Shaping Earth's surface

Field Trip - Lawrence Hall of Science

The Lawrence Hall of Science in the hills above UC Berkeley offers fantastic hands-on workshops and exhibits related to earthquakes and plate tectonics. The middle school program, “Earthquakes: Whose Fault Is It?” provides an excellent introduction to seismology. The program begins with a large puzzle of the Earth’s tectonic plates to introduce the idea of plate tectonics and begin a discussion of the location and movement of the tectonic plates. Students then investigate earthquakes and learn to read real and simulated seismograms. Finally, students use seismic recordings to locate the epicenter of an earthquake. Afterward the workshop, the permanent outdoor exhibit, “Forces that Shape the Bay” provides a free-form venue to explore plate tectonics through hands-on exhibits. The other exhibits and planetarium are also worthwhile.

Field Trip - Marin Headlands

Marin Headlands: photograph of Marin Headlands from the Golden Gate Bridge by Christopher BelandMarin Headlands: photograph of Marin Headlands from the Golden Gate Bridge by Christopher BelandSummary
The Marin Headlands contain the geologic record of a great deal of plate tectonic action that can be used to piece together the history of the formation of California. Briefly, around 180 million year ago, the North American plate collided with a now subducted plate called the Farallon plate. As the Farallon plate dove under the North American plate, bits and pieces of the Farallon plate were scraped off. These bits and pieces can be found in the Marin Headlands in several distinctive rock formations: pillow basalts (at the Point Bonita Lighthouse), chert (near Rodeo Lagoon), and sandstone (at Rodeo Beach). By closely observing these rocks and figuring out how they formed, an understanding of how California itself was formed may be inferred.

Project - Earthquake Towers

Earthquake TowerEarthquake TowerSummary
In this project, students construct drinking straw towers that must withstand the shaking of a shake table. One by one, 250 gram sandbags are loaded onto the towers. The towers must remain standing for 1 minute from the start of the simulated earthquake. Students then have 2 minutes to repair any damage before another sandbag is loaded and the next earthquake test begins. Students quickly learn basic principles of earthquake engineering and architecture as well as the team skills that are a basic part of all science and engineering fields.

Field Trip - Caldecott Tunnel

To apply students’ understanding of the rock cycle and basic principles of stratigraphy, I brought my students to the Caldecott Tunnel to investigate the local geology and piece together the geologic history of their backyard. The east side of the tunnel has an easily accessed road cut that displays a gorgeous example of a contact between older sedimentary rock layers and a more recent volcanic layer. The whole thing has been folded and faulted by the actions of the Hayward Fault, and thus the layers are no longer horizontal but at a sharp diagonal. My students drew pictures of the northern cliff face on the Orinda side of the tunnel then each student was assigned a rock layer to study in detail. When we got back to the classroom, we reassembled the data on the whiteboard, and made theories about the sequence of events that would bring about the rock layers we observed in the cliff. Finally, students drew pictures of what the area must have looked like at different parts of the timeline. This field trip led gracefully into the next segment of the unit on geologic time.

Caldecott Tunnel - north roadcut
Photograph of the northern roadcut face at the Caldecott Tunnel from the field trip “Caldecott Tunnel between Oakland and Orinda” by Russell W. Graymer in "The Geology and Natural History of the San Francisco Bay Area: A Field-Trip Guidebook", edited by Philip W. Stoffer and Leslie C. Gordon.


3. Layers Upon Layers

Grand Canyon

The study of rock layers, or stratigraphy, is a natural way to introduce students to the fundamental principles of geology and to lead into the idea of geologic time. In this lesson, students are introduced to Nicolas Steno’s 3 major laws of stratigraphy: the law of original horizontality, the law of superposition and the law of lateral continuity. Students also add their observations of sediment sorting from previous lessons (Soil Analysis, Erosion Patterns, and the Sediment Study Project) to generate a fourth “law” concerning depositional environment – the tiny grains in mudstone were most likely deposited in very still water like a lake or delta while large gravel in conglomerate was most likely deposited in fast moving rivers and streams. While this activity has students depositing sediments in clear plastic cups or Mason jars, it is recommended that the teacher simultaneously conduct the activity using a squeeze box like the one described by Eric Muller. In this way, when the student activity concludes, the teacher can take the activity further to show how layers can become folded and faulted by plate movements. This lesson is a natural extension of the Going Further activity from the Crayon Rock Cycle lesson where sediments are mixed with sodium silicate to create home-made sedimentary rocks.

2. History of Rock

Every rock holds clues about how it formed. Geologists are like rock detectives who know how to read the clues about a rock’s origins and the stories it can tell. In this activity, students first become specialists in one type of rock. Then, they meet specialists in other rock types to compare their rocks and teach the others about their rock’s history. This lesson is an opportunity for students to consolidate information from the previous lesson on the rock cycle, and begin to think like geologists. Ideally, the rocks selected for investigation are collected from the site of an upcoming geology field trip – such as to the Caldecott Tunnel or Mount Diablo. In this way, students gain experience identifying individual rocks and learning about the way in which each of the different rock types form. Then, on the field trip, students can apply their controlled classroom knowledge to real world geological history.

1. Crayon Rock Cycle

What's the big deal about rocks? They don' move, aren't flashy, and seem pretty useless to the untrained eye. To discover the beauty of rocks, one must look closer and learn how to read them. Geologists are rock detectives, discovering clues to the ancient past. If you know how to read them, rocks can tell an observant scientist about what a place looked like millions and even billions of years ago. This activity introduces the 3 main types of rocks and the processes that form them. Wax crayons are eroded into sediment, compacted into sedimentary rock, partially melted and pressed into metamorphic rock, and finally melted and cooled into igneous rock. This understanding is the basis of the rock cycle. In the Going Further section, there is a recipe for making your own sandstone, siltstone and conglomerate using sediments and a sodium silicate solution.

Can describe the 3 major types of rock (sedimentary, metamorphic, and igneous) and discuss the relationships between them
Can diagram the rock cycle
Given one of the three major types of rock, can describe the geologic processes that formed it

Geology Box

Mt Diablo caves
This box is all about the geology of the San Francisco Bay Area and Earth history. Students will learn about the rock cycle and the types of rocks that form under different conditions. Using this knowledge, students will investigate the rock layers exposed alongside the Caldecott Tunnel (Highway 24). Their explorations will reveal the geologic history of the San Francisco Bay area as it transitioned from ocean, to riverbed, to flood plain, to volcano, and then back to ocean again. In addition, students will research and create a timeline of life on the planet investigating the various life forms throughout the history of our planet and putting our own miniscule existence as human beings into the context of the enormity of Earth history.

7. Erosion Patterns

This lesson is an extension of the GEMS guide: “River Cutters” by the Lawrence Hall of Science (see note below). In the GEMS curriculum, students are introduced to erosion by modeling the formation of rivers in tubs of diatomaceous earth, a silt-like substance into which meandering river channels and deltas form. This lesson builds off of the River Cutters activities by using a combination of sediment types in the models. They observe how gravel and large particles of sand remain in place whereas silt is washed downstream in fast flowing river channels. In contrast, where the water velocity slows as it reaches the newly forming bay, a beautiful silt-covered delta forms. These observations lead students to the conclusion that fast moving water picks up the smaller sediment particles and eventually deposits them in places where the water slows. Students can then take this theory to test it out in real world conditions at a local creek in the Sediment Study Project, observing sediments and water velocity at different sites along a creek’s length. The concept of how sediments are deposited becomes a core feature of subsequent geology lessons and investigations in which the environmental conditions surrounding the formation of large particled conglomerates may be differentiated from small particled shales and siltstones.

GEMS River Cutters

Special Note: This lesson plan is written with the assumption that students have some experience using the river models in the GEMS guide “River Cutters”, written by Cary Sneider and Katharine Barrett and produced by the Lawrence Hall of Science. In this guide, students make observations of rivers carved in just silt (diatomaceous earth), sequencing events in time, noticing patterns, recording information, and acquiring the terminology necessary to describe common erosion patterns. My students completed the first 5 sessions of River Cutters although completing the first 3 lessons is sufficient. So as not to infringe upon the copyright of the GEMS unit, only the extension activity is described here.