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Dinosaur Ridge

One-line summary: The eastern flank of the Dakota Hogback monocline ~20 mi west of Denver, where two trackway-rich sandstone beds — Late Jurassic Morrison Formation (~150 Ma) sauropod prints and Lower Cretaceous Dakota Formation (~100 Ma) iguanodontid prints — bracket roughly 50 million years of dinosaur history along a single mile of tilted road, plus the original "Bone Wars" quarry that gave the Morrison Formation its name.

Dinosaur Ridge

One-line summary: The eastern flank of the Dakota Hogback monocline ~20 mi west of Denver, where two trackway-rich sandstone beds — Late Jurassic Morrison Formation (~150 Ma) sauropod prints and Lower Cretaceous Dakota Formation (~100 Ma) iguanodontid prints — bracket roughly 50 million years of dinosaur history along a single mile of tilted road, plus the original "Bone Wars" quarry that gave the Morrison Formation its name.

Scope note: this template covers steps 1–3 of the adventures pipeline (identify, support Maxine's research, shape goals). The deliverable webpage

  • video at step 6 is Maxine's own work — don't scaffold it here.

Links & Maps

Official:

Maps:

Reference & background:

Site geography (read before planning the day)

Dinosaur Ridge isn't one site — it's a ~1-mile road cut through the Dakota Hogback with numbered interpretive stops on both flanks. The hogback is a single ridge of resistant rock standing 200 ft above the surrounding plains because the Laramide orogeny (~70–40 Ma) tilted the entire Front Range sedimentary section ~60° to the east. As you walk W along Alameda Pkwy from the Discovery Center, you cross:

  • Younger rocks (east, plains side) — Cretaceous shales and the Dakota Sandstone (the cliff-forming ridge itself; this is the Dakota trackway layer).
  • Crest of the hogback — the Dakota Sandstone caprock, ~100 Ma.
  • Down the west flank into older rocks — Cretaceous shales descending into the Morrison Formation outcrop (the sauropod trackway is on the west side, ~150 Ma).

So as you walk west you go back in time through ~50 million years of rock per ~1/2 mile of road. This is the cleanest stratigraphy-in-microcosm walk in the Front Range, and the whole point. The bus tour is essentially a moving lecture on this transect.

The Morrison "Bone Bed" (Arthur Lakes' original 1877 discovery quarry) is a separate stop within the same park; the working bone-extraction pits are a few hundred meters from the trackway walls. The Triceratops Trail (a separate trail on the western side of the hogback, near Rooney Ranch) is owned by the same nonprofit but is a 5-min drive — it's the back-side of the hogback exposing the Laramie Formation, with mammal and bird tracks from ~68 Ma.

Must-See / Big Items

Ranked by payoff. Order assumes you walk it east-to-west or take the bus loop.

  1. Morrison Formation main trackway (west side of the road cut) — ~150 Apatosaurus prints in a single bed, with at least four trackmaker species discriminated by size, gait, and toe-count. This is the Late Jurassic ~150 Ma. The prints are positive relief (raised) on the underside of a sandstone bed — what you're looking at is the underside of the layer that was deposited into the original footprints. Read the placards on whether you're looking at the trackmaker's right or left foot, and whether the animal was walking or running (stride length ÷ hip height).
  2. Dakota Formation trackway (east side, just below the ridge crest) — Lower Cretaceous ~100 Ma. Iguanodontid (large ornithopod, three-toed) and possible ornithomimid (smaller, narrower) prints, plus invertebrate burrows (Skolithos-type) and ripple marks. The same surface preserves a beach environment: tracks parallel to ancient shoreline, ripple marks indicating wave direction. This is the Western Interior Seaway shoreline.
  3. The Bone Bed / Lakes Quarry — the spot where Arthur Lakes, a Wesleyan-trained geologist working at the Colorado School of Mines in Golden, found massive bones in 1877 while exploring the hogback. He sent samples to both O.C. Marsh (Yale) and E.D. Cope (Philadelphia) — the Marsh-Cope letters at this site triggered the "Bone Wars." The original Apatosaurus, Stegosaurus, and Allosaurus type specimens came out of this rock. The pits today are interpretive — the prize specimens are at Yale Peabody and the Smithsonian.
  4. The Visitor Center exhibits (Main building) — fossil casts, the touch-table with a real Morrison sauropod vertebra, and the relief model showing how the Dakota Hogback fits into the Front Range monocline structure. Hit this before walking the road so the stratigraphy makes sense in 3D.
  5. The Discovery Center (east-side building) — more recent, more child-friendly, but also has the best displays on the Western Interior Seaway, the Cretaceous-Paleogene boundary (~66 Ma), and the geology of the Front Range uplift. Ideal post-walk synthesis stop.
  6. The bus tour with a docent — yes, you can walk it, but the docents will tell you which trackway is which dinosaur, point out the ripple marks and burrows your eye won't find unassisted, and key the geology to the landscape. 45 min. Worth $15 even for someone reading the placards.
  7. Triceratops Trail (separate, ~5 min drive) — on the west side of the hogback at the old Rooney brick quarry. Late Cretaceous Laramie Formation (~68 Ma — just before the K-Pg boundary). Mammal tracks, bird tracks, ceratopsian prints. Less famous than the main ridge but tells the "what was here right before the dinosaurs went extinct" story.
  8. The "Creation Rock" overlook — the rim of the hogback gives a clean north-south view down the strike of the Dakota Hogback all the way to Red Rocks (4 mi south). You can see the same tilted Fountain Formation red beds at Red Rocks from here.
  9. The placards on Laramide structural geology — easy to skim, worth a slow read. These explain why a sandstone deposited horizontally is now tilted 60° east.

Stretch goals (do if time allows):

  • Morrison Natural History Museum (1 mi south in downtown Morrison) — small but excellent local museum with original Lakes-era fossils and the only known Stegosaurus baby tracks.
  • Red Rocks Park — 4 mi south, same Dakota Hogback, dramatically different exposure (the Fountain Formation, 150 million years older). Separate adventure doc (red-rocks.md) — easy combine into one day.
  • Colorado School of Mines Geology Museum in Golden (~10 mi N) — Arthur Lakes' home institution; world-class minerals + the Morrison material that didn't go east.

Research angles for Maxine

The research is hers — list questions to investigate and sources to start from, not answers. Pitch above grade level.

Hook into Maxine's current interests: (ask before finalizing — what is she into right now? bend the questions to that. If she's currently on a paleontology kick, push the trackway-biomechanics + bone-wars-personalities angles. If it's structural geology, push the Laramide monocline + Front Range uplift thread. If it's writing/people, push the Marsh-Cope-Lakes triangle. If it's math, push the trackway-stride-length-to-speed calculations.)

Questions worth chasing:

  • Science (sedimentology): Why are the Morrison Formation trackways preserved at all? What does it take to fossilize a footprint — the right substrate cohesion, the right depositional event right after, the right diagenesis? Why is the Morrison so productive globally (it underlies parts of 13 US states) — what was the depositional environment? Floodplain? Lake margin? Distal alluvial fan? Why no marine fossils?
  • Science (stratigraphy): The Morrison (Jurassic) and Dakota (Cretaceous) are separated by ~50 million years and an unconformity. What's missing? Why is the gap there? What does that mean about what was happening in this part of North America between 150 and 100 Ma? (Hint: the Western Interior Seaway was just starting to flood in.)
  • Science (structural geology): The Dakota Hogback is the textbook eastern flank of a monocline — sedimentary rocks draped over a basement uplift. What is the Laramide orogeny, when did it happen (~80–40 Ma), and how does it differ mechanically from the older Sevier orogeny (thin-skinned thrusting) to the west? Why does the Front Range have basement-cored uplifts but the Wyoming/Utah thrust belt doesn't?
  • Science (paleontology): Apatosaurus, Diplodocus, Camarasaurus, and Brachiosaurus all coexisted in the Morrison environment. How did four giant sauropods avoid competing? (Niche partitioning — neck length, tooth wear patterns, isotope signatures.) What does the trackway evidence say about herd behavior — were they walking together or sequentially?
  • Science (biomechanics): Given a sauropod trackway with measurable stride length (S) and an estimated hip height (h), use the Alexander (1976) equation: speed ≈ 0.25 × √g × S^1.67 × h^-1.17 (where g is gravity). What were these Apatosaurus actually doing — walking, trotting? How does that compare to estimated running speeds?
  • Science (paleoclimate): The Morrison environment was semi-arid with monsoonal floods; the Dakota was a humid coastal floodplain at the edge of the Western Interior Seaway. What does pollen + leaf-margin analysis + isotope data tell you about temperature and CO2 during each? Is the Mesozoic "greenhouse Earth" framing oversimplified?
  • History (Bone Wars): Arthur Lakes' 1877 letters to Marsh — what did he write, and how did Marsh respond? Why did Marsh and Cope hate each other (it goes back to the 1868 Haddonfield, NJ Elasmosaurus head-on-wrong-end incident)? What did the Bone Wars cost American paleontology (rushed publications, deliberately damaged specimens, double-naming) and what did it gain (the establishment of vertebrate paleontology as a US discipline)?
  • History (institutions): Arthur Lakes was on the Colorado School of Mines faculty; he was also an Episcopal deacon and a competent watercolorist. Trace his life: Wesleyan → Colorado → Mines → Dinosaur Ridge → his post-1880 work documenting Colorado mining geology. How did one geologist, who never had a PhD, contribute to three different fields?
  • History (Morrison the town): Named after George Morrison, a Scottish stonemason who built a quarry there in the 1860s. The Morrison Formation is named after the town. How does a place name become a formation name in geology — what's the type-locality convention, and who gets to name a formation?
  • Writing: Pick a 24-hour window in the 1877 Bone Wars (say, the day a telegraph reached Marsh about Cope's competing dig at Como Bluff). Write it as a short story from one of the three points of view: Lakes (the local geologist), Marsh (the Yale establishment), Cope (the eccentric Philadelphia outsider). Constraint: only use facts documented in the actual correspondence — no invented dialogue.
  • Math: Stride length on the main Apatosaurus trackway is ~3 m. Apatosaurus hip height ≈ 3 m. Plug into the Alexander equation. Speed? Now compute speed for the smaller Camptosaurus tracks on the same trackway. What does the speed-mass relationship look like across the trackway makers?
  • Math (Laramide): The Front Range basement is uplifted ~3 km relative to the basin to the east. The crustal shortening required to produce this in a basement-cored uplift is small (~5–10 km horizontal shortening over ~200 km width). Compute the strain rate if this happened over 40 Myr. Compare to modern measured plate convergence rates (cm/yr).
  • Math (Bone Wars accounting): How many new dinosaur species did Marsh and Cope each name during the peak Bone Wars years (1877–1892)? How many are still valid today vs. synonymized? What does that tell you about the cost of speed-publishing in science?
  • Art: Arthur Lakes himself produced watercolor sketches of his Morrison quarry — they're in the Yale Peabody archives and online. Study his field-sketch technique. Then go to Dinosaur Ridge and produce a comparable graphite or watercolor field sketch of one of the trackway walls. Annotate it the way a 19th-century field geologist would (formation name, dip and strike, scale, north arrow).
  • Art (paleo-art): Compare Charles R. Knight's late-19th-century Apatosaurus paintings (tail-dragging, swamp-dwelling) to modern 2020s reconstructions (tail held horizontal, terrestrial, herding). What changed about the science, and what changed about the cultural image? Sketch your own Apatosaurus from the trackway evidence alone, without referring to any reconstruction.

Starting sources (not exhaustive — she'll find more):

  • Friends of Dinosaur Ridge education portal: https://dinoridge.org/learn/
  • USGS Geology of Dinosaur Ridge open-file: search "USGS Dinosaur Ridge Morrison geology"
  • Url Lanham, The Bone Hunters (1973) — the standard popular account of the Bone Wars
  • Mark Jaffe, The Gilded Dinosaur (2000) — newer Bone Wars history
  • Robert Bakker, The Dinosaur Heresies (1986) — the warm-blooded-dinosaur argument; Bakker worked Morrison sites
  • Alexander, R.M. (1976). "Estimates of speeds of dinosaurs." Nature 261: 129–130 — the trackway-to-speed equation, foundational
  • Yale Peabody Museum, Marsh archive (digitized portions online): https://peabody.yale.edu/collections/archives
  • Denver Museum of Nature & Science vertebrate paleo research: https://www.dmns.org/science/our-scientists/
  • Colorado Geological Survey: https://coloradogeologicalsurvey.org/

Observable field goals

Goals Maxine can verify or document in the field at step 5 (confirm & document). Concrete things to look at, count, measure, identify, or photograph — not vague "learn about X."

  • Find the Morrison main trackway. Photograph one Apatosaurus print with a scale (her hand, a ruler). Measure stride length (heel of one print to heel of the same foot's next print) and pace length (heel of left print to heel of next right print). Note whether the prints are natural casts (positive relief filling the original footprint, what you mostly see here) or true tracks (negative relief on the original walking surface).
  • At the Dakota trackway: identify and photograph (a) one iguanodontid three-toed print, (b) one set of ripple marks indicating ancient flow direction, (c) one Skolithos-type vertical burrow. Note which direction the ripple marks indicate the waves were coming from.
  • Photograph the unconformity between the Morrison and the Dakota — find the contact on the road cut and document it. Note any change in rock color, grain size, or bedding character across the boundary.
  • On the hogback ridge: take a compass dip-and-strike reading on the Dakota Sandstone. Compare to the placard's value. Note the dip direction (should be E or NE, ~60°).
  • At the Bone Bed quarry: photograph the placard showing what came out, then identify the rock unit it came from (Brushy Basin Member of the Morrison Fm). Note the rock color and any visible bone fragments — much of the bone has been removed but float pieces persist.
  • Take the same general north-south landscape photo from the top of the hogback at Dinosaur Ridge AND from the top of the hogback at Red Rocks (4 mi south). The two photos should show the same continuous ridge viewed from two points — the structural continuity of the Dakota Hogback.
  • Sketch (graphite or watercolor) one trackway wall in the field, annotated as a 19th-century field geologist would (formation, dip/strike, scale, north arrow, your name and date). Aim for accuracy over beauty.
  • Document the elevation reading (phone or GPS) at the parking lot and at the highest interpretive stop. Note how Maxine feels at ~6,200 ft on this first day in Colorado — pulse rate, breathing, hydration. This is the altitude baseline for the rest of the trip.

Suggested itinerary

Half-day plan. Pair with Red Rocks for full day, or with Denver Museum of Nature & Science for a paleo-focused day.

  1. 8:00 am — leave Denver-area lodging. Drive ~30 min to Main Visitor Center.
  2. 8:45 am — Visitor Center exhibits + bus-tour ticket purchase (or walk-up). If walking: pick up self-guided map. Morning light is the trackway-photo prize — don't dawdle indoors.
  3. 9:15 am — Bus tour OR walk west along W Alameda Pkwy. Morrison main trackway first (45 min), then continue uphill to the Dakota trackway (30 min). Read placards.
  4. 11:00 am — Bone Bed quarry stop on the way back.
  5. 11:30 am — Discovery Center on the east side (synthesis stop — Western Interior Seaway, K-Pg, Front Range uplift).
  6. 12:30 pm — Lunch in downtown Morrison (Morrison Inn or The Cow). Drive 5 min to Triceratops Trail stretch if time.
  7. 1:30 pm — Continue to Red Rocks (4 mi south) for the afternoon, OR back to Denver for DMNS.

Family roles:

  • Chris leads: logistics, ticketing, parking, hydration management on a first-day-in-Colorado high-altitude site.
  • Heather leads: the trackway interpretation walk (botany/keen-eye spotter — she'll see prints we'd miss).
  • Maxine drives: picks the dominant lens for the visit — paleo-biomechanics (run the Alexander equation), bone-wars history (read placards as primary sources), or structural geology (dip/strike + Laramide). Owns the field sketch.
  • Solo vs. both parents: both. It's a casual walk; the value is in three different sets of eyes catching different details.

Connections

Combines well with:

  • Red Rocks — 4 mi south, same Dakota Hogback, dramatically different rock unit exposure (the Pennsylvanian-Permian Fountain Formation, ~150 million years older than the Morrison). The hogback-walk-then-Fountain-walk is the classic Front Range geology day.
  • Denver Museum of Nature & Science — has the best regional vertebrate paleontology collections; the Morrison material she sees in situ at Dinosaur Ridge connects directly to specimens at DMNS.
  • Colorado Railroad Museum — 8 mi NW in Golden, an easy after-lunch detour.
  • Garden of the Gods — same Fountain Formation as Red Rocks but down in Colorado Springs; chains a Dinosaur Ridge → Red Rocks → Garden of the Gods Front Range geology arc across 2–3 days.
  • Florissant Fossil Beds — younger (Eocene, ~34 Ma) volcanically-preserved insects and plants; pair as a "Colorado paleontology, deep + recent" two-stop project.

Feeds into home projects / future adventures:

  • A trackway-biomechanics unit (compute speeds of every trackmaker on the Morrison wall, write up).
  • A "Bone Wars" research project using Yale Peabody's digitized Marsh correspondence as a primary source.
  • Future trip: Dinosaur National Monument (UT/CO border) — the original Carnegie Quarry wall with 1,500+ in situ Morrison bones. Logical sequel to Dinosaur Ridge.
  • A Front Range structural-geology project building on the Laramide uplift threads from this site + Red Rocks + Garden of the Gods.
  • Cross-reference with Dinosaur Valley in TX — Texas's Cretaceous (Glen Rose Fm) trackway site, ~6 million years older than the Dakota tracks here; build a comparative trackway notebook.

Open questions / still to research (Chris's side)

  • Verify exact 2026 bus-tour schedule and book online for our specific date.
  • Decide single-day pairing: Red Rocks (4 mi south, geology continuity) vs. DMNS (Denver, paleo continuity).
  • Pre-order Friends of Dinosaur Ridge self-guided trail map (or download the current PDF; check it's the 2024+ revision).
  • Confirm Triceratops Trail status — it's a separate site and access depends on the Rooney Ranch concession's hours.
  • Confirm road-walking access for our date (the road is closed to cars weekends + holidays + summer weekdays, which is good for walking; on open-to-traffic weekdays parking is at trackway pullouts).
  • Set altitude-acclimation plan: if this is Day 1 from Austin sea level, the ~6,000 ft elevation here is mild but real. Confirm Maxine's hydration baseline before any higher-elevation stop later in the trip.
  • Decide whether to commission a private docent hike (~$200 for 1.5 hr) — likely worth it if she's deep into the geology angle.