The Geological Column: Campus rocks

Breanna Skeets

Natural disasters like the Haiti earthquake and the Japanese earthquake and tsunami have made people more aware of the geologic forces that shape the planet. No doubt some of us from the West Coast — and perhaps other parts of the country — have been part of earthquake drills. Wisconsin, however, seems remote from any of this geologic action. Yet geology influences our lives in many very subtle ways, and for the geologists on campus, there’s even a geologic story in our buildings!

Let me take you on a tour of campus where you can see diverse geology. The cream-colored rock that you see on the outside of the Warch Campus Center is called dolostone. This rock type is in many parts of Wisconsin, particularly along the Niagaran Escarpment, which includes High Cliff State Park — familiar to many intro geology students. This dolostone is a sedimentary carbonate rock formed in warm, shallow seas hundreds of millions of years ago when Wisconsin was in the tropics. Dolostone is probably the most common rock on campus, featured not only at the WCC, but also on the exteriors of Youngchild Hall, Main Hall, Hiett Hall and the quad buildings.

Now, if you walk inside of Warch you may be distracted by the general splendor of the spring sunlight, the smell of the café or just rushing down to Andrew Commons to grab some food. However, some of us will take the time to walk inside of Warch and look down. The tiles on the floor of the campus center are made of phyllite. This is a metamorphosed version of shale — mudstone — which initially formed from tiny clay particles but is transformed through high pressure/temperature conditions during mountain building into much tougher rock. We’re not sure where this particular phyllite comes from, but it represents the roots of an ancient mountain belt!

Another rock with a dramatic history forms the floor of Steitz Hall atrium: gabbro. Gabbro is a dark, coarse-grained, intrusive igneous rock. This rock formed as a large magmatic mass that cooled slowly in the earth’s crust. The size of the grains reflects the long cooling time of the rock — it takes time for crystals to grow that big.

Once you get in the habit of looking at the floor and walking up to walls, you’ll discover that there are other beautiful rocks around campus, like the granite outside the landing of Memorial Hall and the fossiliferous limestone in the bathrooms inside that building. Then you will have to admit that you too are a rock geek!