OVERCOMING THE CURSE OF THE FLATLAND CAMPUS: GIVING A FIELD TRIP EXPERIENCE TO INTRODUCTORY STUDENTS AT CALIFORNIA STATE UNIVERSITY, SACRAMENTO

Exposing beginning geology students to real rocks and structures is a highly desirable part of an introductory geology course. Sacramento, located in the notoriously flat Great Central Valley, lacks bedrock exposures. We overcome this disadvantage in several ways.

For my general geology and physical geology classes, I assign an “On Campus Investigation.” Students, on their own, answer questions about showcase displays in the geology building and the rock garden in front of the building. The building, Placer Hall, was constructed in a unique cooperative venture between CSUS and the U.S. Geological Survey. Shortly after it was opened in 1997, large rocks began appearing in front of building. This grew into an impressive outdoor display that now includes fossiliferous conglomerate, lithified mudcracks, serpentinite, hexagonal basalt columns, folded strata, layered obsidian flows, pahoehoe and a dike in granite. (A pamphlet, produced by the USGS and the Geology Department, describing the rocks is available at the site.)

Our physical geology class is our most rigorous introductory geology course and requires a field trip. I have my students provide their own transportation and meet at a shopping center in Folsom, a 20 minute drive from our campus. There, the geology of the Central Valley meets the geology of the Sierra Nevada. In a short walk we see Cretaceous marine sandstone unconformably overlain by Tertiary stream deposited conglomerate, mechanical and chemical weathering, granite that is crosscut by a mafic dike that has been faulted, quartz veins, spheroidal weathering and active stream erosion. The second part of the trip is optional as it involves strenuous scrambling over large boulders and patches of poison oak. Those that go see the contact zone in which granite has brecciated metamorphic rock during intrusion, a folded and sheared granite dike, contact metamorphic rock, low grade regionally metamorphosed marine sedimentary rock, graded bedding, pillow basalt and Folsom prison, built of granite. The entire tour takes about two hours.