LAND CONSERVANCY #GEOLOGY HIKE: PHELPS CREEK HEMLOCK GORGE

from left to right:  Geologists Pat Biliter and Paul Ruez, WRLC volunteer Jim Sarosy and Brett Rodstrom, WRLC Northeastern Field Director study the eroded bedrock of Hemlock Gorge at Camp Whitewood.  WRLC Grand River Watershed Coordinator George Warnock is on the opposite bank, collecting trash

 Saturday    August 11, 2012    Phelps Creek Hemlock Gorge Hike  9 AM to Noon at Camp Whitewood, Windsor, Ohio   Presented by the Northeast Chapter of the Land Conservancy  

Free event, donations appreciated

A group of us took a preview tour of the Hemlock Gorge last week to study the effects of glacial activity, weathering and erosion in the area.

Here are a few of the many interesting formations we found as we trudged through Phelps Creek, a major tributary of the State Scenic and Wild River, the Grand River:

A seriously eroded sedimentary boulder

Tip of igneous boulder metamorphosed by heat and pressure into Gneiss

Shale cast AND matching mold of stream ripples found by George

Potholes in stream bed caused by abrasive swirling of gravel-sized and larger-sized rocks

Fossilized stream ripples along gorge wall

Stream ripples in upper right corner flowed diagonally toward lower left corner; stream ripples in lower left corner flowed diagonally to right lower corner.

Brett calls our attention to a rare Mountain Maple, which Paul told us is mentioned in John Denver’s “West Virginia.”

   Hikers studying fascinating formations in the opposite gorge wall

Pat Biliter’s photo of a ball and pillow formation (second horizontal formation from the top) and his explanation below:

“The ball and pillow structure is a type of soft sediment deformation that occurs in sandstone deposited over a silty surface, and less commonly, in limestones deposited over muddy sediments.

“The structures have been reproduced in laboratory flumes by jolting soft sediments under a flowing water current.  In other words, these things form in response to a big shock or impact, such as a massive earthquake.

“If you think about it, that’s not a far-fetched hypothesis.  Modern-day earthquakes in Ohio are puny little things, but we’re talking 360 million years ago when the Appalachians were growing into a Himalayan-size mountain chain.

“I’ll bet that Ohio would have been subject to some massive shaking, similar to the earthquakes that occur in Turkey and Southwest Asia today.”

Dr Joe Hannibal, CMNH’s Curator and Head of Invertebrate Paleontology, says that the Berea Formation at Phelps Creek is full of “weird stuff.”

Please join us August 11th to discover the wonderfulness of the weird and to hear Pat Biliter’s understandable enunciation of how, why and when the “weird stuff” got here.

The stream bed is rugged to walk through.  Pat Biliter recommends light tennis shoes rather than heavier hiking shoes and a hiking stick to navigate algae-slick boulders and Devonian Berea Sandstone.

For reservations and directions, please RSVP to Kim Bihler at

 kbihler@wrlandconservancy.org  or 440 729-9621

Photos © Carole Clement

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