Page 383 - Laboratory Manual in Physical Geology

A CTIVIT Y 13.3 Continental Glaciation of North America

Name: ______________________________________ Course/ection: ______________________ Date: ___________

A. Refer to FIGURE 13.12 , part of the Peterborough, Ontario, quadrangle, for the following questions. This area lies north of

Lake Ontario.

1. Study the size and shape of the short, oblong rounded hills. Fieldwork has revealed that they are made of till. What type of
feature are they and how did they form?

2. Find the long narrow hill labeled A . It is marked by a symbol made of a long line of tiny pairs of brown dots. What would
you call this linear feature, and how do you think it formed?

3. Towards what direction did the glacial ice flow here, and how can you tell?

B. The most recent glaciation of Earth is called the Wisconsinan glaciation. It reached its maximum development about 18,000

years ago, when a “ Laurentide Ice Sheet ” covered central and eastern Canada, the Great Lakes Region, and the northeastern
United States. It ended by about 11,700 years ago, at the start of the Holocene Epoch. Refer to FIGURE 13.13 , a portion of

the Whitewater, Wisconsin, quadrangle.

1. List the features of glaciated regions from FIGURES 13.8 and 13.9 that are present in this region.

2. Describe in what direction the ice flowed over this region. Cite evidence for your inference.

3. What kinds of lakes are present in this region, and how did they form? (Refer to FIGURE 13.7 .)

4. In the southeastern corner of the map, the northwest-trending forested area is probably what kind of feature?

5. Note the swampy and marshy area running from the west-central edge of the map to the northeastern corner. Describe the

probable origin of this feature (more than one answer is possible).

C. REFLECT & DISCUSS How are the glaciated areas of FIGURES 13.12 and 13.13 different from areas affected by mountain

glaciation and how are they they same?

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