November 25, 2010

A Thanksgiving Rock: Granodiorite

Posted by Evelyn Mervine

Plymouth Rock, image taken from Wikipedia Commons.

Happy Thanksgiving, everyone!

In honor of Turkey Day, I want to share with you an article by John McPhee, one of my all-time favorite writers. McPhee wrote an article about Plymouth Rock that can be read here: Travels of the Rock.

Like the Pilgrims, Plymouth Rock- which marks the Pilgrims’ traditional, almost mythical landing place– was a traveler. This rock is a glacial erratic, a piece of bedrock that was scraped up by a glacier and transported miles and miles from its original location. However, Pilgrim Rock didn’t travel quite as far as the Pilgrims themselves… unless you count earlier Plate Tectonic wanderings. Most likely, Pilgrim Rock is a piece of Dedham granodiorite from Eastern Massachusetts and came from no further than Concord or Lexington, according to the McPhee article. However, whatever its origin, I can think of no worthier rock to commemorate the Pilgrims’ voyage than a glacial erratic.