The Long View: Half a Billion Years in the County



The view from State Street in Presque Isle

This August I spent a week in mythic Aroostook County.  Throughout my week there I navigated rolling hills and potato fields, marched to the top of Quaggy Jo in Aroostook State Park and summited Haystack Mountain in Mapleton. The county is a geological wonderland, but it wasn't until I crested that hill in Presque Isle that I recognized the magic of the place.



The view of Haystack Mountain from State Street in Presque Isle

Traveling down State Street into Presque Isle, you turn a corner, the road dips downward, and you look across the county at Haystack Mountain. That rock has been on Earth for half a billion years.  Once the neck of an ancient volcanic island, the Aleutian-like island gained girth as the North American ocean bottom slid under a second ocean plate. The lightest of the melted ocean rock floated to the surface forming the steep-sided stratovolcano that would one day become the western view from Presque Isle.

The view of Quaggy Jo from State Street in Presque Isle

If you're not completely transfixed by Haystack, your eyes may wander south as you pass Presque Isle's school farm. As if the beautiful farm were not a sufficient view, this vantage provides sight of another prominence - Quaggy Jo of Aroostook State Park. Compared to Haystack, Quaggy Jo is a young'n.  Formed 410 million years ago, it holds an esteemed place in Maine geology, along with Traveller Mountain and Mount Kineo, as the volcanic remnants of Maine's most intense collision. A microcontinent we call Avalonia was nearing the coast of Maine.  Its leading edge plunged beneath the North American coast. Avalonia would become our coast and the melted ocean would rise up through the ocean to become the aforementioned volcanoes and their granitic roots - some of the largest mountains in Maine.



The collisions weren't over yet. When the last of Avalonia's fore-ocean descended, the sub-continent continued forward. The colliding land masses were too light to sink into the Earth's mantle below, so the smashing crushed everything skyward.  Formerly flat ocean bottom became wrinkled like a discarded sock. In some places in the Appalachians the squished rock climbed higher than today's Himalayas. Here in the county, hundreds of millions of years later, all that's left are the rolling hills that I drove over.

At that turn, on that road, I could see into Maine's geologic past. I saw an ancient ocean lap the shores of Haystack Island. Quaggy Jo volcano erupted right in front of me. The very hill I stood on rippled upward as Avalonia invaded our shore. The chaos of a half a billion years, wrapped into a single panorama on a peaceful hill. 

Boone, Gary, William  Forbes, and Chunzeng  Wang. "Haystack Volcanic Geology and Geologic History." Go Aroostook Outdoors. N.p., n.d. Web. 10 Oct. 2014. <http://goaroostookoutdoors.com/sites/default/files/trails/maps/HaystackGeology.pdf>.



Caldwell, Dabney W.. Roadside geology of Maine. Missoula, Mont.: Mountain Press Pub. Co., 1998. Print.

Roy, David C.. "Geologic Map of the Caribou and Northern Presque Isle 15' Quadrangles, Maine." Maps, Publications and Online Data. Maine Geological Survey, n.d. Web. 10 Oct. 2014. <http://www.maine.gov/dacf/mgs/pubs/online/bedrock/87-2.pdf>.