Mapping Glacial Erratics with GPS and GIS

Katherine McCarville, Upper Iowa University


Students create a map of glacial erratics (in Northeast Iowa, although you could do this wherever you have glacial deposits). The activity uses local geology, and could be applied in areas where bedrock is not accessible.


Type and level of course
This is a new activity which I plan to use in an introductory geology class in Fall 2010, and potentially continue into an upper-division GIS/remote sensing course in Spring 2011, and ultimately an upper-division geomorphology class.

Geoscience background assumed in this assignment
No previous geoscience background will be required, but students will develop the ability to identify rocks found as glacial erratics in our area.

GIS/remote sensing skills/background assumed in this assignment
No previous GIS background will be required, but students in the upper division GPS class will develop the ability to acquire GPS point data and populate attribute tables. They may also use LIDAR data for terrain analysis.

Software required for this assignment/activity:
ArcView, any version. This activity could be done on topographic maps, if the glacial features are of appropriate scale.

Time required for students to complete the assignment:
If you have a boulder train handy, it could be just a few hours. If the activity is done as true inquiry-based learning, it would depend upon the size of the area to be mapped.


GIS/remote sensing techniques students learn in this assignment
Students will learn to acquire point data with GPS units. They will identify rock type and other characteristics of glacial erratics. Ultimately, this data will be overlayed on LIDAR imagery and analyzed to identify glacial features such as moraines and outwash channels.

Other content/concepts goals for this activity
Students will identify the composition and rock type of each erratic, and develop a classification system including angularity/rounding, size, and weathering.

Higher order thinking skills goals for this activity
In the introductory geology class, the primary goal will be to develop students' understanding of landscape change through time, weathering, erosion, and glacial processes.

In the upper-division GIS/remote sensing and geomorphology classes, the primary goal will be use of real imagery and GIS data in an inquiry-based study.

Description of the activity/assignment

This study is planned for Academic Year 2010-2011. Our task is to understand the glacial deposits of our area, which have not been mapped recently or in much detail. It will begin with students in an introductory geology class learning to identify rocks found as glacial erratics in our area. Their data will be plotted and shown on the background of LIDAR data for the area. Later classes in GIS/remote sensing and geomorphology will add data and refine the analysis.

Determining whether students have met the goals

Intro geology students will be able to demonstrate their ability to describe and identify a variety of rocks. They will be able to describe and identify rocks during quizzes and exams.

Upper-division students in GIS/remote sensing will create maps and reports describing the distribution of glacial erratics in the study area. They may use LIDAR data in their analysis.

Upper-division students in geomorphology will analyze the distribution of rock types, size, weathering, and rounding to identify glacial landforms including moraines and outwash channels.
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