Think-Aloud Modeling of Geologic Reasoning in the Field
In a field class, the instructor shares all thoughts with students as the group examines outcrops, roadcuts, or geologic traverses. Such thoughts include observations, possible interpretations, what additional information is needed, potential strategies for approaching problems that arise, doubts about what is knowable and what is not, and anything else that comes to the instructors mind.
Methods of GeoscienceThis activity helps develop geologic reasoning skills by helping students to the following:
(1) distinguish observations from interpretations,
(2) make predictions and brainstorm what data are needed to evaluate a prediction,
(3) consider different strategies for approaching a field area, and
(4) appreciate the impact of incomplete data.
Context for Use
Description and Teaching Materials
(1) kinds of background knowledge that are being accessed, even at the most basic level (e.g., hornblende is more common in andesite than basalt);In other words, the instructor is explicitly modeling the entire thought process for the students, not a pre-edited, tidy version. If we want students to think like a field geologist, we should show them exactly what we mean, dead-ends and all.
(2) what key aspects are being focused on and which ones are being downplayed (e.g., this is layering but that is rock varnish);
(3) specific criteria that are being used (e.g., is this metamorphic rock homogeneous or heterogeneous);
(4) strategies that are being employed or at least considered (e.g., I should proceed from the least deformed part of the outcrop to the most deformed part);
(5) possible interpretations, even those that are quickly discarded (most instructors do not share these with students);
(6) ideas about aspects of the geologic history that arise from the observations and interpretations, including how these fit or do not fit into the regional setting; and
(7) any tangential thoughts to which the outcrop leads.
Teaching Notes and Tips
References and Resources
Johnson, J.K., and Reynolds, S.J., 2005, Concept sketches – Using student- and instructor-generated annotated sketches for learning, teaching, and assessment in geology courses: Journal of Geoscience Education, v. 53, p. 85-95.
Tewksbury, B.J., Reynolds, S.J., and Johnson, J.K., 2004, Using student-generated concept sketches for learning, teaching, and assessment in structural geology courses, Geological Society of America Abstracts with Programs, v. 36, no. 5, p. 347. (see also various documents on the SERC website)
Lucas J. Reusser, Lee B. Corbett, and Paul R. Bierman, 2012, Incorporating Concept Sketching Into Teaching Undergraduate Geomorphology. Journal of Geoscience Education: February 2012, Vol. 60, No. 1, pp. 3-9.