USE OF LARGE SCALE ROCK SAMPLES IN INTRODUCTORY EARTH SCIENCE AND PHYSICAL GEOLOGY COURSES

Students living in geological terrains such as Florida where there is only one type of rock, usually not exposed at the surface, and with no outcrops of structure and bedding are at a distinct disadvantage when learning about the different types of rocks. Earth Science and Physical Geology labs typically give students small (less than 5cm) samples for rock identification. These very small samples do not accurately reflect the size, texture, and larger scale features of rocks in natural settings.

In order to introduce students to more realistic geologic samples a Science Courtyard at the Hillsborough Community College Dale Mabry Campus was created. Large samples of each of the three types of rocks were grouped in three corners. The fourth corner has a waterfall and pond with natural vegetation useful for the Environmental Science and Biology courses. Examples of ripple marks, bedding, and graded bedding are displayed in the sedimentary rock samples. A lab assignment specifically using the samples in the courtyard has been developed as an introduction to rocks and minerals. This lab requires students to sketch the mini-outcrops and describe the samples much as they would at a natural outcrop. The “rock garden”, as the area has come to be called, replaces what was previously an empty, weed-infested area that was not successful in growing plants because of the lack of sunlight and water.

Although the ideal situation would be to take introductory Earth Science and Physical Geology classes on field trips to several locales that have outcrops of the three different types of rocks, it is not practical because of the distance, cost, and lack of suitable sites. Community college students typically work and have family commitments preventing them from participating in field trips. The HCC rock garden provides a means for the students to be able to visualize and experience different types of geology that would be otherwise not available to them.