(This essay first appeared in Flyway: Journal of Writing and Enironment in November 2016. To read it on their website, click here.)

I was whaling away at a fat slab of Coconino sandstone with a single-jack sledge and chisel and noticed one of the European volunteers watching me. When the rock cleaved in two and I had set my tools to the side he said with a thick accent, loud enough for me to hear, “badass,” and then shyly put his head down and went back to wroughting his own rock. His hand was choked up the handle of his single-jack and he hesitantly tinked the four-pound hammer onto his chisel.

I smiled, remembering some five years previous, when I’d first come to work on the Grand Canyon National Park Service’s Trail Crew. I remembered watching Dowell beat at a boulder with a double-jack, and how when winded he had handed me the sledge, saying “your turn,” and nodded for me to follow the hammer-dints he’d scored into the wandering rock. I looked from him to the sledge to the rock, thinking “yeah fucking right.”

Dowell was my crew-lead for my first three seasons in the Canyon. He taught me most everything I knew about building trails in that precipitous, highly dissected, highly erodible landscape: how to run mason string to set up a worksite; how to lay out trail grade with a clinometer; how to row a rock with a rockbar; how to take the measure of a rock, split it and fit it against another to line the trail. He taught me riprap and cribbing and steps and waterbars. He taught me how to read the trail: he once pointed out a retaining wall that held up a section of the South Kaibab Trail and described how he and two others had built it, side by side, and how different their building styles were, and right away I saw the marks of the individual craftsman: one section with untrued faces and knobby with protruding deadmen, one section clean and tight, almost ashlar quality, the final section a solid hodgepodge of the two styles, and as those things go in life, once I knew how to look I never saw walls the same.

My first experiences in the Canyon had settled like sediment atop a similar and fairly solid bedrock persona: before I came to work Trails in the Canyon I’d hiked thousands of miles in the backcountry, summited dozens of peaks; built trails in California, farmed in Washington, worked construction in Alaska; and sought adventure in Africa, Asia, and South America for over two years. I liked physical labor, I liked beer, I liked whisky and wrestling, I could boast and banter and bullshit with the best of them, I knew what I was getting into on Trails, and I was getting into it because I loved it and I was good at it. In short, Dowell didn’t need to teach me how to swing a sledge; he just needed to show me that spinning it in circles against a rock would cause that rock to split.

I hefted the double-jack, my right hand near the head, my left hand down the length of the handle. I centered Dowell’s beat-line between my spread feet, then in one unbroken motion flexed my knees, swung the sledge behind my back, and arced it over my head, my right hand sliding down the shaft to join the left hand just as the sledgehead smacked atop the rock. The eight-pound hammer head bounced back into the air, the wooden helve shivered with the strain, and the impact rang my wrist bones like a bell. It felt good. I swung again. And again, and again, the air thickening with the smell of brimstone and the dull sound of steel on stone, the boulder dumbly absorbing the blows, though every strike created cracks in the stone and every further strike rooted those cracks further through the stone, until, with a last blow, the network of cracks coalesced into the dark smile of the split rock face.

I let the sledge fall to my side and, breathing hard, looked up at Dowell. He nodded and smiled.

Working on a trail crew was like that: an interweaving of instinct and education, of explicit and implicit knowledge. After all, humanoids have been using tools for four million years; Darwin surmised that our hominid ancestor’s brains enlarged as a result of hands being used for purposes other than to support the body. My simian fingers quite comfortably wrapped around the three-foot-long handle. Watching other kids on Trails swing sledges over the years, it was obvious that they, too, felt, as the famous alpinist Gaston Rebuffat put it, “that mind and muscles were fulfilling their intended function.” Everybody had their own form, evolved through the work, through their own mechanics of body and experience, through the way they went through life. Take Tim Roark. Roark had grey-green eyes and a sweet half-smile and tears shone in his eyes listening to Dylan sing “Desolation Row,” but he was also built like a tugboat, blunt in his opinions, frequently modeled his personality after John Goodman’s character in The Big Lebowski, and paid little attention to even the crew’s infrequent social graces. He insistently hated agaves because he once happened to fall on one. What Roark lacked in height he made up with intensity, and when busting a rock he’d hoist his whole center of gravity into his swing. I’d crouch by a rock with a slab-splitter and he’d rain his sledge atop it with a rhythm few others could attain or maintain.

This Dutch kid, on the other hand, was clearly terrified of crushing his single-jack into the thumb with which he clenched his chisel. But it wasn’t just that he lacked skill and confidence and familiarity with his tools, he didn’t know the rock. The Colorado carved the Canyon out of a remarkable diversity of rock: sandstone, limestone, mudstone, shale, schist, gneiss; lumpy chert nodules on the rim and slick schist flutings along the river; basalt slabs scabbing over the western Canyon’s cliffs and Cárdenas lava vomited forth in the earth’s infancy. Knowing the nature of each rock type was a vital aspect of much of Canyon life. John Wesley Powell, the first man to run the river through the length of the Canyon, noted in his journal on August 5, 1886 that: “We have learned to closely observe the texture of rock. In softer strata, we have a quiet river; in hard, we find rapids and falls.” What held true for exploring the Canyon via river held true for doing so via climbing: you had to know, generally, what rock you could trust; as there was little rock in the Canyon you could truly trust, you had to closely observe the individual rock—the presence of desert varnish, the tint of weathering, the texture of lichen—upon which you intended to place your full weight. Knowing the materials from which you were going to attempt to build a wall or line a trail was critical, especially when it came to shaping them. Muav limestone was iron-hard and wholly uncooperative; a chunk of Muav could absorb a hundred sledge blows before a crack shanked straight to the closest edge, the obdurate rock popping off in awkward, unusable pieces. If anything, Redwall limestone was even harder, damn near impossible to shape; I had learned to be careful when crushing Redwall into trail tread, as any swing of the sledge that didn’t hit the rock perfectly square could blast the uncrushed rock back into my shin. The Kaibab limestone, a friable mix of sandy limestone and calcareous sandstone, often fractured unevenly around its exceptionally hard chert nodules. The Coconino sandstone—which this Dutchman was working on—was so soft that I could rasp off its frosted sand grains with the force of a calloused finger, and thus, in the long run, wasn’t the most durable material for building trail. But one could carve it like butter.

The eastern Canyon’s 400-foot tall cliffs of Coconino sandstone are the lithified remnants of an ancient, Saharan-sized desert. The dunes in this desert were made of pure quartz sand. For ten million years wind had whisked the rounded sand grains off the top of dunes and deposited them either on the same dune’s slipface or on a downwind dune’s windward flanks. As the dunes migrated, these minute shifts in sand were preserved as distinct lamina, some millimeters apart, some feet apart, some stacked parallel, others in beveled crossbeds. Two hundred and seventy million years later, these layers are still so distinct that geologists can determine the direction of the ancient winds, just as this kid could have placed his chisel edge along one of the seams and with a few blows split his stone as neatly as opening a book.

But how was he to know? Nobody had shown him. I’d learned to read many of the signs and signatures that make up the endless tome of knowledge that is the Grand Canyon, but only after years of working and climbing and rafting, and only with the Canyon having taught me how to read them. Geology, for example. Before coming to the Canyon my knowledge of geology was virtually nil. Which is embarrassing, because unlike this Dutch kid, hailing from a land sorely lacking in the great quantities of exposed rock that often spur one’s interest in the study of the solid earth, I had no excuse: the Santa Monica Mountains in which I was raised were a geologic wonderland.

In defense of my ignorance of this fact, they are also an incredibly complicated geology, a witch’s brew of sea floor sediments and volcanics that have been severely twisted, crushed, crumpled, and folded by the shifting and settling and subduction of the North American and Pacific plates. At the Grand Canyon, one can view over five thousand vertical feet of exposed rock as easily as scrolling one’s eye’s down a chart; one’s interest in geology is piqued exactly because, for the most part, the Canyon’s strict, layer-cake sedimentary strata serves as a geologic primer: first this, then this, then this, settling atop one another oh so neatly. The overhead geological map of the Santa Monica Mountains, on the other hand, shows a tumult of differently colored splotches signifying different rock: shale, mudstone, pebble-cobble conglomerate, slag-like diabase intrusions, dramatically folded volcanics, resistant beds of coarse-grained sandstone overlaid upon less resistant beds of fine-grained sandstone, on and on.

(And, of course, most of this rock is not exposed to the same degree as is the rock in the Grand Canyon. Most is obscured by thick brush.)

As a result of how difficult it is to tell what the hell is going on, geologically, in the Santa Monica Mountains, I never really bothered. Of course, there’s also the fact that I was either too young or too busy running, climbing, smoking ganja, and drinking beer atop that geologic tumult to pay attention to the rock’s origin story; or that at the time I’d have shunned the stilted scientific terminology as an inferior epistemological approach to that of my own sensory elations. All I knew was the feel of those narrow ridges and steep slope under my bare feet and open hands. All I knew was what the mountains taught me to see; or, as at 4:31 AM, on January 17, 1994, they forced me to see.

* * *

I woke to the sound of the window not half a foot from my head shivering violently in its frame. All of my juju and gris-gris and books were shuddering off my shelves and crashing to the floor. I rolled out of bed and crouched on the convulsing floor. From down the hall I could hear the sustained shatter of glass. Outside, great flashes of light arced across the night and the air broke with the thunder of exploding electrical transformers. Everything was rattling and clattering and the earth trembled like an animal in fear.

When the shaking subsided my father, mother, and I picked our way through the broken glass and strewn clutter of our lives and made our way to the lawn. The lawn overlooks a large swath of the Pacific Ocean and the city of Los Angeles. Practically every day of my life for eighteen years I stood on that lawn and looked out at where that ocean met the shore, where the alluvial plain began and the city gridded across it in every direction. Night provided the most marked juxtaposition: the glittering, lighted city pressing against the somber, ebon ocean; on one hand the cars and buildings and life of some twelve million people and on the other hand a vast, crescent blank.

But that night of the Northridge earthquake the city was black to match the sea. The only difference between the two was the flames of a few structure fires. It was as though there were no city, had never been a city, as though giant ground sloths and mastodons and saber tooth cats still roamed the plains. It was as though the ocean had moved up to bury the basin, as it had some five million years ago. It was my first true experience with deep time; the first time I saw that the grid could be so easily extinguished, that our cities may be so short lived, that, as Robinson Jeffers wrote: “people are a tide/ That swells and in time will ebb, and all/ Their works dissolve.”

The Northridge earthquake featured some of the strongest ground accelerations ever recorded, resulting in one of the costliest seismic disasters in U.S. history—and it wasn’t even caused by the San Andreas fault, that sleeping-dragon-like force that will unleash “The Big One” earthquake that will devastate L.A. The San Andreas, that slip-strike tectonic trigger, haunted my childhood with an unsettling combination of wonder and terror that many feel while regarding the depths of the Grand Canyon.

Obsession creates suspect patterns by which to see the world, and perhaps the threads that stretched between the Canyon and the city, the threads that stitched me to both, are threads only of my own spinning. But I was pleased, and found it fitting, when I later discovered a story, among the many shifting stories with which geologists explain the creation of the Canyon as we know it, one that gives prominence to the San Andreas Fault. The theory posits that the ancestral Colorado River used to flow the opposite direction than it does now (so, to the east and north), while a smaller river—separated from the Colorado by a small mountain range—drained more or less the direction the Colorado now flows (west and south). But at some point in the last ten million years, the San Andreas Fault shuddered, significantly lowering the Gulf of California (into which the smaller river flowed). This lower terminus granted the smaller river tremendous power to eat headward, through the small mountain range, until it eventually “captured” the ancestral Colorado, reversing its flow, a process known as stream piracy. The combined waters gouged out the Canyon to its current depths.

I love that L.A. and the Canyon may have common roots in a single tectonic strain, just as my love for the Canyon is tangled in my strains against metropolitan L.A. I love that my knowledge of both required a steeping, a continuous presence, as any true knowledge does. This Dutch kid had had no such opportunity. When he looked up again, I said, “It gets easier with time” and walked uptrail to point out the lamina lines on his own rock.