Investigating sedimentary rock deposition and weathering in Mawikwe Bay Sea Caves
Summary
Students will hike to the Mawikwe Bay Sea Caves along the frozen shoreline of Lake Superior in order to investigate the sedimentary rock deposition and weathering of the sandstone cliffs. Students will measure take measurements, photographs, and produce sketches of various sections of the sea caves. Students will share information and create a narrative of how the sea caves were formed and how they continue to change.
Learning Goals
Context for Use
The Mawikwe Bay Sea Caves are found along the southern shoreline of Lake Superior in northern Wisconsin, east of Cornucopia, and west of Bayfield. The caves are accessible only by water in the non-ice seasons, and by ice during the winter. The caves are made of sandstone that was deposited by braided rivers which have then been highly weathered by Lake Superior wave action.
Description and Teaching Materials
Students will hike along the frozen shoreline of Lake Superior to investigate the Mawike Bay Sea Caves, part of the Apostle Islands National Lakeshore in northern Wisconsin.
A. Students will be allowed some time to explore the sea caves prior to beginning the activities.
B. Students should sketch a section of the cliffs, specifically indicating boundaries between layers and areas of greater or less resistance to weathering.
C.Students will work in small groups to complete an inquiry investigation, based on the "Teachers 12-Step Program for Inquiry-based Field Investigations."
1. Working in small groups, make observations
2. Record observations
3. Large group discussion and questions
4. Teacher-guided question formation
5. Students select a question
6. Students design a study
7. Collect data
8. Modify procedures
9. Analyze results
10. Share data
11.Generate hypotheses
12. Present results
Presentation of results can be made informally at the field site, and then posters created and presented more formally in the classroom.
During the question selection step, the teacher should guide some groups to follow individual layers of sandstone along the cliff face. Also, some groups should be encouraged to investigate the various weathering rates of different layers of sandstone.
Teaching Notes and Tips
A backpack containing measuring equipment should be brought to the site.
Assessment
Standards
8.III.A.2 weathering and sediment deposition
8.III.A.3 rock cycle
8.III.A.5 constructive and destructive processes
Wisconsin Model Academic Standards:
C.8.7 explain conclusions
E.8.3 forces changing earth
E.8.5 geological history