Campus Landscaping By Constructing Mock Geologic Outcrops

Journal of Geoscience Education, Sep 2006 by Matty, David J

ABSTRACT

Student learning in the geosciences is enhanced by exposure to geology "in the field," where students put knowledge into practice to solve problems and make interpretations. Nonetheless, geography and cost may limit the ability of many institutions to provide adequate field experiences for their students, especially in large introductory courses. However, institutions may transform portions of their campuses into geological learning environments conducive to instruction at all levels by constructing mock outcrops. On our campus, we have constructed a variety of mock outcrops that range from simple groupings of lithologically distinct boulders to a complex campus geological area" encompassing a variety of igneous, sedimentary, and metamorphic rocks, various artificial unconformities, and simple to complex structural relationships. Students from all instructional levels utilize the contrived geology that we have constructed and results indicate enhanced student learning as an outcome. By learning from our experiences, including the successful and unsuccessful events that helped us develop our campus as an educational tool for the geosciences, others may be able to better develop their own campus in support of geoscience instruction.

INTRODUCTION

Outcrop-based field experiences, such as those often provided to geoscience majors, also have the potential to positively impact student learning across the curriculum by enhancing understanding of correlation and relative dating, by providing pathways to developing spatial visualization and other skills, and by increasing comprehension of lithologic characteristics and processes. These benefits and others have been discussed by a number of authors, including Spencer (1990), Karabinos, et al. (1995), Manner (1995), Kali, et al. (1997), and Orion, et al. (1997). A question faced by numerous geoscience departments remains: how does an institution in a geology-challenged area provide a variety of field experiences for all of its students?

The idea of using one's campus as an educational tool and of facilitating geoscience education via rock groupings and man-made or mock "outcrops" is not new. Dillon et al. (2000) constructed a labeled boulder garden and separate mapping area composed of labeled rock slabs and boulders representing the local bedrock stratigraphy of the region. Calderone et al., (2003) constructed an artificial structure" from colored gravels and larger, strategically placed samples, and incorporated two vertical "outcrops" to add an obvious third dimension to their design. Our construction, which we refer to as the Campus Geological Area (CGA), is similar to certain aspects of both the Dillon et al. and Calderone et al. designs, but also differs substantially in size and scope. Most notably, our CGA consists of a series of realistically-sized mock outcrops comprising a wide range of lithologies and a variety or features. Taken together, our mock outcrops combine to form an integrated series of lithologic and structural representations that cover over 100,000 m^sup 2^ of our campus. How we developed the CGA using resources available to us and how it is being used in our courses is discussed below.

HISTORY OF THE CAMPUS GEOLOGICAL AREA

The CMU Campus Geological Area resulted from the efforts of a number of people over a time span of more than forty years. Thus, the history of constructing our CGA should be relevant to those considering a CGA for their campus.

The earliest portions of the CGA were added to the campus landscape in the 1960's, when geology faculty members convinced the university to bring local glacial erratics to campus for teaching purposes. Like those illustrated by Drummond (2004), these were arranged into a number of large "boulder groupings" in various places around campus. As they appear in Figure 1, several of these groupings remain intact and are part of the CGA. In the late 1980's the department was approached by members of the "Campus Beautification Committee" (CBC) - a committee composed of various faculty, staff, and members of our Facilities Management (FM) group - who wanted our help in selecting a suitable site and rock specimen for an on-campus memorial. For the memorial, we selected one of the largest rocks then on campus - a glacially-scoured quartzite boulder (approximately 1m x 1m x 2m, with an estimated weight or over 5000 kg) - as the centerpiece. The concept was to simulate a glacially scoured outcrop by orienting and partially burying the boulder with glacial straie oriented such that students could correctly establish the direction of glacial advance across the area. Providing detailed instructions during several meetings with the FM supervisors, we left them to correctly place the boulder at the site. Consequently, the boulder was partially buried as requested, but was oriented improperly; the striae incorrectly indicate ice advance from the SW towards the NE.

In the early 1990's two developments facilitated the continuing evolution of the CGA. The first of these was the construction of the new Dow Science building and the remodeling of Brooks Hall, which houses the Geology Department. Adjacent to Brooks, the associated construction of a 400-500 m^sup 2^ greenhouse was completed in the spring of 1993 (see Figure 1). During that summer, and without any notification, the Biology Department began construction of a large boulder garden adjacent to the greenhouse. Through rapid negotiations, several geology faculty became involved in arranging these boulders to enhance geology instruction. As one example, we were able to place three very similar amphibolite boulders cut by granitic pegmatite dikes in a linear array stretching over approximately 30 m to demonstrate the linearity of dikes and foliation (Figure 2). However, had none of our faculty been on campus during the summer, the boulder garden would have been constructed without our input.