A field trip to explore rock formation and tectonics of southern California
This activity has benefited from input from faculty educators beyond the author through a review and suggestion process.
This review took place as a part of a faculty professional development workshop where groups of faculty reviewed each others' activities and offered feedback and ideas for improvements. To learn more about the process On the Cutting Edge uses for activity review, see http://serc.carleton.edu/NAGTWorkshops/review.html.
This page first made public: Dec 8, 2011
Skills and concepts that students must have mastered
- Basic mineral and rock identification
- Exposure to the geologic time scale
How the activity is situated in the course
- Field trip in petrology or earth materials course
- May also provide opportunity for sample collecting for individual term projects
Content/concepts goals for this activity
Higher order thinking skills goals for this activity
- Formulation of petrologic hypotheses from the identity and diversity of rocks
- Synthesis of hypotheses at later stops as diversity of rocks continues to increase
- Development of a hand sample analog of the time scale integrated from all stops
Other skills goals for this activity
Description of the activity/assignment
The diversity of ages and types of crystalline rocks makes a field trip through either or both of these ranges a great opportunity to engage students in active learning while linking petrology and historical geology course content in a field context. Students can utilize rock identification skills learned in the laboratory, and with knowledge of available geochronologic data, can construct a more detailed geologic time scale for the region.
Here we will provide an example of a one-day trip to examine Proterozoic metamorphic and Mesozoic intrusive igneous rocks that are easily accessible in roadcuts and on short field traverses along National Forest roads. The trip is adapted from more detailed field guides and road logs for this region (principally Barth et al., 2001), with a focus on undergraduate learning.
Determining whether students have met the goals
I also integrate samples from selected stops in later laboratory practice tests
Download teaching materials and tips
Barth, A.P., 1990, Mid-crustal emplacement of Mesozoic plutons, San Gabriel Mountains, California, and implications for the geologic history of the San Gabriel terrane, in Anderson, J.L. (ed.), The Nature and Origin of Cordilleran Magmatism: Geological Society of America Memoir 174, pp. 33-45.
Barth, A.P., Jacobson, C.E., and May, D.J., 1991, Mesozoic evolution of basement terranes of the San Gabriel Mountains, southern California: Summary and field guide, in Walawender, M.J., and Hanan, B.B. (eds.), Geological Excursions in Southern California and Mexico: Geological Society of America, pp. 186-198.
Barth, A.P., Jacobson, C.E., Coleman, D.S., and Wooden, J.L., 2001, Construction and tectonic evolution of Cordilleran continental crust: Examples from the San Gabriel and San Bernardino Mountains, in Dunne, G., and Cooper, J. (eds.), Geologic Excursions in the California Desert and Adjacent Transverse Ranges: Pacific Section, Society of Economic Paleontologists and Mineralogists, Book 88, 17-53.
Barth, A.P., Anderson, J.L., Jacobson, C.E., Paterson, S.R., and Wooden, J.L., 2008, Magmatism and tectonics in a tilted crustal section through a continental arc, eastern Transverse Ranges and southern Mojave Desert, in Duebendorfer, E.M., and Smith, E.I. (eds.), Field Guide to Plutons, Volcanoes, Faults, Reefs, Dinosaurs, and Possible Glaciation in Selected Areas of Arizona, California, and Nevada: Geological Society of America Field Trip Guidebook 11, 101-117.