ISLANDS AND TIME: AN INQUIRY-BASED EARTH HISTORY ASSIGNMENT

The second year Earth History course at McMaster University includes an inquiry-based assignment aimed at enhancing students' understanding of geological time and stratigraphy through creation of an imaginary island and its geologic history. Earth History is a compulsory core course taken by all B.Sc. Honours Earth and Environmental Sciences students. The ‘Create an Island' assignment is the final assignment in the 13-week course and serves as a ‘capstone' experience for the students, allowing them to explore the relationships between geologic time, rock types, fossil types and paleoenvironmental conditions. Students work in teams of 4 or 5 to complete the assignment during their 2- hour weekly lab period over a period of four weeks.

The assignment: Each group creates an imaginary island and describe its geological history in an oral and a poster presentation to the class. The island must contain a specified number of igneous, metamorphic and sedimentary rock types, fossil types and at least two unconformities. Radiometric ages must also be provided for two geologic horizons. Students create a geologic time line describing the formation of their island, as well as a geologic map, a cross section and a stratigraphic column for their final presentation and poster. Students are encouraged to be creative in their presentations and many groups produce 3-D models of their island for illustration.

What students learn! Students do not find this assignment easy! It requires them to really understand the temporal aspects of geology as they must consider rates of geological processes, assign fossils to appropriate stratigraphic positions and have a working knowledge of both absolute and relative age dating. They must also create a geologic history that is consistent with known paleoenvironmental changes recorded over geologic time. The process of creating a geologic timeline for their island allows students to fully integrate their understanding of geologic time with rock types, fossils, geologic structures, and paleoenvironmental conditions. Students also develop skills in the areas of information retrieval, critical thinking, problem solving, team work, visual and oral presentation.