Otter Point — Reading the Glacier in the Granite
Listen at the stop, then read the transcript and follow the sources behind the story.
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Transcript
At Otter Point the dramatic object is the ocean, but the shape of the land owes as much to ice. Acadia’s mountains and valleys were repeatedly overridden by continental glaciers. Ice does not merely cover a landscape; rock fragments frozen into its base can grind, polish and pluck the bedrock beneath.
The result around Mount Desert Island is a terrain of rounded summits, U-shaped valleys and exposed granite surfaces. Later, rising sea level flooded low areas and created the complicated meeting of mountain and coast that defines Acadia today.
Look at the granite as structure rather than colour. Fractures break it into blocks. Waves exploit those weaknesses along the shore, while freezing water can widen cracks inland. The coast is therefore being dismantled along lines that were already present in the rock.
This is also a reminder that the postcard version of Acadia is temporary. The cliffs appear massive because human lives are short. Over geological time, the same processes that made the headland scenic are taking it apart.