Field Trip - Teacher's GuideGuide

SED 695b 695B

Topics addressed

• Layers of Rocks

• Geologic Origins of Locale

• History of Locale

• Various Observational Techniques

Standards: Grade Seven

4. Evidence from rocks allows us to understand the evolution of life on Earth. As a basis for understanding this concept:

a. Students know Earth processes today are similar to those that occurred in the past and slow geologic processes have large cumulative effects over long periods of time.

c. Students know that the rock cycle includes the formation of new sediment and rocks and that rocks are often found in layers, with the oldest generally on the bottom.

e. Students know fossils provide evidence of how life and environmental conditions have changed.

Description of Field Trip

Vasquez Rocks is the result of 25 million years of earthquake activity. From the Oligocene Epoch to the present, earth movement continues along the Elkhorn Fault, an offshoot of the San Andreas Fault. The ancient rock layers have slowly been compressed, folded, and uplifted while erosion has gradually stripped away top soil from around the rocks, leaving spectacular jutting slabs. These intriguing rock outcroppings consist of course-grained yellow-gray sandstone beds several feet thick. Many areas have beds of shale, basalt, and reddish-brown conglomerate layered between the sandstone formations. Today the rock layers sit tilted at angles of as much as 50 degrees, and the largest outcroping rise to a peak nearly 150 feet high.