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Calvin News

Junior Researches Glacial Geology

Tue, Sep 18, 2007
Myrna Anderson

A Calvin junior was one of a team of students from several colleges who spent the summer researching the glacial geology of Minnesota and Brazil, a project funded by a National Science Foundation (NSF) grant.
Calvin geology major Laurie Koning, 21, joined geologist Jim Cotter from the University of Minnesota, Morris (UMM) and students from UMM; Gustavus Adolphus College; the University of Minnesota, Duluth; St. Cloud State University; the University of Wisconsin, River Falls; and the Universidade de Sao Paulo, Brazil in a project supported through $165, 000 from the NSF Research Experiences for Undergraduates program.聽
The team studied the deposits left behind by retreating glaciers in both the Midwest state and the South American country.
Because the glaciers came through the United States less than 20,000 years ago and through Brazil 300 million years ago, the deposits they left behind look different, Koning said.
鈥淯p here in the United States," she said, "you have the gravels and the sands. In Brazil you see a lot of weathering of the rock.鈥澛
The faculty student team used the observations from the younger deposits to interpret the older deposits, which are poorly preserved.聽
鈥淚n certain regions, such as Minnesota, the most recent geologic activity is glaciers. Anything else is eroding. Since the glacial time, there鈥檚 not been any more buildup of sands and soils,鈥 Koning said. 鈥淚n Minnesota, we would visit gravel pits. That鈥檚 a key place for glacial geologists to look. In the gravel pit you get a stratigraphic section, where you can see different deposits all on top of each other.鈥澛
While in Minnesota, each team member also carried out an individual research project. Koning studied the bedrock of the Glacial River Warren (an area where a river once existed) in the Big Stone National Wildlife Refuge. She was trying to settle the claims of competing geologists, some of whom claim that the river was caused by a catastrophic flood and some of whom claim that it was created by natural weathering.聽
鈥淚t turned out that there was not enough evidence to show that water had flown through there with enough capacity and speed to be a catastrophic flood,鈥 she concluded.
In Brazil the team assisted in a larger mapping project of one region carried out by a professor from the Universidade de Sao Paulo.聽
鈥淭here we had topographic maps, and we went around the pastures in this farming country and mapped where we found the rocks,鈥 Koning said. 鈥淲e were looking at the grooves on the surface. It was kind of a hunt to find grooves that were caused by the glacier.鈥
Her experience of Brazilian culture was somewhat atypical, she said because the team stayed in the Mennonite community of Witmarsum, founded by German-Swiss settlers.
鈥淚n that town, they spoke German and Portuguese. That鈥檚 nice for me because I speak German. I felt a little lost when we went to a small town one day, and they were all speaking Portuguese,鈥 said Koning, who studied in Austria while in high school and worked in an amusement park in Germany two summers ago.聽
Koning also celebrated her birthday in Witmarsum.聽
鈥淚n the southern hemisphere, it was winter. I鈥檇 never had a winter birthday. It was misty, rainy, cold,鈥 she said. 鈥淏ut we stayed at a bed and breakfast, and I had amazing cake for dinner.鈥
The team worked well together, and Koning said the project was a good research experience: 鈥淚t was great for learning how geologic field research is done.鈥