Geology

Class Readings

Is There (Sean Greene, Bay Nature Magazine, 2013) Plate Tectonic Framework (Doris Sloan, Geology of the San Francisco Bay Region, U.C. Press, 2006) Geology – Helpful Definitions Rock Cycle (2 versions) Geologic Time Scale, standard Geologic Time Scale, clock version Geologic Map of Sonoma County Geology Activity: Field Test for Igneous Rocks Geology Activity: Rock to Rock, a fantasy journey Geology Activity: Adopt‐a‐Rock Water Cycle/Watershed Activities by Dr. Rocky Rohwedder CALNAT: Naturalist Handbook Chapter 2

Key Concepts:

By the end of this class, we hope you will be able to: Understand that geology “rocks,” not just because it is about rocks, but because it explains so much about the whole world, Name the three main types of rocks found on Earth and explain the basics of how they form by describing the rock cycle, Understand the connection between geology and groundwater (e.g. Why did the water level in Stuart Creek go up after the August 2014 earthquake?), Recognize obsidian and explain its significance for projectile points and the history of this area, Place Bouverie Preserve in a watershed and get young learners to imagine and discuss human impacts on watersheds, and Convey to 3rd and 4th graders that rocks and landforms can tell us a story about local history.

For Further Study Recommended Reading  Geology of the San Francisco Bay Region by Doris Sloan (U.C. Press, 2013)  Roadside Geology of Northern & Central California by David Alt & Donald Hyndman (Mountain Press, 2016)  Assembling California by John McPhee (Farrar, Straus and Giroux, 1994)  A Land in Motion by Michael Collier (U.C. Press, 1999)  Geologic Trips: San Francisco and the Bay Area by Ted Konigsmark (Geopress, 1998)

Trail Tip Face Painting and Earth to Art! Materials: Small rhyolitic creek rocks of different colors and one slightly larger hard gray rock How: Wet the small, colored rocks (they will be chalky) and rub them on the larger, harder gray rock until a thin paste is formed. Dip your finger into the paste and “face paint” yourself or another student. The natural pigment can also be used for making pictures in field journals. NOTE: Make sure to Leave No Trace by rinsing and replacing rocks when finished with activity. ONLINE RESOURCES  News and Information about geology and earth sciences including a broad survey of geological topics and fun facts at http://geology.com/  The U.S. Geological Survey website has educational materials for teachers and students including lessons, data, maps, and more http://education.usgs.gov  Geology for Kids at http://www.kidsgeo.com/ contains child‐friendly links for information on earth sciences, volcanoes, rocks and minerals. There are similar resources for other topics including Astronomy, Biology, Botany, Chemistry, Ecology, Entomology, Herpetology, Meteorology, Ornithology, Science ‐ Science Fair/Projects, Space and World Science at http://www.kidsknowit.com/  Sonoma County virtual geology field trips with former Sonoma State University Professor Terry Wright (http://www.terrywrightgeology.com/fieldtrips.html Is There Earthquake Weather? And Was That It? by Sean Greene on October 16, 2013

A summer sunset -- having nothing at all to do with -- from Panoramic Hill in Berkeley, just south of the epicenter of Monday's 3.2 quake. Photo: D.H. Parks

I made a $100 bet on Monday that there wouldn’t be an earthquake.

I was eating lunch in the courtyard at the Berkeley Graduate School of Journalism, where I am a student, and a classmate claimed, “This is earthquake weather!”

I told her there’s no such thing, and the bet was on. We shook on our left hands because I was still holding a sandwich.

Twelve hours later, around 1 a.m. on Tuesday, the ground shook. Not much, but enough to make me kick myself. It was a tiny magnitude 3.2, with its epicenter in Tilden Park.

Does weather really cause earthquakes? Is there such thing as “earthquake weather?” Was this week earthquake weather? I called the Berkeley Seismology Lab to ask the experts. The answer from Cal seismologist Dr. Peggy Hellweg was decidedly confident.

“No. The short answer is no,” she said. “No such thing as earthquake weather.”

Warm fall days are what people typically think of as “earthquake weather.” But in reality, earthquakes happen all the time, “so they’re independent of weather,” Hellweg said.

Before humans found out about , we had some interesting ways to explain earthquakes.

Aristotle thought earthquakes were caused by trapped in underground caves.

Hellweg said the Japanese believed there was a big catfish underground that caused earthquakes. In India, legend suggested the earth was sitting on the back of an elephant. When the elephant moved, there were earthquakes.

When we talk about earthquake weather, we’ve probably already got earthquakes on our minds, Hellweg said.

On Monday, there was a 7.2 quake in the Philippines. And few weeks ago, there was a 3.1 centered in Berkeley.

In other words, when there’s one earthquake, people start to notice them more.

“The little earthquakes that you feel are a good reminder to keep your earthquake kit ready,” Hellweg said.

As we’re all busy noticing earthquakes, the Great California Shakeout, the country’s largest earthquake disaster drill, arrives on Thursday — just in time. Every year, the drill falls right in the midst of “earthquake season,” or more accurately, in October.

The drill hits at 10:17 a.m. (The time always corresponds with the date.) It’s timed to remind students returning to school of proper protocol in the event of the “Big One.”

This year’s Shakeout happens to coincide with the 24th anniversary of the Loma Prieta earthquake, a magnitude 6.9 also known as the World Series Earthquake.

While there’s no such thing as “earthquake weather,” it’s unwise to place bets on the likelihood of a quake.

Luckily my classmate forgave the debt. The Hayward Fault is fairly active and there are lots of small tremors happening all the time. That makes for some poor betting odds.

Sean Greene is a graduate student at the UC Berkeley Graduate School of Journalism and a Bay Nature intern.

Some Helpful Definitions

BASALT is a dark, igneous rock.

The Hawaiian Islands are made of basalt. The volcanoes at seafloor spreading centers erupt basalt. ______

CHERT is a hard, sedimentary rock made of silica (glass).

In the Bay Area, chert is colorful, and often forms layers a few inches thick. Bay Area chert is full of microscopic fossils, called radiolarians.

Radiolarian chert is formed on the deep ocean floor. ______

CONVECTION is a type of heat transfer where hot material rises and cooler material sinks, as in a pot of boiling water.

Convection currents in the mantle move the tectonic plates. ______

A CONVERGENT PLATE BOUNDARY is a boundary where two tectonic plates collide, and the Earth’s crust is folded and compressed, or CONSUMED by subduction. ______

The CORE is the layer at the center of the Earth.

The INNER CORE is solid and probably made of iron.

The OUTER CORE is liquid and also probably made of iron.

The core of the Earth is VERY HOT, around 10,000ºF! ______

The CRUST is the Earth’s outer layer. It’s the familiar rock and soil we walk on, and it’s what the oceans rest upon.

Ocean crust is thinner but denser (heavier) than continental crust. ______

A DIVERGENT PLATE BOUNDARY is a boundary where two tectonic plates move apart, and where new crust is created. ______

The FRANCISCAN FORMATION is the name applied to all of the crumpled and mashed seafloor rocks that form most of the Coast Range of California. ______

GRAYWACKE SANDSTONE is a sedimentary rock made of different-colored and different-sized angular sand grains and rock pieces.

Graywacke forms near subduction zones. ______

The MANTLE is the middle layer of the Earth. The upper mantle is gooey, like melting plastic or silly putty.

The deeper mantle is solid. ______

PILLOW BASALT is lava that erupted underwater.

When the HOT lava contacts COLD seawater, it hardens into blobs (or “pillows”).

Most of the pillow basalt found in the Bay Area formed at a seafloor spreading center. ______

RADIOLARIANS are plankton found in the ocean. They are single-celled, with beautiful skeletons made of silica. ______

A SEAFLOOR SPREADING CENTER is a type of divergent plate boundary found in the ocean.

New seafloor is created at seafloor spreading centers.

There are about 43,000 miles of seafloor spreading centers around the world. ______

SERPENTINE (Serpentinite) is a gray, green, or blue slick rock, altered by seawater.

It forms in the upper mantle and squeezes into rock layers like toothpaste.

Serpentine (or Serpentinite) is the state rock of California. ______

SUBDUCTION is the process in which an oceanic plate sinks beneath another tectonic plate.

The Earth’s crust is consumed at subduction zones.

Subduction occurs at convergent plate boundaries. ______

A TECTONIC PLATE is a piece of the Earth’s crust that moves slowly over the gooey upper mantle.

The crust of the Earth is broken into about 12 tectonic plates, which fit together like the pieces of a very big jigsaw puzzle. ______

A TRANSFORM PLATE BOUNDARY is a boundary where two tectonic plates slide past one another. ______

The Rock Cycle

STANDARD GEOLOGIC TIME SCALE

AGE EON ERA PERIOD EPOCH IMPORTANT EVENTS (M.y.) Holocene 0.01 – now Human civilization develops. Quaternary Pleistocene 1.6 - 0.01 Continental glaciation in the northern hemisphere Pliocene 5.3 - 1.6 Humans appear for the first time. CENOZOIC Miocene 23.7 - 5.3 Antarctic Ice Sheet develops. Tertiary Oligocene 36.6 - 23.7 Himalaya Mountains begin to form. Eocene 57.8 - 36.6 The Alps form in Europe. Paleocene 66.4 - 57.8 Mammals become dominant land animals Cretaceous 144 - 66.4 Dinosaurs become extinct; Rocky Mountains begin forming. MESOZOIC Jurassic 208 - 144 Atlantic Ocean begins to form between N. America & Africa. PHANEROZOIC Triassic 245 - 208 1st dinosaurs; begins to separate from Africa. Permian 286 - 245 All land masses joined to form a supercontinent called Pangea. Appalachian Mountains & Ouachita Mountains formed by Pennsylvanian 320 - 286 continental collision with Africa. Mississippian 360 - 320 Extensive deposits of coal developed worldwide. PALEOZOIC Devonian 408-360 1st fossils of amphibians (animals which could live on land). Silurian 438 - 408 1st fossils of land plants. Ordovician 505 - 438 1st fossil fish; evidence of continental glaciation in Africa. Cambrian 545 - 505 Abundant fossils of marine organisms. PROTEROZOIC 2500 - 545 1st evidence of oxygen in atmosphere = 2.0 billion years ago. PRECAMBRIAN 4500 - Earliest evidence of life = 3.8 billion years ago.Earth forms = 4.5 ARCHEAN 2500 billion years ago.

The vastness of geologic time proves to be mostly incomprehensible to us. One useful tool to improve our understanding involves shrinking all of Earth history into a single half-day, with our planet's birth being at midnight, and present time being noon. When reduced thusly, the major events in Earth history play out like this...

4,500 million years ago.

The Earth has formed, along with the other bodies in the solar system, from a of dust and gas swirling around a protostar... our sun. The Precambrian era has begun. 4,125 million years ago.

Still in its infancy, planet Earth has cooled, has almost no free oxygen, and is a very different world from the one we know today. No life forms are yet present. 3,750 million years ago.

The oldest still-existing rocks are just forming (3,690 million years ago). The very first life is just about to appear in the form of simple, single-celled organisms (Eubacteria, Prokaryotae).

3,375 million years ago.

Simple life continues to radiate. The cyanobacteria (blue-green algae) are a dominant lifeform.

3000 million years ago.

The first photosynthetic bacteria appear. All life is restricted to the sea, which provides a fairly constant environment and protection from the sun's ultraviolet rays. With photosynthesis, the levels of atmospheric oxygen begin to rise. 2,625 million years ago.

The end of the Achean eon and the start of the Proterozoic eon of the Precambrian is in sight. The Archaebacteria (unusual bacteria) make their appearance. 2,250 million years ago.

Half of Earth history has elapsed, and the first multicellular organisms are just appearing. The first Eukaryotes arise, beginning with the protists. The first macrofossils (naked eye) will make their appearance in another 50 million years. 1,875 million years ago.

Earth is struck by two massive solar system objects, leaving 140 km craters in South Africa and Sudbury, Ontario, Canada. The first photosynthetic plants (green algae) appear. 1,500 million years ago.

World-wide radiation of photosynthetic aquatic life has significantly altered the composition of the atmosphere. Free oxygen forms ozone, blocking ultraviolet light and paving the way for life on land (although far from immediately).

1,125 million years ago.

Fungi make their appearance (Zygomycota). A mid-continent rift forms in what will become North America.

750 million years ago.

Things speed up as we near the start of the Cambrian period. Brown and red alagae have formed, and the first animals (Annelida) are immediately around the corner. 374 million years ago.

The Devonian period, the Age of Fishes, is here. In the last hour, plants and insects have begun the colonization of the land, and the first amphibians have pulled themselves out of the water. The great Carboniferous forests will shortly arise. Now.

The first reptiles appeared early in the hour, the dinosaurs lived for about 26 minutes later in the hour, and the first hominds appeared about 39 seconds ago. Modern humans have been on Earth for the past 6 seconds or so.

©2007 Terry Wright FieldTest for IgneousRocks. By Scoit Lowyer

Thisis field test thot wosinspired by o fourth gradecloss thot wosinterested in the geologyof the oreo.We werediscussing the DroDerliesof the voriousrocks in the oreoof the viewtroil. I was informingthem fhot the bosolt"bombs" were high in ferro- mognesium(Iron) ond low in silico,(typicol mof ic) vs. the rhyolite tuff whichis opposite, low in ironond higher in silico(typicol felsic).One of the studentsthen osked me if the rockswere mognetic.I couldn't forgive myself for neveractuolly testing thoi. Beingo somewhotprepored field geologistI hoppenlo corry o mognetwith me. We 6eganto tesi lhe rocksin the oreq,ond lowond behold fhe rockscould ottroct the mognet.We conducied this experimentuntil we found the rhyoliteond found the mognet wouldnot stick to theserocks. showinc their lowiron content.

Exercise: Geology, Water, Watershed Page 1 MGP Docent Training 2012-2013

An Apple as the World (From handouts by Rocky Rohwedder, Sonoma State: Docent Training 2000-2001)

Objective To get the children thinking about how much of the earth is habitable, how much water is available for drinking, how much land can grow crops, etc.

Materials  Apples  Knife

Activity Cut the apple into quarters.  ¾ of the Earth’s surface is water  ¼ of the Earth’s surface is land Cut the ¼ representing land in half.  ½ of the land, or 1/8 the total Earth’s surface is habitable. The rest of the land is deserts, mountains, frozen ice caps, and other places people cannot live. Take the piece that represents the habitable land, and cut it into four sections  ¼ of the Earth’s habitable land, or 1/32 of the Earths is where ALL of the Earth’s food comes from. As you are asking the children what would happen if this part of the Earth were damaged or destroyed, you can eat that piece of the apple for effect. Take a small shaving off one of the slices that represents the water of the world.  Less than 1% of the Earth’s water is fresh and drinkable. Most of this water is tied up in the atmosphere () and underground. As you ask the children what would happen if the water was polluted or waster, eat the shaving. This strategy can be a lead-in to an open-ended discussion about taking care of our resources.

This is a good lunch time activity that can incorporate computation, fractions, etc. with a discussion of the portions of the earth actually available to humans and how important it is to be stewards of the land, water, and air.

The figures above are rough numbers that are good for use with an apple. FYI –

Water is 71-72% of Earth, Of that: Oceans 97.2% of total All Icecaps/Glaciers 2.0% Groundwater 0.62% Freshwater Lakes 0.009% Inland Seas / Salt Lakes 0.008% Atmosphere 0.001% All Rivers 0.0001%

A cool thing to point out is that 72% of the person you love the most is water. This is almost exactly the same percentage as the amount of water on the planet. A good lead-in to planetary stewardship. Exercise: Geology, Water, Watershed Page 2 MGP Docent Training 2012-2013

Transpiration (Adapted from ACR’s Bolinas Lagoon Preserve Teacher Packet with additions made by the BLP Training Class of 2002- 2003)

Objective To demonstrate and discuss transpiration

Materials  Plastic Bags  Rubber bands (if not using “zip-lock” bags)

Activity (It is sometimes fun to set this up in the Ranch yard at the beginning of your hike and check out what has happened when you return to the yard at the end of your hike.)

Divide in groups; give each group some plastic bags and rubber bands or zip-lock bags. Have the groups put a plastic bag around a few leaves of a plant, bush, or shrub that is in the sunshine, and seal the bag around the stem. Try putting bags on several types of plants and shrubs. Have people think about what types of leaves may transpire the most. See if their guesses match their results. (This is a good time to explain about hypotheses.) What might cause different plants to transpire at different rates? (For example, many Mediterranean climate plants have waxy cuticles and try to minimize water loss during the hot, dry summers. What about redwoods? What about the leaves of a Buckeye or a Big Leaf Maple? In the fall or winter, when these plants aren’t in leaf – try some of the trees and plants around Skip’s house.)

Return after an hour or so and see what has happened. Before you have the kids look at the bags, have them cup their hands together and blow into them rapidly (without hyperventiallting). When they rub their hands together, they’ll be able to feel that their palms have become moist. You can relate the water that comes out of us when we respire, to the water that comes out of plants when they transpire.

Background Plants have pores in their leaves called stomata through which they exchange gases. (Plants are the opposite from animals, they give off oxygen and take in carbon dioxide … this is an important learning point for kids … life as we know it couldn’t exist without plants.) When the pores are open, water vapor can escape from the plant. You will actually see water droplets forming within the bag. This demonstrates transpiration, which is the loss of water vapor from plants. Some of the loss is valuable, since it serves to cool the plant, just the same as when humans sweat.

(See info from Water Cycle handout to fit transpiration into the big picture.)

Exercise: Geology, Water, Watershed Page 3 MGP Docent Training 2012-2013

The Water Cycle

California Rain & Snow:

It rains and snows an average 193 million acre feet each year.

Of that, the sun drinks an average 121 million acre feet in evaporation & transpiration.

Of the 72 million acre feel left,

32% goes back into the ocean

31% goes into farming

29% goes to the environment

6% goes to cities & industry

2% runs off to Nevada

Exercise: Geology, Water, Watershed Page 4 MGP Docent Training 2012-2013

Watershed Background: Precipitation that doesn’t sink into the ground or evaporate is surface water. This water becomes runoff, which flows into streams and eventually to the oceans to continue circulating in the hydrologic or water cycle. The entire land area that delivers water, sediment, and dissolved substances via small streams to a larger stream (or river), and ultimately to the sea is called a watershed, or a drainage basin. At the base of a watershed are often wetlands that form in the flood plain. When you are at the Ranch, spend some time exploring the bog in Volunteer Canyon, or walk out the path on the other side of the Scheerin Bridge toward Highway One. Notice the different types of plants that you can find in these areas.

Ask, How do people use rivers? (drinking water, other fresh-water needs, agriculture, industry, manufacturing, power, transportation, recreation) How does wildlife use rivers? (food, habitat).

All the water that enters a watershed always flows within that watershed. That means that what people put into the water, and how people use the water available to them, is very likely to affect the quality of the water—and its users—both locally and in other areas of the watershed. This is one of the reasons that there has been a movement to restructure land management and political jurisdictions to better reflect watersheds.

Some questions to ask when hiking in a watershed:  Where are the driest areas on the hillsides and in the canyons? Where are the wettest?  Are the trees and other plants different in these different areas?  Can you see examples of erosion – of water running off the surface and carrying dirt with it?  Why do we dig waterbars in our trails at ACR?  Are there any plants that indicate the presence of underground springs? Where on the preserve do you find these?  Where does the water at Bolinas Lagoon Preserve Flow? Where does this water come from?