Reflections of a Road Warrior
I began my journey in the overpopulated East, where the Appalachian Mountains—formed more than 250 million years ago—now lie subdued beneath layers of human settlement and urgency. The roads here are crowded, the pace performative. Drivers jockey for position, not just to arrive but to assert. In this terrain, driving is a social act, a negotiation of space and dominance. I obeyed the speed limits, but the pressure to conform was palpable. The land, ancient and eroded, seemed to whisper of restraint, but the people moved as if chased.
Crossing the Great Plains, the landscape flattened into a vast, glacially weathered expanse. Once grasslands, now farmland, the terrain offered little variation—just endless repetition. Here, the temptation to speed was not about competition but escape. The monotony of the land invited dissociation. Cruise control became a crutch, and the mind wandered. I found myself accelerating not out of urgency, but out of boredom. The road stretched like a taut string, and I felt the pull to snap forward. But I resisted. I slowed down. I began to see the land not as obstacle, but as place.
In the intermontane basins and across the Rocky Mountains, the terrain shifted again. The Rockies, surprisingly, offered no drama. I crossed them with nary a whimper. The basins between ranges were long, subdued, and emotionally neutral. Driving here felt mechanical, almost meditative. The land flattened my urgency. I became an automaton, moving through space without resistance. It was peaceful, but also forgettable. The road no longer demanded attention—it simply received it.
Then came western Montana, Idaho, and Washington. The youthful peaks struck like a cymbal crash. Steep grades, winding highways, and sudden elevation shifts pierced the monotony. I was exhausted—metaphorically speaking—by the mind-numbing landscape behind me, and now the terrain demanded vigilance. Driving became reactive again. The land had changed, and so had I. I was no longer cruising; I was contending. The road had become a teacher.
Less than a mile from my motel in Missoula, I witnessed a collision—a junker sports car and a delivery van, both likely violating traffic laws. The vehicles bounced like Tonka Toys, absurdly intact despite the violence. The driver of the wrecked car tried to restart his mangled machine, as if denial could override physics. Traffic paused, sighed, and resumed. No one panicked. No one intervened. The system absorbed the chaos and continued. It was a once-in-a-lifetime moment, and I had a front-row seat.
This scene encompassed many of the behaviors I’d observed across the country. Reckless driving wasn’t confined to high speeds—it occurred at low speeds too, often in familiar places. We rarely pause to see these events as inevitable outcomes of behavioral contagion, misaligned urgency, and systemic detachment. The stoic traveler observes without absorbing panic, recognizing the choreography of modern motion and its refusal to acknowledge consequence.
As I drove westward, I began to notice a pattern—not just in the terrain, but in how people moved through it. Flatness bred velocity and boredom. Elevation restored awareness. Geological youth correlated with behavioral tension. The land was not neutral. It shaped urgency, perception, and emotional posture. I had come to recognize a love-hate relationship with living in such a large country. The vastness invites freedom, but also fatigue. Driving is, above all else, boring—especially at highway speeds. But boredom is part of the lesson.
And then came the most important realization: Let local traffic pass; their urgency is not yours. This became my mantra. Most of the vehicles around me were not crossing states. They were running errands, commuting, performing routines. Their urgency was performative, not purposeful. I was on a different journey. I didn’t need to match their pace. I didn’t need to compete. I could let them pass. I could observe without absorbing. I could drive with intention.
This awareness led, fitfully, to acknowledging the inescapable control of the land over our minds and emotions. The terrain modulates behavior. It governs how we move, how we think, how we feel. The road is not just a conduit—it’s a medium. And to cross America solo is to engage with that medium fully. It’s to see the choreography between geology and psychology, between motion and meaning.
I did not enjoy driving fast. I found it fatiguing, disorienting, and performative. Slowing down was not just a mechanical adjustment—it was a philosophical one. It allowed me to appreciate the act of covering ground, to see the land as layered text, to learn in a hands-on way about geological and societal history that no Wikipedia article could convey. I stopped at unexpected locations. I absorbed stories sedimented in stone and soil. I saw how the land shaped settlement, movement, and memory.
I wish I’d had more time. My mind couldn’t keep up with the rapid pace. I experienced a kind of jet lag, even though I never left the ground. The body moved faster than the mind could metabolize. Reflection lagged behind experience. But that lag was instructive. It revealed the limits of perception, the need for pacing, the value of restraint.
In the end, this drive was not just a crossing—it was a reckoning. It was a slow-motion confrontation with the land, with behavior, with self. I began in the roots of the Appalachians and ended in the youthful peaks of the Northwest. I moved from assertion to observation, from urgency to awareness. I let others pass. I slowed down. I listened.
And the land spoke.
Acknowledgment
This essay was written by CoPilot after an extensive conversation, which it reduced to this piece. I accept full responsibility for the contents. The photographs are all real, taken by me along the way.
Rock Creek Park, Maryland: Early Cambrian Marine Sediments
Figure 1. This post comes from the NW end of Rock Creek Park, which begins in Washington DC. I discussed volcanic rocks and sediments there in a previous post. The star indicates home, so this is another local trip, examining some rocks we’ve seen before although by a different name. The inset map shows Lake Frank and the dam that created it. This is a flood control dam built in the sixties. The dash line shows our walking path, which followed the lakeshore a little, but climbed several ridges as we crossed a small creek that feeds the NW end of the lake.
Figure 2. Photo of Lake Frank from the dam. The main inflow (North Branch Creek) is to the right at the other end of the lake in this image. The outflow exits through the structure near the dam and continues a short distance before joining Rock Creek and flowing to DC.
Figure 3. This exposure of Sykesville Formation rocks (538-511 Ma) is tilted about 30 degrees in a westerly direction, as indicated by the yellow line. It is obscured by shadows, so I took a photo of a loose sample lying nearby (inset). The foliation is considered to be tectonic rather than original (according to Rock D). This unit is about 9000 feet thick and is uniformly conglomerate with metasedimentary clasts. As with any sedimentary rock, however, there is going to be spatial variability. These rocks are contemporary with Harpers Formation I examined at Bull Run Nature Preserve. However, the Harpers Formation contains interbedded schist (mud), quartzite (sand), and conglomerate (gravel) in a coarsening upward trend.
Figure 4. (A) Photo of loose boulder along the trail near Fig. 3, showing what looks like quartz filling a vein in a host rock that seems to contain some clasts, although quartz has penetrated pretty thoroughly. The dash lines are meant to suggest where the quartz is less massive; there are also several locations where a thin layer composed of fine-grained, gray material is found. Not a great example. (B) This is a better example, but the trees weren’t cooperating. The arrows point to irregular clasts contained in a gray matrix. However, the gray could be a weathering color.
SUMMARY
Overall, I’d say that the Sykesville Formation is pretty similar to the Harpers Formation at Bull Run Nature Preserve (~40 miles SW), including their radiometric ages. These rocks represent the erosion of highlands for more than 20 million years and, if the coarsening upward sequence seen at Bull Run NP is any indication, the source moved closer to VA and MD. This suggests that mountains were still rising during this period and hadn’t peaked yet. I’m certain that I’ll eventually encounter more of these rocks. The source of the metasedimentary clasts contained in the Sykesville Formation would have been previously buried sediments that were metamorphosed during burial and (probably) deformation.
There are several cycles visible here: (1) deposition of sediments during the Precambrian, with subsequent burial, deformation and exhumation over tens of millions of years; (2) these rocks were exposed to the atmosphere and weathered during the Cambrian period. Some particles collected on the seafloor to form the Sykesville and Harpers Formations not far from the source. These were buried and slightly metamorphosed; (3) they are now being exposed as the overlying rock has been removed by erosion.
Around and around we go …
Geological Cycles at Wolf Trap National Park
Figure 1. (A) Wolf Trap National Park for the Performing Arts is located about twenty miles west of Washington DC, near several parks I’ve discussed in previous posts, especially Great Falls National Monument. The geology of the area is dominated by Neoproterozoic-to-Cambrian (1000 – 511 Ma) metasedimentary rocks that originated in oceanic environments near rapidly rising mountains (e.g., a volcanic island arc). The dates are from the time of metamorphosis, which is why they give such a long time span. Taking into account the accuracy of the dates in general, this region was undergoing erosion with the resultant sediment buried in marine trenches, probably near a subduction zone, for hundreds of millions of years. The majority of the material would have been mud. There would have been hiatuses (perhaps an ocean basin briefly emerged), but such detail is lost to us after so long. (B) This map of Wolf Trap Park shows the trail we followed. The map doesn’t show topography, but the ridges are short, with maximum relief less than 100 feet. Wolf Trap creek enters from the west (left side of panel B) and flows through a wetland area (indicated by blue ellipse) before meandering a little and following the east side of the valley.
Figure 2. View of Filene Center from the SW side of our trail loop (see Fig. 1B), showing typical topographic relief at Wolf Trap park.
Figure 3. View of Wolf Trap creek where it enters the valley (Fig. 1B), showing boulders of Precambrian schist to be blocky–eroded nearby and gravitationally slid into creek but were not transported. These recently exhumed blocks are covered by Quaternary fluvial sediments, which are visible along the left side of the creek.
Figure 4. Large block (less than 6 feet in diameter) of schist that has been moderately weathered in place. Note the thin bedding (fissility) between thick layers with a conchoidal fracture pattern (center of image). This is the upstream side, which is pockmarked by rolling and bouncing boulders during high water. Mud becomes schist when buried deeply, retaining the lamination of the original fine-grained sediments, but remineralizing to familiar clays easily at the surface. Mud to schist to mud.
Figure 5. Meander in Wolf Trap creek along the north side of the park (see Fig. 1B), where a shallow pool of quiet water collects between runs (turbulent creek segments).
Figure 6. View looking upstream from a pedestrian bridge crossing Cthse Spring Branch, a tributary crossing our trail (dash line in Fig. 1B) before it joins Wolf Trap creek (NE side of trail in Fig. 1B). The boulders are smaller than downstream (Figs. 3 and 4), and their long axis are aligned with the stream flow. These angular blocks are sliding along on a stream-bed comprising miniature versions of themselves (note the clear view of the bottom in center of image). Even gravel and pebble-sized particles are platy because of the characteristic fissility of schist.
Figure 7. This photo dramatically reveals the effect of water on erosion.
Figure 8. This image is one I’ve seen too often here in northern VA. The sewer systems frequently follow streams because they are low points and run downhill (a good property for a sanitary system). However, when stream levels exceed expected values, the system is compromised and raw sewage can be released into the environment.
Summary. Over a billion years ago, this area was submerged beneath an ocean or marginal sea. Distant mountains eroded rapidly in a time before land plants. Vast quantities of sediment accumulated in layers of erosional debris that were subsequently buried by younger sediment. Between a billion and five-hundred million years ago, these sediments became rocks that were subsequently deformed as continental plates collided. They didn’t melt, however, and survived the cataclysm relatively unharmed, becoming schist and related metasedimentary rocks. For the last 200 million years, they have been slowly working their way to the surface as younger rocks are removed by water erosion in streams like we see all throughout NoVA. They are now exposed to the elements and are weathering to form new layers of sediment in the Atlantic Ocean, beginning a new cycle.
Washington Monument State Park, MD: Familiar Cambrian Metasediments
Figure 1. Looking west from Washington Monument, atop the Blue Ridge in Maryland. The valley is equivalent to the Shenandoah Valley in VA (see Fig. 2), but I couldn’t find a map with it labeled. The Appalachian trail follows the ridge through MD; we encountered it a few miles south of here in a previous post. We expect to see some of the same Proterozoic-to-Cambrian (2500-500 Ma) metasedimentary rocks here that we saw before, in addition to a surprise from an older post.
Figure 2. The field site. Washington Monument is indicated by the purple circle and arrow in the large map. The first inset map shows the geology around the monument. Note the mismatch in geology from different quadrangles; this must be a problem with either the data or Rock D, but the units (indicated in the smaller inset map to the right) were consistent when I clicked on a point. My home is indicated by the star, so you can see we haven’t traveled far. ATWC refers to the Appalachian trail at Weverton Cliff, MD, which I recommend you read to get some background. BRNP represents Bull Run Nature Preserve, which I posted last year. The geological legend for the detailed inset map is at the bottom of the figure. Note that Ma stands for a radiometric age of one-million years; this age is indicative of cooling below the threshold to set the atomic clocks within the minerals, but sedimentary rocks can’t be dated this way. Therefore, these are dates when deep burial and/tectonic deformation/magmatism ceased (i.e. when an orogenic period ended).
Figure 3. Rubble near the monument that resulted from in-place weathering of Weverton Formation rocks (Cw1 and Cw2 in Fig. 2). All of the weathering products (e.g. clays and carbonates) have been washed away, leaving large slabs (~6 feet) piled up. This is a common feature of rocky knolls with good drainage.
Figure 4. (A) Outcrop of older Weverton formation rocks (Cw1 in Fig. 1), revealing weathered material below and boulders on top. This outcrop contains cross-bedded layers on close examination. (B) Photo of a block of Cw1 used in the monument , which shows the crossbedding better than panel A because a fresh surface was cleaved during a recent repair of the 30-foot tower. The color is important: green sedimentary rocks like these represent marine environments, where there is less oxygen; sedimentary rocks deposited in rivers tend to be reddish because of oxidation (rusting) of Fe-containing minerals. These are probably shallow marine sands.
Figure 5. (A) Quartz in a vein (<1 inch thick) from near the monument. Note that the cross-bedding is very similar to Fig. 4 but more weathered. (B) Less-common view of a quartz vein seen obliquely, showing the surface that was against the country rock. These veins would have been injected during a period of magmatism, sometime between 2500 and 511 Ma; I can’t be more specific because I don’t know exactly where the radiometric ages were measured within these rocks. However, the Weverton formation is approximately 4500 feet (1.4 km) thick here; thus it’s possible that these rocks were deposited episodically during this immense time interval; but no unconformity (i.e. erosion or non deposition) is mentioned in RockD.
Figure 6. View looking east from the Appalachian Trail, showing the terrain typical of the Appalachian foothills. To the left of center, outcrops of Weverton rocks (Cw1 and Cw2 in Fig. 2) can be seen.
Figure 7. (A) Boulder (~2 feet across) of arkose, revealing angular clasts of rock fragments in a sandy matrix. (B) Poor outcrop of conglomerate with rounded rock and quartz in a similar, sandy matrix. Comparing these images to Fig. 4 shows the variability of sedimentation (and thus depositional environment) during relatively short time intervals (say … tens of millions of years, for example). This kind of variability implies changing sediment sources, possibly caused by tectonic uplift (with magmatism) to the east.
Figure 8. This figure is from the Bull Run Nature Preserve field trip. It is a schematic of how layers of sedimentary rocks (shown in different colors) can slide over one another along thrust faults. This process results in stacking of similar sediments, making stratigraphic analysis of sparse field data problematic. The rocks on the left are sliding upward to the right along a series of thrust faults (dashed line). At Bull Run Nature Preserve, a fault like this could be identified by older rocks clearly being stratigraphically higher than younger ones. That isn’t the case at Washington monument, where the interleaved rocks (blue and green) are too similar in lithology and age to be differentiated.
SUMMARY
The thrust fault labeled in Fig. 2 has been confidently identified (represented by a solid line), no doubt through more investigation than I was willing to spend time on. This unnamed fault underlies the northern Blue Ridge, and marks the beginning of the Valley and Ridge province; the Blue Ridge was thus an anomaly, which has been identified as a belt of older rocks thrust over younger ones about 500 million-years ago, when the supercontinent of Pangea was being created.
We have followed the Weverton formation through time (2500-485 Ma) and space (more than 40 miles). During this unimaginable interval, this small piece of the Earth’s crust has moved thousands of miles. Only the last 500 my of its journey is known with any confidence. This tectonic plate has been carrying these sediments to unknowable latitudes, colliding with immovable objects while spreading the remnants of mountain ranges that are now forgotten, deconstructed by the irresistible power of water, wind, ice and time.
Some things aren’t meant for us to know …
Timothy R. Keen 
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