Robinson Bluff

Unearthing Missouri’s Geology

Meet Erica Doerr, the geologist and rock climber who unearthed the geologic history of Robinson Bluff.


Erica DoerrVertical Voyages tree and rock climbing assistant Erica Doerr unearthed the geologic makings of Robinson Bluff. The popular Missouri climbing destination is located one hour and 500 million years from St. Louis. A geologist by training, Erica moved back to the Midwest from New Mexico in 2021. There she worked for the Bureau of Geology and Mineral Resources.


Her passion for place-based science led her to dig deep into the makings of Robinson Bluff with its towering dolomite bluffs and pockets of sparkling mineral blossom deposits (aka quartz). While the rock’s multi-million year makeup may be the last thing on a climber’s mind, this fascinating story shows how the crag went from sea floor to spectacular spires.


Climbers are geologists, too


Erica says climbers are geologists who use different vocabulary to make similar observations. In fact, she encourages climbers to pay closer attention to the rock formations that make up our favorite climbs. Next time you’re at Robinson Bluff, here are four ways to be a climbing geologist:


      1. Enjoy the distinct color palettes at Picasso Wall. These colors were formed by the oxidation of various iron and manganese minerals that naturally paint the rock surface.
      2. Explore prime examples of honeycomb weathering. The formations, called tafoni, make great finger holds on the bouldering area known as The Den.
      3. Look for weathered druse quartz, chert or igneous rock. Cool off in the Big River after a summer climb and look for treasures transported from the St. Francois Mountains.
      4. Pay attention to the parking lot. As you wrap up the day, look down at the gravel that sparkles with chalcopyrite, pyrite, hematite, druse quartz, sphalerite and barite minerals.


Science is everywhere! 


“My passion is to connect people of all cross-sections of life to place-based science,” states Erica. “Whether it’s in the classroom, on the river, in a tree, or on the rock outcrop.”


In addition to Vertical Voyages, Erica is a STEM instructor for TRiO Upward Bound at SIUE where she connects high school students to careers in science. Fall 2022, she will start a new role as an Environmental Educator at the National Great Rivers Research and Education Center in East Alton.


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