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Activities in Lesson: What is Geology? (10 min) Ride the Rock Cycle (25 min) Which Rock is Your Rock? (20 min) Hard as a Rock (30 min) Geology Bingo (15 min) Chip Mining (15 min)

Time: 1 hour, 55 minutes

Erosion– the group of natural processes, including weathering, dissolution, abrasion, corrosion, and transportation, by which ma-terial is worn away from the Earth's surface. Geology—the scientific study of the origin, history, and structure of the earth. Glacier– a huge mass of ice slowly flowing over a land mass, formed from compacted snow in an area where snow accumula-tion exceeds melting and subli-mation. Igneous- type of rock formed by solidification from a molten state. Lamina— A narrow bed of rock. Luster — The appearance of a mineral surface judged by its bril-liance and ability to reflect light. (metallic, earthy, waxy, greasy, vitreous/glossy, adamantine/brilliance as in a faceted dia-mond) Metamorphic– type of rock changed in structure or composi-tion as a result of pressure/heat/chemical change.

Mineral– a naturally occurring, homogeneous inorganic solid substance having a definite chemical composition and char-acteristic crystalline structure, color, and hardness. Rock– relatively hard, naturally formed mineral or petrified mat-ter; stone. Sedimentary– of or relating to rocks formed by the deposition of rock and mineral particles. Specific Gravity — The ratio of the mass of a solid or liquid to the mass of an equal amount of distilled water at 4º Celsius. Tectonic Plate– pieces of the Earth’s crust and uppermost mantle (referred to as the litho-sphere) that move, float, and sometimes fracture. Their inter-action causes continental drift, earthquakes, volcanoes, moun-tains, and oceanic trenches.

Vocabulary

Objectives: The students will name and

show examples of the three main classifications of rock.

The students will explore vari-ous ways that the surface of the earth changes due to wa-ter, wind, glaciers, sedimenta-tion, and tectonic plate theory (earthquakes and fault lines).

The students will be able to explain the rock cycle.

The students will give exam-ples of minerals.

Equipment:

Pencils, clipboards, paper Hard as a Rock Chart Rock ID chart Mineral detective sheet Rock Test Kit (HCl, streak

plate, magnet, penny, nail, glass plate)

Hand lenses BINGO cards/chips Rock sample kit Chocolate Chip Cookies Toothpicks; napkins or plates Play money

Note to Teacher: This lesson begins with activities that help explain geology and what a geologist is. The lesson progresses to provide examples of geology that we can see, rock out-croppings, etc., then geology that we can not see, such as the cen-ter of the earth. The lesson culmi-nates with the methods, namely mining, used to obtain these rocks and the minerals that make them up from their natural environ-ments.

Concepts: The surface of the earth changes over long periods of time as a result of many forces.

Rocks are classified into three categories based upon how they have been formed.

Rock and soil formation is a cyclical process that occurs over many millions of years.

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What is Geology? (10 min)

1. Begin by asking the students: What is geology? (The most common an-

swer to this question will probably be the study of rocks and minerals. Another com-mon answer might be: the study of the earth, or the study of how the earth is formed.)

What does a geologist do? Where do geologists work? Can geologists always see what they study? Does what they study always remain the

same? 2. Begin to get the students to think about the shape of the land. Has it always been the same shape? What are some ways either by acting on the surface or from underneath the surface of the earth, the geography of land has changed (either natural or human)? (Some an-swers might include: wind storms, glaciers, sed-imentation, rain, earthquakes, volcanoes, mountain formation, rivers flowing through can-yons, or human activity such as mining, con-struction or farming.) As each student names a force that shapes the earth, ask the student to describe exactly how that force works. For ex-ample:

Wind storms: May loosen soil particles from a hillside and blow them into a stream.

Rain: When on a rock face, may break off some pieces of rock.

Glaciers: Moving slowly over a landscape over thousands of years will scrape up rocks as it moves and then leave those rocks where it melts.

3. Help the students identify wind storms, rain, human activity such as construction, and move-ment of large bodies of water (river, streams, and lakes) as causes of erosion. Help the stu-dents identify volcanoes, earthquakes and mountain formations as the result of magma and plate movement under the Earth’s surface. 4. Ask the students to think about those three forces: erosion, plate movement and magma flow. Of which they would observe the most evi-dence on Indiana’s landscape? Have them think about how they know this. 5. Ask the students to look for sources of ero-sion as they travel around today. Tell them that

for each source of erosion they see they will receive a point, and see who can get the most points by the end of the lesson. **Note: A good location would be any area near a ravine or steep hill (Sunshine Trail), possibly with exposed bedrock and/or Sycamore Creek or an in-termittent streambed. It also would be preferable to be in an area near a trail that slopes down a hill to demonstrate erosion caused by human use of an area.**

Ride the Rock Cycle (25 min) (Adapted from Illinois State Museum Geology Online http://geologyonline.museum.state.il.us) Materials: paper, pencil, rock cycle blocks/cards 1. Talk about the various stages that rocks go through during their journey here on earth. See background about how rocks change and move over and around the earth. 2. Set out cards and corresponding blocks in a large playing area. 3. Each student starts at a different station. They should write down the station they've started at. Then they roll the die and write down where they move to (the location written on the side facing upward), and proceed to their next station. (Upon rolling they may have to stay at that station and should go to the end of the line so others have an opportunity to roll.) 4. Once they have gone through the designated stations (seven rolls of the dice), bring the whole group together to discuss how they have gone through the rock cycle.

Which Rock is Your Rock? (20 min) Materials: pencil, paper, clipboard, hand lenses. 1. Have each student select a rock from within a given boundary. The rock they choose should be small enough to fit in their hand. Once eve-ryone has selected a rock, have the students gather together again. 2. Tell the students that geologists spend time carefully looking at their specimens in order to determine ways to explain things about them. Ask them: what are some ways they may do this?

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3. Have them use more than just their eyesight to create a description for their rock. They should consider size, weight, color, shape, etc., when writing their descriptions. 4. Students should then place their rock in one pile and their description (folded up) into anoth-er pile. When all of the descriptions and rocks are in their piles, let each student grab a de-scription and begin to detect the appropriate rock. 5. After everyone believes they have the appro-priate rock, go around in a circle and have each student read the description and show the rock they selected. The owner of the description can only tell them if they are correct or not, they should not point to the correct rock until after everyone has had a turn to read their descrip-tions. 6. Next, have the students gather up their re-maining rocks and put them into pairs. You will then remind them that they are still playing the role of geologists. They have had practice de-scribing their rocks and now they will have prac-tice classifying their rocks. 7. Ask them how they could classify rocks. Have them write down some of these ideas. With each pair using all of the rocks they have, they will need to come up with ways to classify their rocks. Examples might be: rocks that are dark in color and rocks that are not, rocks that are heavy and rocks that are light, or rocks that fit in the palm of your hand and rocks that do not. 8. Students should make lists of the ways they classified their rocks on one piece of paper and have another piece of paper with two circles drawn on it. With this they can physically place the rocks into the different classes. 9. Tell each group they should have at least 10 different classifications and that they will be asked to share their methods of classification.

Hard as a Rock (30 min) Materials: rock/mineral testing kit, rock sample kit, hammer, hard as a rock chart, rock ID sheet. **Note: A good location is the banks of Sycamore Creek or Fern Valley in the intermittent streambed.**

1. Review with the students how rocks are formed. Show an example of each and teach them the rock cycle song or play geology “rock, paper, scissors.”

Igneous rocks are formed as hot magma cools after it is released through a volcano or is pushed by tectonic plate movement toward the cool crust of the earth. Igneous rocks are found in areas where volcanoes are currently active or where volcanoes were active many thousands or millions of years ago.

Sedimentary rocks are formed over time as layers of pebbles, sand and silt are de-posited in an area and compressed. Often sedimentary rocks are formed under water.

Metamorphic rocks are formed when heat from magma and/or pressure from plate movement change one kind of rock into an-other. Metamorphic rocks are often found in mountainous areas.

2. Divide the students into pairs or small groups. Hand each group a rock from the sam-ple kit—make sure each rock is labeled with a letter/number. 3. The students will fill in the information on their “Hard as a Rock” chart. The students will be recording information regarding the proper-ties of their rock that can help in the identifica-tion process. They will also be using the Quick Rock Key to determine whether or not the rock may be an igneous, metamorphic or sedimen-tary rock. 4. To test for smell: Have the students simply smell the rock with their noses and write down if it has an odor or not. If so, have them write what they think it smells like. 5. To test for color: Have the students note the colors they see in the rock. 6. To test for luster: Have the students hold up the rock to the sun and see if they notice any sparkling, or if the rock still remains dull. Have them record the amount of luster that exists. 7. To test for feel: Have the students hold the rock with their eyes closed and write down how the rock feels. 8. To test for streak: The students will use the

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white porcelain streak plate, making a single scratch on the plate with each rock. Have them record the color of the residue left behind. 9. To test for magnetism: The students will use the magnet provided to determine if any of the rocks contain a metal. 10. To test for weight: The students should choose another pair’s rock for comparison pur-poses and note the number of that rock on their sheet. The students should then hold this benchmark rock in one hand and their test rock in their other hand, then decide which one feels heavier. In the weight column the students should mark an arrow pointing upward if the rock feels heavier than their benchmark rock on downward if the rock feels lighter than their benchmark rock. 11. To test for hardness: The students should use the scale at the bottom of their paper for this test. On the Moh's Scale of Hardness, a rating of 1 is the softest and a rating of 10 is the hardest. If the rock can be scratched easily with a fingernail, the rating is 2.5 or below. Rocks that can be scratched easily with a copper pen-ny have a rating of 3.5 or below. A rating of 5.5 or lower can be given to rocks easily scratched with a nail. The glass will be scratched by a rock of 6.5 hardness or higher.

12. To test for fizz: The students will drop a small amount of an acidic solution (HCl) on each rock and record whether or not the solu-tion fizzes like soda pop. If the solution fizzes, the rock contains calcium and is most likely limestone. 13. After everyone has completed their charts, it is time for them to identify their rocks. Have them use the Rock ID sheet to fill in their rock’s letter/number above the description that most closely matches their findings. Have each group determine through this sheet and their investi-gations, the names of their rocks. 14. Go over the correct answers with the stu-dents. Have them count the number of igneous, metamorphic and sedimentary rocks they have found. If using rocks they found in the area, the majority of the students’ rocks will be sedimen-tary because most of the bedrock in this area is sedimentary. The students will probably not find

any limestone, as the bedrock at Bradford Woods is mostly mudstone or siltstone. Any ig-neous rocks found in the area were probably transported to this area by the Illinoisan glacier. The students may find a few metamorphic rocks, but this is fairly unlikely. Repeat this process with the rocks students found for the previous activity as well as with other sample kit rocks, as time permits.

Geology Bingo (15 min) Materials: Bingo cards, question sheet, Bingo markers (cards and markers can be found on the R:

drive, under “ee” in the “instructor resources” folder, entitled “Geology Bingo”) 1. Explain to your students that this activity will be a chance to share what they’ve learned —by playing Bingo. Hand out a Bingo card to each student and make sure everyone has access to the markers. (You can also do this as a paired activity) 2. The object of this activity is to cover enough squares on the card to get a “bingo.” This can be achieved by covering a row across, a col-umn down, the diagonal stripes from corner to corner, all four corners, or a postage stamp (the four squares in the top right corner). 3. Read a question from the sheet and ask a student with his/her hand raised to answer. Once the correct answer has been provided, everyone may place a marker on that square on their bingo card. 4. When a student has a “bingo,” they shout out “Bingo!” Continue play until all of the questions have been answered. At the end of the activity, review any terms that were difficult for the stu-dents to recall.

Chip Mining (15 min) Materials: chocolate chip cookies, toothpicks, play money, plates or napkins. 1. Begin by asking the students:

Why does it matter if we know this rock con-tains specific minerals?

What good are the minerals? What do we use minerals for? How do we get minerals from the rocks?

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stone=chalk, zinc oxide=sunscreen, box of phosphorus and sulfur=matches) and cons of mining (habitat destruction, water pollution, earth scars, elimination of minerals). Discuss with the students that we need minerals but we also need to protect the earth, and have them come up with ideas to accomplish both.

2. Discuss a few products that we use that re-quire minerals that must be mined. For example we use toothpaste with fluoride, and fluoride comes from the mineral fluorite. 3. Explain to the students that we use natural resources, including minerals, to create things we use on a daily basis and that is not likely to change. However, it is important to share with the students that consumption levels can be changed. Discuss this issue briefly with your students. Remember at Bradford Woods we teach our students how to think, not what to think. 4. Tell the students that these minerals are mined from the Earth and that it is very im-portant that mines are operated safely and re-sponsibly. Today the students will get the chance to be miners. They are going to be min-ing for gold nuggets. 5. As you pass out the cookies, have them look carefully at where the chocolate chips are locat-ed. Have the students imagine those chips are nuggets of gold you want removed from the earth (cookie) with your tools (toothpicks) to use in your jewelry factory. They will be paid $500.00 for each whole nugget (chip) they mine. 6. To make sure you take good care of the earth, you will have to pay a $100.00 fine for every broken cookie piece that is larger than a pencil eraser. 7. Pass out the play money as nuggets are mined and take back money when the earth is damaged. 8. Discuss how much they earned in the chip mining project. Ask the students how their Earth looked after the mining process. Ask if they think this is true of real mining practices. 9. Discuss mining. Have the students list the pros (have them list or discuss some items in their everyday lives that are made out of materi-als that come from the earth, for example: cal-cium=milk, sodium chloride=salt, fluo-ride=toothpaste, clay pellets=cat litter, diamond dust=on finger nail files, box of phosphorus, magnesium, zinc, copper, iron, and calci-um=Cheerios cereal, graphite=pencils, lime-

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Evaluation: √ Students can name and show examples of

the three main classifications of rock. √ Students can state various ways that the sur-

face of the earth changes due to water, wind, glaciers, sedimentation, and tectonic plate theory (earthquakes and fault lines).

√ Students can explain the rock cycle. √ Students can give examples of minerals that

we use in daily life. Keep in Mind: It is not important that your students can cor-rectly identify every rock they pick up; however, it is important that they understand that there are similarities and differences between rocks, in their make up and composition as well as their creation. When doing the last activity that concerns min-ing, remember that we want to provide students with the facts in a non biased approach.

Back in the Classroom Investigate and map fault lines in your commu-nity. Read accounts of the earthquakes in Indi-ana and of the earthquakes that have affected Indiana. Prepare a display for your school teaching others what they should do to prepare for an earthquake, what they should do during an earthquake, and what they should do after an earthquake. Indiana has had powerful earth-quakes in the past and probably will again.

Notes:

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Background

What is Geology? The Merriam-Webster dictionary defines geolo-gy as, “a science that deals with the history of the earth and its life esp. as recorded in rocks; a study of the features of a celestial body (as the moon); the geological features of an area (17) .” Geology is a broad subject encompass-ing not only the identification of rocks and min-erals, but also the movement of the Earth’s plates or seismic activity (talked about so fre-quently in the news following an earthquake).

What Activities Shape the Earth? Windstorms Glaciers Sedimentation Rain Earthquakes Volcanoes Mountain formation Rivers flowing through canyons Human activity such as mining, construction or farming High mountains and deep valleys make the sur-face of the Earth rough and uneven. It seems to us that the Earth’s surface does not change, but most of the mountains and the valleys we see today are really the result of changes. These changes happen so slowly that we are not aware of them. Some changes, however, take place rapidly.

Volcanoes Volcanoes cause the most rapid changes in the Earth’s surface. Pockets of hot melted rock, called magma, in the Earth are the beginnings of volcanoes. Pressure caused by the weight of rock above these pockets or by gas and steam push the hot liquid upward. When a crack de-velops in the solid rock above the pocket, the hot liquid is forced up through it. When the liq-uid rock is forced out, we say a volcano ex-plodes or erupts. The melted rock flows over the surface of the Earth and again becomes solid rock. Gradually, a mountain builds around the opening.

What is an Active Volcano? Volcanoes that send out melted rock or spout smoke and fire are called active volcanoes. When a volcano sends out melted rock, it is

said to be erupting. This hot, flowing mineral is called lava when it appears above the ground. Some active volcanoes spout smoke and fire for years but never erupt. They are still consid-ered active volcanoes. The opening through which smoke, fire, and lava come is called the mouth or crater. Some-times the lava bubbles and boils in this crater and does not overflow. The boiling lava causes steam and smoke to appear around the top of some volcanoes. Volcanic eruptions are not always alike. Some-times lava flows slowly and quietly out of the crater. Sometimes terrible explosions blow it high into the air. How it erupts depends on the amount of pressure forcing the lava out of the crater.

What is a Dead Volcano? A volcano is said to be dead when it has been quiet for so long that no one expects it to erupt again. Dead volcanoes do not always stay dead. Sometimes, after they have been quiet for many years, they start erupting again. Some of the worst eruptions have been of volcanoes that everyone believed were dead. Scientists can never be sure that a volcano is dead and because of this they would rather say a volcano is dormant.

Where are Volcanoes Found? Most volcanoes are found near the coasts of continents. The west coasts of North and South America contain all the volcanoes of these two continents. In Africa; the volcanoes are near the shores of either the Indian or Atlantic oceans. There is also a belt of volcanic islands in the Pacific Ocean, along the coasts of Asia, Aus-tralia, and New Zealand.

Destruction Caused by Volcanoes Volcanoes have caused much destruction in the world. Many people lose their farms, houses, vineyards, and their lives due to volcanoes. However, because the ground is so fertile peo-ple often return to their homes when the erup-tion is over.

Useful Products of Volcanoes Volcanoes can cause much damage and de-

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struction, but in the long run they also have benefits. The physical breakdown and chemical weathering of volcanic rocks have formed some of the most fertile soils on Earth. Most of the metallic minerals mined in the world, such as copper, gold, silver, lead, and zinc, are associated with magmas found deep within the roots of extinct volcanoes. Rising magma does not always reach the surface to erupt. Instead, it may slowly cool and harden beneath the volcano to form a variety of granite rocks. Oil and natural gas are the products of the deep burial and decomposition of accumulated or-ganic material in basins beside mountain rang-es formed by plate-tectonic processes. Hot springs, heated by volcanic heat, help heal some diseases. Hot springs are also used for bathing and laundry purposes in some coun-tries. In some places, there are experiments in which volcanic steam is used. This is called ge-othermal energy and is used to run factories and plants. Geothermal heat warms more than 70% of the homes in Iceland, and is also used to produce electricity to meet the power needs of large cities. Another product of volcanoes is pumice. Pum-ice, a kind of volcanic rock, is used for grinding and polishing. Some Native Americans used obsidian, another kind of volcanic rock, for tools. Sulfur is also found near volcanoes.

Mountains Mountains are formed in several different ways. One way is by the eruption of a volcano. This is the fastest way a mountain can be formed. The making of mountains in other ways sometimes takes thousands of years. Folding is another way mountains are formed. Folding is a gradual pushing up of the Earth’s surface by great pressure on the sides of rock layers. This pressure bends the layers of rock upward like an arch. Faulting is yet another way mountains are formed. Instead of bending under pressure, the rock layers break and form mountains. As the rock breaks, the edges rise sharply above the

ground. This makes mountains that are steep on one side and sloping on the other. Other mountains are made when magma push-es between layers of rocks and makes them rise above the ground. Mountains supply water for many people who live in valleys and plains. The snow and ice on mountains melt in the warmer seasons and the water runs down the slopes as clear, cold mountain streams.

Earthquakes Have there been earthquakes in Indiana? Yes. There have been seismic waves generated by powerful earthquakes in the past and there probably will be again. There were three major earthquakes recorded over the winter of 1811-1812 in New Madrid, Missouri. These earthquakes all registered with a magnitude greater than 8.0. The shocks were felt all over the Midwest, including Indiana. In early 1812, two powerful quakes occurring near and in the small town of New Madrid in what is now southeastern Missouri shook the earth with enough force to cause church bells to ring in Washington, D.C. They were strongly felt throughout Indiana and were even felt a thou-sand miles away in Boston. Evansville experienced damage from an 1895 earthquake (estimated magnitude 6.2). The strongest earthquake with its epicenter in Indi-ana happened in 1899, near Portersville in Du-bois County. That earthquake had a magnitude of 5.2. In 1987, Indiana residents may have felt an earthquake (5.0 magnitude) centered near Lawrenceville, Illinois, just west of Vincennes. Most recently, Southwestern Indiana felt an earthquake at 5:36 on April 18, 2008. The earthquakes epicenter was in Mt. Carmel, Illi-nois, about 38 miles northwest of Evansville, and it registered a 5.2 magnitude. It was felt here at Bradford Woods! Earthquakes in Indiana in the past 200 years or so have been minor events but there is re-search that has shown substantial earthquake activity thousands of years ago.

Background

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The main theory that guides geologists when studying earthquakes is that of plate tectonics. This theory says that the continents and oceans are sitting on movable plates. These plates move by convection currents and when two plates are pushed together so tightly and the stress becomes too much, they slip and the re-sult is an earthquake. The area where the two plates build up pressure and then slip is the fault line. The currents that move the plates of the Earth may also cause rips in the plates themselves. If a continent is over such a rip, it will also rip. The Mississippi River Valley was formed by several attempts at rips. None of the attempts managed to break the crust of the Earth but the movement did create several fault lines, one being the New Madrid fault. There are few faults near the surface in Indiana but there are many deeply buried faults. Geologists have no way of predicting earth-quakes yet, but they can look at how a particu-lar area may react to an earthquake based on the soil composition.

Prehistoric Indiana Earthquakes The point on the Earth's surface directly above the center of an earthquake is called the epi-center. During the last two centuries, earth-quakes with epicenters in Indiana have been relatively minor events. This has not always been the case. Geologists have recently discov-ered evidence that suggests the occurrence of at least four major earthquakes with epicenters in Indiana within the last few thousand years. One of these quakes occurred near Vincennes about 6,000 years ago and has been estimated to have been many times more powerful than the 6.7-magnitude quake that struck the Los Angeles area in January 1994.

What Causes Earthquakes? An earthquake is a shaking of the Earth caused by the sudden release of energy that results when two bodies of rock in the Earth's crust are under so much stress that they suddenly break and slide past one another. The area of contact between the two bodies of rock is called a fault, and the direction of motion of the bodies may be horizontal, vertical, or a combination of these motions. The force that causes the stress within

Background

the rock is a result of the movement of giant sections of the Earth's outer layer. According to the theory of plate tectonics, the outer layer of the Earth is divided into huge plates, like a cracked eggshell. Convection cur-rents, which permit heat to escape from the Earth’s interior, move the plates at a rate of about one to ten inches per year, carrying with them continental landmasses and the ocean floor. Sometimes the convection currents that cause the plates to move will cause them to rip apart. If a continent happens to be sitting over the tear, then it too will be torn, or rifted, apart. This rifting apparently occurred nearly 600 mil-lion years ago and then again about 100 million years ago. The drifting apart of the rocks caused the formation of many faults that remain as a zone of weakness in the Earth's crust. Compressional forces acting on the North American plate are causing movement, earth-quakes, along the faults.

Earthquake in Indiana’s Future? The ability to accurately predict earthquakes is not yet possible, but seismologists have made progress in assessing the probability of an earthquake occurring in a certain region within a given number of years. With the use of data from the historical record of earthquakes in the U.S. mid-continent, it has been predicted there is an 86% to 97% chance of a 6.3-magnitude earthquake occurring in the New Madrid zone within the next 50 years.

Glaciers Glaciers can be thought of as rivers of ice, slowly flowing from their source to their final destination. Rates of ice flow range widely, but it is thought that the glaciers that affected Indi-ana probably moved relatively rapidly because they had abundant water at their bases to help lubricate their sliding motion over their beds. This sliding motion allows a vast amount of old-er rock and sediment to be eroded from the bed of the glacier, where it becomes frozen into the lower part of the ice. In Indiana, countless tens of feet of soil and bedrock were stripped off the landscape and re-deposited down-glacier, along with even larger quantities derived from areas farther north. It is not surprising that the deposits of Ice Age glaci-

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ers are the dominant materials in the Indiana landscape today.

Ice Age The ice age refers to the period of geologic time encompassing the past 2 to 3 million years or so when the Earth's higher and mid-latitudes experienced widespread glaciation by huge continental-scale ice sheets. The ice age is the most recent of several periods of widespread glaciation that have affected the Earth. The ge-ologic record indicates that major episodes of glaciation occurred at least as far back as 2.4 billion years. The global climate during the Ice Age was much colder than the mild one we inhabit today. The best evidence suggests that, globally, the average air temperature was cooler by some 6 to 12 degrees Celsius, and daily temperature at Indiana latitudes fluctuated seasonally almost as much as they do today. There is little doubt that global weather patterns were substantially different, causing large regions in northern and eastern Canada to receive massive amounts of snowfall and to remain below freezing most of the year. Year after year, the layers of unmelted snow continued to compact into dense ice un-der their own weight, forming ice caps similar to those of Antarctica today. These great land-masses of ice began to flow under the stress of their own weight, and the continental sheets were born.

The very first ice sheet that entered Indiana ap-pears to have arrived before 700,000 years ago and came straight from the north (what is now Michigan). We know this because the sedi-ments associated with this earliest glacier are choked with fragments of coal, sandstone, and distinctive reddish claystone, all rocks that come only from the center of Michigan. Ground water supplies some 90% of the Indi-ana population with all water used for domestic consumption and associated economic activity, and nearly all of the major aquifers that yield this ground water are a direct consequence of glaciation. The major rivers where our commu-nities have been established and the utilization of them for our major recreational resources are all former glacial rivers that drained the melting ice sheets.

Local Ice Age Remnants Bradford Woods The silt deposits and stream systems at Brad-ford Woods are results of the Illinoisan glacier, which melted in this area and washed soil into the White River Valley. Martinsville Martinsville is situated in a several-mile-wide plain of sand and gravel deposited by glacial meltwater flowing down the White River Valley. Bedrock hills of siltstone can be seen protruding through the outwash at several places. The sand and gravel is a major source of groundwa-ter for many communities, such as Martinsville and Indianapolis. The large ridge that the road ascends just north of Martinsville is the remnant of a large outwash fan deposited by an ice sheet of Illinoisian age, some 300,000 years ago. Morgan-Monroe County Line, Bryants Creek The county line marks the approximate extent of glaciers in south central Indiana during the Ice Age. The slope to the west of the road is underlain by up to 50 feet of glacial deposits plastered in the bedrock hill. Bryants Creek formed along the margin of this glacier and con-tains abundant far-traveled rocks, such as gran-ite, that were carried from Canada by the ice.

Rocks If the rock is an Igneous Rock:

It may be colored. It may have shiny flecks of mineral crystals

in it that reflect light (look at rock with hand lens).

The different colored minerals in the rock will be stuck together in no particular pat-tern.

These are formed either from magma liquefied and then cooled deep within the earth, called intrusive, or from lava spewed as liquid from volcanoes and then cooled on the Earth’s sur-face, called extrusive. Examples include gran-ite, basalt, and pumice.

If the rock is a Metamorphic Rock:

It may be many colored. It may have shiny flecks of mineral crystals

that reflect light. The different colored minerals in the rock

will form a pattern of stripes, spots or swirls.

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Background

These are formed when igneous or sedimentary rocks are subjected to changes in the Earth’s pressure and/or temperature. Changes may occur when igneous rocks within the earth are subjected to the movement of the Earth’s plates in mountain building regions or when igneous or sedimentary rocks are near areas of volcanic activity. If the rock is a Sedimentary Rock:

It will look as if it has layers. It may have fossils in it.

These consist of particles worn from pre-existing rocks and then deposited on sea or riv-erbeds. Water pressure causes these particles to cement together along with mud, silt and oth-er organic matter. These rocks all form in layers and break along layered surfaces. Fossils are almost exclusively found in this type of rock from plants and animals trapped in the sedi-ment layers. Examples include limestone, flint, and shale.

Types of Rocks Dolomite

Color is often pink or pinkish and can be

colorless, white, yellow, gray or even brown or black when iron is present in the crystal.

Luster is pearly to vitreous to dull.

Transparency crystals are transparent to

translucent.

Hardness is 3.5-4

Specific Gravity is 2.86 (average)

Streak is white.

Other Characteristics: Unlike calcite, effer-

vesces weakly with warm acid or when first powdered with cold HCl.

Associated Minerals: include calcite, sul-

fide ore minerals, fluorite, barite, quartz and oc-casionally with gold. Best Field Indicators are typical pink color, crystal habit, hardness, slow reaction to acid, density and luster.

Gypsum

Color is usually white, colorless or gray, but

can also be shades of red, brown and yellow.

Luster is vitreous to pearly especially on

cleavage surfaces.

Fracture is uneven but rarely seen.

Hardness is 2 and can be scratched by a

fingernail.

Specific Gravity is approximately 2.3+

(light)

Streak is white.

Associated Minerals are halite, calcite,

sulfur, pyrite, borax and many others.

Other Characteristics: thin crystals are

flexible but not elastic, meaning they can be bent but will not bend back on their own. Also some samples are fluorescent. Gypsum has a very low thermal conductivity (hence it's use in drywall as an insulating filler). A crystal of Gyp-sum will feel noticeably warmer than a like crys-tal of quartz. Best Field Indicators are crystal habit, flexible crystals, cleavage and hardness. Limestone (made up of the mineral Calcite)

Color is extremely variable but generally

white or colorless or with light shades of yellow, orange, blue, pink, red, brown, green, black and gray. Occasionally iridescent.

Luster is vitreous to resinous to dull in mas-

sive forms.

Transparency: Crystals are transparent to

translucent.

Cleavage is perfect in three directions,

forming rhombohedrons.

Fracture is conchoidal.

Hardness is 3 (only on the basal pinacoidal

faces, calcite has a hardness of less than 2.5 and can be scratched by a fingernail).

Specific Gravity is approximately 2.7

(average)

Streak is white.

Associated Minerals are numerous but

include these classic associations: Fluorite, quartz, barite, sphalerite, galena, celestite, sul-fur, gold, copper, emerald, apatite, biotite, zeo-lites, several metal sulfides, other carbonates and borates and many other minerals. Best Field Indicators are crystal habit, reac-tion to acid, abundance, hardness, double re-fraction and especially cleavage. http://mineral.galleries.com/minerals/hardness.htm

Glacial Till Chert

Texture is medium to fine.

Luster tends to be waxy.

Color ranges from white to gray, with lighter

68

Time Division

Began

___ Millions

of Years Ago

Typical events

within Indiana

Cenozoic Era

Quaternary

period 2

Glacial tills and outwash,

river sediments and soils,

Mastadons, Giant Beavers

and other ice age animals

Tertiary period 66 Scattered Gravels and sand

Mesozoic Era

Cretaceous

Period 144 No Sediments or fossils

Jurassic Period 208 No Sediments or fossils

Triassic Period 245 No Sediments or fossils

Paleozoic Era

Permian

Period 286 No deposits within Indiana

Pennsylvanian

Period 320

Great swamp forests; coal

stone, sand stone, and clay;

laid in repeated cycles

Mississippian

Period 360

Seas covered Indiana, lime-

stone, sandstone, shale and

gypsum deposited; blastoids

and crinoids common

Devonian

Period 408

Seas covered Indiana; lime-

stone, dolomite and shale

deposited; some Silurian

reefs continued to grow

Silurian

Period 438

Shallow seas over Indiana;

dolomite, limestone, and

shale deposited; Barrier,

patch and pinnacle reefs

began to form

Orovician

Period 505

Shallow seas; shale and

limestone deposited; bryozo-

ans and brachiopods com-

mon

Cambrian

Period 570

Shallow seas; sandstone and

dolomite deposited; no expo-

sure at surface only know

from drilling

Precambrian

Era 4600

Igneous, metamorphic

formed in very ancient

times; known only from

drilling.

values most common.

A wide variety of fossils will be present in-

cluding sponge spicules, brachiopods, bryozo-ans, corals, and crinoid columnals.

The Glacial Till Cherts will display a wide

variety of structural variations to include voids, druse, iron oxide lined voids, mineral inclusions in crystalline form, non-crystalline accretions, and oolites. Scientists believe that Glacial cobbles were commonly thermally altered. Heat treatment will produce orange, pink, and red tones in the matrix. Luster will be enhanced. http://virtual.parkland.edu/lstelle1/len/biface_guide/chert/documents/glacial_till.html

Shale Shale is a fine-grained sedimentary rock whose original constituents were clays or muds. It is characterized by thin laminae breaking with an irregular curving fracture, often splintery, and parallel to the often indistinguishable bedding planes.

The fine particles that compose shale can remain suspended in water long after the larger and denser particles of sand have de-posited out. Shales are typically deposited in very slow moving water and are often found in lake and lagoonal deposits, in river deltas, on floodplains, and offshore of beach sands. http://www.mywiseowl.com/articles/Shale

Background

69

Background

Rock Cycle Song (Sing to the tune of “Row, Row, Row Your Boat”)

SEDIMENTARY rock

Has been formed in layers

Often found near water sources

With fossils from decayers

Then there’s IGNEOUS rock

Here since Earth was born

Molten Lava, cooled and hardened

That is how it’s formed

These two types of rocks

Can also be transformed

With pressure, heat and chemicals

METAMORPHIC they’ll become.

Quick Rock Key

If the rock is an Igneous Rock: It may be colored.

It may have shiny flecks of mineral crystals in it that reflect light. The different colored minerals in the rock will be stuck together in no particular pattern.

If the rock is a Metamorphic Rock:

It may be many colored. It may have shiny flecks of mineral crystals that reflect light.

The different colored minerals in the rock will form a pattern of stripes, spots or swirls.

If the rock is a Sedimentary Rock: It will look as if it has layers.

It may have fossils in it.

70

Hard as a Rock

Chart Place your minerals

here, then move them

down the chart!

SMELL

FEEL

COLOR

STREAK

LUSTER

MAGNET

HARDNESS

WEIGHT

FIZZ

OTHER

1 2 3 4 5 6 7 8 9 10

Moh’s Scale of Hardness

2.5 or less

Fingernail

scratches

mineral

3.5 or less

Penny

scratches

mineral

5.5 or less

Nail

scratches

mineral

6.5 or less

Glass

scratches

mineral

Background

71

Rock ID Sheet Letter ____ Dolomite

√ May be many colors, but in Indiana is often brown or gray.

√ Feels slightly rough.

√ Composed mostly of tiny crystals of mineral dolomite which are visible with a magnifier.

√ A few bubbles, will form when acid is applied.

√ Hardness range of 3-5.5.

Letter ____ Sandstone

√ May be many colors, including brown, reddish brown, light pink, gray, or white.

√ Feels rough.

√ Composed of sand grains, which are mostly crystals of the mineral quartz, which are visible with the na-

ked eye.

√ Hardness range of 3 or greater.

Letter ____ Limestone

√ May be many colors, but typically is an off-white or shade of light brown or gray.

√ Depending on size of grains, may feel rough or smooth.

√ Generally contains fossil fragments, sometimes rounded and not easily identified, made of the mineral

calcite.

√ Bubbles vigorously in acid.

√ Hardness range of 3-5.5.

Letter ____ Chert

√ May be many colors, but in Indiana is most often a shade of brown, gray, or black, or has bands of those

colors.

√ Feels very smooth.

√ Composed mostly of microscopic crystals of the mineral quartz.

√ Forms sharp edges when broken.

√ Hardness range of 5.5 or more.

Letter ____ Shale

√ Mostly shades of gray, but sometimes black or a shade of red or green.

√ Feels very smooth and soapy.

√ Composed mostly of tiny crystals of quartz and clay minerals, visible only with a microscope.

√ Hardness range of 2.5 or less.

Letter ____ Gypsum

√ Mostly white in color.

√ Feels slightly rough.

√ Composed mostly of the mineral gypsum (crystals look like ice through magnifier).

√ Hardness range of 2.5 or less.

Background

72

Standards

simpler parts. 4.7.4 Use a variety of methods, such as words,

numbers, symbols, charts, graphs, tables, dia-grams, tools, and models to solve problems, justify arguments, and make conjectures.

4.7.5 Express solutions clearly and logically by us-ing the appropriate mathematical terms and notation. Support solutions with evidence in both verbal and symbolic work.

Science 4.2.4 Use numerical data to describe and compare

objects and events. 4.2.5 Write descriptions of investigations, using

observations and other evidence as support for explanations.

4.2.7 Identify better reasons for believing something than “Everybody knows that…” or “I just know” and discount such reasons when given by others.

4.3.5 Describe how waves, wind, water, and ice, such as glaciers, shape and reshape the Earth’s land surface by eroding of rock and soil in some areas and depositing them in other areas.

4.3.6 Recognize and describe that rock is composed of different combinations of minerals.

4.3.7 Explain that smaller rocks come from the breakage and weathering of bedrock and larger rocks and that soil is made partly from weathered rock, partly from plant remains, and also contains many living organisms.

Social Studies 4.1.1 Native American Indians and the Arrival of

Europeans to 1770. Identify and compare the major early cultures that existed in the region that became Indiana prior to contact with Eu-ropeans.

4.1.2 Native American Indians and the Arrival of Europeans to 1770. Identify and describe his-toric Native American Indian groups that lived in Indiana at the time of early European explo-ration, including ways these groups adapted to and interacted with the physical environment.

4.3.5 Physical Systems: Explain how glaciers shaped Indiana’s landscape and environment

4.4.1 Give examples of the kinds of goods and ser-vices* produced in Indiana in different histori-cal periods.

Grade 5 English/Language Arts

5.4.5 Use note-taking skills when completing re-search for writing.

5.7.1 Ask questions that seek information not al-ready discussed.

Grade 3 English/Language Arts 3.7.3 Answer questions completely and appropriate-

ly. 3.7.4 Identify the musical elements of literary lan-

guage, such as rhymes, repeated sounds, and instances of onomatopoeia (naming something by using a sound associated with it, such as hiss or buzz).

3.7.15 Follow three- and four-step oral directions.

Mathematics 3.5.1 Measure line segments to the nearest half-

inch. 3.6.5 Recognize the relative advantages of exact

and approximate solutions to problems and give answers to a specified degree of accura-cy.

Science 3.1.2 Participate in different types of guided scien-

tific investigations, such as observing objects and events and collecting specimens for anal-ysis.

3.1.3 Keep and report records of investigations and observations* using tools, such as journals, charts, graphs, and computers.

3.1.4 Discuss the results of investigations and con-sider the explanations of others.

3.1.5 Demonstrate the ability to work cooperatively while respecting the ideas of others and com-municating one’s own conclusions about find-ings.

Grade 4 English/Language Arts 4.7.1 Ask thoughtful questions and respond orally to

relevant questions with appropriate elabora-tion.

4.7.2 Summarize major ideas and supporting evi-dence presented in spoken presentations.

Mathematics 4.5.1 Measure length to the nearest quarter-inch,

eighth-inch, and millimeter. 4.5.2 Subtract units of length that may require re-

naming of feet to inches or meters to centime-ters.

4.6.1 Represent data on a number line and in ta-bles, including frequency tables.

4.6.2 Interpret data graphs to answer questions about a situation.

4.7.1 Analyze problems by identifying relationships, telling relevant from irrelevant information, se-quencing and prioritizing information, and ob-serving patterns.

4.7.2 Decide when and how to break a problem into

73

Standards

quadrants of the coordinate plane. 6.5.1 Select and apply appropriate standard units

and tools to measure length, area, volume, weight, time, temperature, and the size of an-gles.

6.7.1 Analyze problems by identifying relationships, telling relevant from irrelevant information, identifying missing information, sequencing and prioritizing information, and observing pat-terns.

6.7.3 Decide when and how to break a problem into simpler parts.

6.7.5 Express solutions clearly and logically by us-ing the appropriate mathematical terms and notation. Support solutions with evidence in both verbal and symbolic work.

Science

6.2.5 Organize information in simple tables and graphs and identify relationships they reveal. Use tables and graphs as examples of evidence for explanations when writing essays or writing about lab work, fieldwork, etc.

6.3.18 Investigate and describe that when a new material, such as concrete, is made by combining two or more minerals, it has properties that are different from the original materials.

5.7.2 Interpret a speaker’s verbal and nonverbal messages, purposes, and perspectives.

5.7.3 Make inferences or draw conclusions based on an oral report.

Mathematics 5.6.1 Explain which types of displays are appropri-

ate for various sets of data. 5.7.1 Analyze problems by identifying relationships,

telling relevant from irrelevant information, se-quencing and prioritizing information, and ob-serving patterns.

5.7.2 Decide when and how to break a problem into simpler parts.

5.7.4 Express solutions clearly and logically by us-ing the appropriate mathematical terms and notation. Support solutions with evidence in both verbal and symbolic work.

Science 5.3.8 Investigate , observe, and describe that

heating and cooling cause changes in the properties of materials, such as water turning into steam by boiling and water turning into ice by freezing. Notice that many kinds of changes occur faster at higher temperatures.

5.4.8 Observe and describe how fossils can be compared to one another and to living organisms according to their similarities and differences.

Social Studies 5.1.1 Give examples of early cultures and settle-

ments that existed in North America prior to contact with Europeans.

5.5.1 Describe basic needs that individuals have in order to survive — such as the need for food, water, shelter, and safety — and give exam-ples of how people in early America adapted* to meet basic needs.

Grade 6 English/Language Arts 6.4.5 Research Process and Technology: Use note-

taking skills when completing research for writ-ing.

6.7.3 Restate and carry out multiple-step oral in-structions and directions.

6.7.1 Relate the speaker’s verbal communication (such as word choice, pitch, feeling, and tone) to the nonverbal message (such as posture and gesture).

Math 6.1.6 Use models to represent ratios. 6.2.7 Understand proportions and use them to solve

problems. 6.3.7 Identify and graph ordered pairs in the four

74