I have been traveling U.S. Highway 12 between Baraboo and Madison, Wisconsin, my whole life — literally. I was born at University Hospitals in Madison and had my first ride home to Baraboo when I was 2 weeks old. As a child, we came to Madison in my earliest years to appointments with the pediatrician, the eye clinic, and the orthodontist. Every year, before school started in the fall, we came to shop for new school clothes in the many stores around the Capitol Square. Once in a while we drove to Madison to attend concerts. (I remember on one occasion, probably when I was 8 or 10 years old, my sister and I came with our parents to hear the world-renowned pianist Artur Rubinstein perform in the Memorial Union Theater. Eleanor and I “split” one ticket — she attended the first half of the program and I attended after the intermission. At the time, I worried some about whether or not we were “breaking the law”!)
And so I came to know the 42 miles between Baraboo and Madison well — the contours of the land, the small towns, the farms, the rivers, the bridges, the special points of interest. Now, in my adult years, I realize that this highway offers much more than a way to get from Baraboo to Madison. The highway is, in fact, a living historical record of places, events and changes that have been an integral part of the region and of my life across these years. The countryside along U.S. Highway 12 offers at least four layers of historical significance to me:
- Deep geological time including some of the earth’s oldest exposed rock formations, known to and studied by geologists from around the globe;
- Native American history including the tensions that came with European settlers;
- The conversion during World War II of some of the most fertile, privately owned farmland in the state into the U.S.Badger Army Ammunition Works during WWII. At the time, this plant was one of the largest in the country, with operations that continued during the Korean War and, even to some extent, the Vietnam War; and
- My own personal memories of places and events associated with Highway 12.
I will describe the first of these — geological time — in this posting. The other three will come in the next blog.
DEEP GEOLOGICAL TIME
How can I capture the essence of the Baraboo Hills in a few paragraphs? The Hills comprise about 200 square miles of land, with north, south, east and west ranges forming a sort of oval or elliptical shape. The range is clearly visible in satellite imagery. The town of Baraboo is located within the valley that lies between the high ranges.
The Baraboo range has been referred to as a geologist’s “mecca”, one of the world’s “remaining outstanding ecosystems,” and the “remnant of an ancient quartzite mountain range.” Ancient — as in really, really old. U.S.Highway 12 makes its way south through the Baraboo Hills as it heads from Baraboo to Madison.
One of the first obvious signs of the Hills is a rather sharp curve in the highway, just four miles south of Baraboo, a curve that cuts through an enormous stone outcropping of quartzite called “Point of Rocks.” This prominent outcropping of quartzite is very important to geologists because it has the best exposure known of sedimentary features — features that help tell the tale of the earth’s development over an estimated 2,800 million years. The Baraboo rocks date from an estimated 1,650 million years ago. The many features of the outcropping were studied by a University of Wisconsin geology professor in the late 19th century and were used to describe the various phases and layers of the planet’s topographical formation. Features such as cross bedding, soft-sediment deformation, stratification, and ripple marks were observed and identified at that time by Professor Van Hise, and his methods and findings laid the groundwork for structural geology theory and practice today.
Can you see the “syncline” of the quartzite? The rock is inclined 25 degrees to the north, i.e. the layered rocks are downbending toward the north. Exactly what causes such deformations is unclear.
After completing the sharp curve around the Point of Rocks, the highway immediately begins to ascend the east range of the Baraboo Hills, traveling up and over and then down, down onto an outwash plain. The outwash plain consists of deposits left behind by the rivers that drained the last Wisconsin glacier some 90,000 years ago. Off to the east can be seen the low ridge of the Johnstown Moraine,also known as the terminal moraine, an accumulation of sediment along the margins of the Green Bay Lobe of last glacier. Off to the west can be seen the hills of the Driftless Area, a term used to identify areas in the Midwestern United States that were not covered by the Ice Age glaciers. The highway, in effect, crosses over the outwash plain between these two geological features — the Johnstown Moraine to the east and the Driftless Area to the west.
In recent years, now with at least rudimentary understandings of the geology of the Baraboo Hills, I see the Hills and ridges and plains and quartzite along the highway with very different eyes. The deep geological time exposed in these rocks feels like a visible sign of creation. And my “respect” for all rocks in the world has increased a thousand fold.
Dott, R.H. Jr, & Attig, J.W.. (2004). Roadside Geology of Wisconsin. Mountain Press Publishing Company: Missoula, Montana.
Kruse, H. (n.d.). Natural Areas in the Baraboo Hills. Published in cooperation with Goblin Fern Press, http://www.goblinfernpress.com
Lange, K.I. (2014). Song of Place: A Natural History of the Baraboo Hills. Ballindalloch Press: Baraboo, WI.
Google: Devil’s Lake State Park Baraboo Hills Wisconsin for spectacular views of the quartzite rocks on the bluffs around the lake.
(To Be Continued)