The following couple of locations north and east of Bascom Hill provide you with an opportunity to make some observations of rocks and minerals nearly in the wild. You do not have the background to learn everything about these rocks. Neither does your TA or professor. However we all can make observations and try to prioritize and utilize those observations to learn more about a particular rock or situation. It is in this spirit that we ask you to spend the next 50 minutes on this mini-trip. I hope that many of you will continue this exercise in 1-2 weeks on the Saturday trip to the Baraboo area.
[1] Start by the statue of Lincoln on Bascom Hill. Describe the rock making up the pedestal for the statue and the surrounding benches. Is this an intrusive or an extrusive igneous rock? Why?
[2] Proceed north across Observatory Drive and examine the small boulders that line the edge of the road. What variations in texture, color, or mineralogy can you identify? Why are these boulders here?
[3] Note the differential weathering on the different alumni monument stones in the grassy area adjacent to the boulders. What lessons about relative and absolute time can we learn by examining these dedications? List some features in these monuments that you could use to estimate their relative/absolute ages. How accurate do you think your age estimations might be?
[4] Walk out to the Lake Mendota overlook in Muir Park. Examine the large rock (shaped like a Viking ship?) how would you describe the texture and fabric in the bulk of the rock? What about the light colored bands/layers/veins (which are they)? Which parts of this rock are oldest? Youngest?
[5] Turn your attention out to the lake can you see the Cambrian (Jordan) sandstone cliffs across the lake at Maple Bluff? What underlies your feet and Bascom Hill more sandstone?
Holes drilled into Bascom Hill have penetrated lake silts 12 feet above the present level of Lake Mendota, indicating a substantially deeper lake in the past. What are the geological implications of another 10-12 feet of water in Lake Mendota? We will return to this question later in the course (hint: when we talk about glaciation).
[6] Make your way down to the rock wall that lies just west of the ground floor of Helen C. White Library. Spread out along this wall and try to find 5 substantially different rock types and/or features. Consider mineralogy, weathering, color, texture, internal structure, style of breakage.
How would you go about communicating the locations of your fabulous geological finds on this wall to the next discussion group to visit How would you map this wall? - List things that you think would be important to include on your map. Sketch a sample map of a portion of the wall.
[7] Final stop compare the rock making up the rim around the fountain west of Memorial Library to the steps on the west side of the library. How do they differ? How do they compare to the base of the Lincoln statue? (Did you take good notes? Draw pictures? Wish you had?)