Friday, November 11, 2011

The drive to 7 Springs...and dancing for snow

Eight inches of snow fell at Seven Springs during the weekend before Halloween, while big, fat, wet flakes dropped in Pittsburgh. Even though we're moving back and forth between warm and cold this November, whenever the cold sticks around the air smells perfect right before sunrise and I can imagine the sound of boots crunching on packed white goodness during the walk over to the lifts. Soon I'll be making a regular drive between Pittsburgh and Seven Springs, and even though my my mind will be focused on getting on to the snow as quickly as possible, it's always fun to entertain myself during the drive by listening to some awesome playlists and gawking at the visible sedimentary layers in highway roadcuts.

First 2011 snowfall in Pittsburgh on Big Mama Jeep
Weekend trips to Springs involve a fairly regular routine, which involves waking up super early, putting on snow gear, loading stuff into the car, and stopping for a very large, highly-caffeinated hot beverage. With the playlists ready and loaded onto the iPod, and Big Mama Jeep full of gas, I hop onto I-376 from Squirrel Hill and catch the PA Turnpike near Monroeville, heading east towards the Donegal exit.

Ready to roll in Big Mama Jeep
Most of the drive cuts through the Allegheny Plateau, which is the big, flat expanse of mainly Pennsylvanian and Mississippian rocks that reaches across the western part of Pennsylvania (see the PA Geologic Map below). These rocks are kind of old (a few hundred million years) and are a mix of sandstones, shales, conglomerates, limestone...basically anything that deposited out of lakes and streams, and that was moved around by passing glaciers. Some of these layers also include coal (note the billboards that pepper the roadside along this drive, highlighting coal as one of our primary regional energy resources).

Geologic Map of PA, from the PA Geological Survey
If you look at layers in some of the roadcuts around Pittsburgh, they look generally flat. Hills in this area developed from streams and rivers cutting through the sedimentary layers (that were already deposited by older streams, rivers, glaciers, etc.) over the past 200 million years, and glaciers scrubbing rock in some places and depositing stuff in other areas. Moving east across the Allegheny Mountain and Allegheny Front sections along I-76, the layers are folded a in a series of synclines (think: distorted U-shaped layers) and anticlines (think: distorted rainbow-shaped layers) that trend northeast; these developed due to North America and Africa smacking into each other roughly 300 to 220 million years ago (the continents have since parted ways).

Map showing synclines and anticlines along I-76, scanned from Roadside Geology of Pennsylvania by Bradford B. Van Diver
There are some nice displays of the folds in exposed roadcuts between the New Stanton and Donegal exits on the Turnpike, and the I-76 path through these folds is shown on the map above. I recently ordered a quadrangle for the Donegal area, so more detail on Seven Springs-specific geology is coming soon. Since the weather has been warm for the past few days, Team Haleakala prepared this snow dance video for the Seven Springs contest this past weekend to help bring on the snow...enjoy!

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