this particular canyon is largely a result of the force and patience of water. Strong Canyon, come to think of it, is much narrower than the canyons that seem to have resulted from faulting. Strong Canyon is a place I’ve trekked up a hundred times as well, but I never appreciated its contrast to the other canyons until these pieces started coming together, I started to realize what to look for, and that in turn prompted me to look for new things.

I’ve since spent multiple runs and walks not just paying attention to footing and on alert for rattlesnakes, but watching the rocks and cliffs change. I feel myself go back and forth through time, and I’ve started to pick out that there are layers within the layers—the Farmington stuff has a range of colors from grays to reddish to black, but all with that speckling, except where its foliated schist with shiny plates of mica all lining up. Admittedly, I don’t really understand how these different layers within the formation go there, where their colors originated, or what it means to see the different crystal formations, but now I know enough to see the differences and to ask these questions. And I’m beginning to feel and expect these sublayers as I traverse. I now can see enough to be able to look for new phenomena and patterns.

Finishing a run and getting to the spill of debris that fans out from Taylor Canyon, I can see and identify the individual components of this graveyard of boulders and smaller rocks. Quartzite here, gneiss there, each looking at one another as if they had come from completely different universes and happened to get dumped off on the same curb. They are a billion years separated in formation, but now piled together in the same party. I was marveling at this idea, finishing my run down the block and then realized, right there in my own front yard, these same two types of rocks were lying right there where I coil my garden hose. They’ve been telling me part of this story for as long as I’ve lived here. It’s only now that I had the wherewithal to read it.

In fact, it was only now, at the end of my run today, that I realized that at this fan below the mouth of the canyon with piles of quartzite and gneiss that there is no limestone here, even though it’s prolific higher up in the same areas that the other two layers are. Now, looking at it all in new light, I had the sense that this tells me something about how erosion works on these different layers. The gneiss and quartzite can roll and tumble this far over time and stay intact; the limestone, while I see it underfoot and polished by treads of boots and bikes farther up the slope, do not endure to make it farther down. So this tells me something about the fundamental integrity of limestone compared to the other metamorphic rocks.

Is that right, Rick?

Maybe Rick will reply with his usual encouragement. Or maybe he’ll take a swig from his flask. Maybe he’ll tell me I’m right this time. Or maybe not, and that will be fantastic. I’ll have more maps to look at, more staring to do, and more runs to go on.

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1. For the record, it’s never a meteorite. ↩
2. What I most love about John McPhee’s Basin and Range is not just the geology or the characters, but how the author gets a sense for how they look at and think about their study. It’s one of my favorite books, and all of this experience has made me realize I should return to it. ↩
3. I regularly assign an essay, “Learning to See” by Samuel Scudder, written in the late 1800s and documenting his introduction to graduate school. This introduction looks a bit like a hazing ritual crafted by his advisor, Louis Agassiz, in which Scudder is left with a dead fish to observe for days on end. The lesson is that he had to learn to see in new ways before he could recognize the importance of seemingly simple characteristics such as the symmetry of paired organs in fish and so many other organisms. ↩