🪨💧🌬️🔦
🌍 EarthCache So Easy, a Caveman Can Do It!
Ugg say: “Rock soft? No. Water sneaky. Make cave.”
Ugg himself approve this message.
Location: Stark Caverns, 125 Cave Dr, Eldon, MO 65026
Posted Coordinates: N 38° 17.073 W 092° 35.449 (≈ 38.28397, −92.59165)
Difficulty: 1.5 • Terrain: 1.5 • Size: EarthCache
Permission: Given by General Manager Matt Naughton ✅
💀 Ugg’s Rock Story (a.k.a. Background)
Hidden beneath the rolling Ozark hills lies one of Missouri’s most distinctive geologic landscapes—the
karst terrain. The Ozarks are famous for their labyrinth of caves, springs, sinkholes, and losing
streams, all carved through Mississippian-age limestone (including the Burlington–Keokuk units)
that formed roughly 330 million years ago when this region was covered by a warm, shallow tropical sea.
Over time, layers of lime mud, shell fragments, and corals accumulated on the seafloor.
As sediment piled up, compaction and cementation (lithification) turned these
carbonate sediments into solid limestone beds. Long after the seas retreated, slightly acidic rainwater—formed when
CO₂ dissolves into water to make carbonic acid—percolated downward through soil and
along fractures, dissolving calcite (CaCO₃) and gradually enlarging microscopic pathways into
conduits, then passages, and ultimately caves.
Stark Caverns sits within this same limestone sequence, making it a window into the Ozark aquifer
system. Water still moves beneath your feet today, flowing through hidden conduits toward the Osage River basin.
Each heavy rain continues the slow chemical ballet of dissolution, widening fractures by minute amounts each year.
At the entrance to Stark Caverns, you’re standing at a fragile boundary—the karst portal—where the
surface environment (variable temperature, vegetation, and weather) meets the subsurface environment (stable
temperature, darkness, and unique chemistry). This interface is where we can observe how ancient seas, modern
chemistry, and physical weathering (freeze–thaw, root wedging, runoff) work together to shape the gateway you see.
🧭 How to Find (Ugg Simple)
- Park near the visitor center/public area and walk to the posted coordinates.
- No cave entry required or allowed for this EarthCache. All tasks are outside.
- Stay in public/allowed areas; follow signs and staff directions.
📚 What Ugg Learn (Educational Objective)
- How karst topography forms in soluble rock like limestone.
- Why a cave entrance is a portal linking surface water and the underground system.
- How to spot active weathering right at the entrance.
Ugg’s Karst Legend:
💧 + CO₂ → carbonic acid (weak) → dissolves calcite (CaCO₃)
🪨 Limestone shows beds/layers, joints, fractures
🌬️ Freeze–thaw, roots, runoff = active shaping now
🚪 Entrance shape = clues to erosion & enlargement
✅ Required Logging Tasks (Prove Ugg You Learn)
- Layer Look: Describe the rock at/around the entrance. Are beds horizontal, tilted, or irregular?
Note layering, color, and texture (smooth, pitted, fractured).
- Rain to Acid: Explain how ordinary rain becomes acidic enough to dissolve limestone. Which gas
dissolves in water, and what is the weak acid called?
- Portal Profile: Estimate the entrance size and overall shape (arched, rounded, jagged). Based on
that shape, what process(es) likely formed or enlarged it?
- Still Changing: Identify one modern process acting here today (e.g., rainfall/runoff,
freeze–thaw, root wedging). Describe the evidence you see on site.
- From Sea to Stone: In your own words, connect the story: (a) what settled on the ancient
sea floor, (b) how it became rock, and (c) how that rock turned into today’s karst/cave landscape.
📸 Optional (Show Tribe Your Find)
- Photo of you/your GPS near a sign or obvious karst feature (faces optional; follow site rules).
- Share the most surprising thing you learned about karst at Stark Caverns.
⚠️ Access & Safety (Ugg Careful)
- Outside only. Do not enter the cave for this EarthCache.
- Watch footing on rock and edges, especially after rain; surfaces can be slick.
- Leave No Trace: do not disturb rocks, plants, wildlife, or formations.
- Obey signage and staff; remain in publicly accessible areas.
📌 Notes & Acknowledgements
- All observations are made at the entrance/grounds—no tour needed.
- If you choose to take a tour, follow staff guidance (tour not required to log).
- Thanks to Stark Caverns for support and public education.
- No fees required for parking, visitor center or hiking the trails
- Permission: Granted by General Manager Matt Naughton.
🪨💧🌬️🔦
Part of the Caveman Cache Series
Ugg approve science. Science good.
Reviewer note: All tasks are on-site observations at the public entrance/grounds; no cave entry is necessary or encouraged.