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News Feature

State of Maine
Originally published in Castine Patriot, June 26, 2014
Glacial striations

Glacial Striations in Maine

One view of the striations on a rock formation in Maine.

Photo by Peter Cooperdock Order prints of selected PBP photos.

by Peter Cooperdock

A fine sitting spot overlooks Wadsworth Cove a short walk from the town beach. On private property at the high tide line, a bedrock extrusion forms a relatively level place to sun oneself or sit and watch the seagulls play and the osprey call. Sometimes, these places are called ledge, but a geologist pointed out to me that ledge is the vertical face of bedrock. Everything else is simply bedrock.

This particular piece of bedrock has likely been witness to many human occurrences. Numerous events and conflicts which have happened in the location that has become Castine have occurred near this rock. Now, there are more peaceful times in this location. Walkers from the beach extend down the cove at low tide to enjoy the beauty of this area and rest a moment or more here.

On this rock is evidence of more dramatic days than anything people have done. Long parallel grooves are evident on the surface. They point from the northwest to the southeast. These are striations left by the grinding of rocks at the bottom of the continental glacier that passed through this way in the last 20,000 years or so. These marks confirm this is bedrock, as a rock would have moved.

Glacial striation, as these are called, can be found in many other places as well. The orientation reveals the direction the glacier was taking as it passed. The depth of the striations reveal the hardness of the bedrock itself, as well as the hardness of the material which cut the grooves. They take us a little out of ourselves and into places and conditions that once were.

Ships were scuttled near here during the Penobscot Expedition. Cannon roared from the forts on the shore. Conflict raged over the centuries that mark the past of this strategic location. This piece of bedrock lay undeterred. Now it shines as the sun heats its surface and makes a beach goer take a moment out of their day to relax and reflect.

Striations on a Maine rock formation

Another view of striations on a Maine rock formation—these from right to left—show marks created as a glacier passed over the rock.

Photo by Peter Cooperdock
Glacial Striations in Maine

One view of the striations on a rock formation in Maine.

Photo by Peter Cooperdock