4DB-01PO

4-HGeology Project

Collecting Rocks,Minerals & Fossils

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Written by William Fountain, Extension Specialist in Horticulture, with assistance from WendyStivers, Extension Program Specialist for 4-H/Youth Development, and Patricia P. Schrader,former Extension Information Specialist.

ContentsDid You Ever Think about Being a Rock Hound? ...................................................... 2Let’s Go Back in Time… WAY Back .................................................................................. 4Geologic Time Clock (Noon to midnight on the 4th day) ..................................... 5The Difference in Minerals and Rocks Is ELEMENT-ary ........................................... 7Fossils, the Senior Citizens of Plants and Animals! .................................................. 7 Thinking about Your Collection .................................................................................. 11Types of Rocks .................................................................................................................... 12Types of Minerals ............................................................................................................... 17Types of Fossils ................................................................................................................... 18Deciding What’s What… Rock Identification .......................................................... 19A Special Find… Crystals! ............................................................................................... 20Rocks That Glow in the Dark… Fluorescence and Phosphorescence ........... 22So You Want to Do More… Advanced Activities ................................................... 23Putting It All Together… Displaying Your Collection .......................................... 23Exciting Places to Visit in Kentucky ............................................................................. 25

Photographed by Bill Mesner, former Extension Information Specialist.

We wish to express sincere thanks to the Geology Department of the University of Kentucky forthe generous help in the development of this publication.

We appreciate the loan of valuable specimens from personal and museum collections forphotographing. To Dr. Lois J. Campbell, Dr. J. Gregory McHone, and Dr. Nicholas Rast, chairmanof the Department of Geology, we are very grateful.

We are especially indebted to Dr. McHone who spent many hours reviewing various drafts ofthis geology project and who was always available to answer questions and provide expertise.

We also appreciate the help of agents, parents, and other helpful persons who reviewed thematerial and offered useful suggestions.

Did You Ever Thinkabout Being a RockHound?

A what?? A rock hound. Peoplewho collect rocks often callthemselves “rock hounds.”

“But,” you may be thinking toyourself, “I’m not interested inrocks…too dull for me.”

Actually, the study of rocks(petrology), minerals (mineralogy),and fossils (paleontology) isfascinating and important.

Geology is the science thatteaches the history of the earth,especially as recorded in rocks.Cave dwellers first becameinterested in the differences in thetypes of rocks when theydiscovered that the rock we nowcall flint made better arrowheadsand tools than other types of rock.“O.K.,” you say, “I can’t argue withthat. But we don’t hunt our supperwith a flint arrowhead these days.Rocks just aren’t that important tous now.”

Wrong! Let’s look at this 4-Hpublication. It is made of paperheld together by steel (a metal)staples. It was written on acomputer that stored theinformation on a computer disk.The disk is made of plastic (frompetroleum found by geologists)and has iron oxide (iron is a metal)on it. Computer chips are made ofsilicon dioxide (the mineral quartz).

This booklet was printed on apress made of metal. Some inkshave metals or minerals in them tomake them last longer or to givethem unique colors. The bookletwas stored in a metal buildingbefore it was delivered to yourcounty. It was taken to your countyin a metal truck that burnedgasoline (a petroleum product) asit traveled over concrete (a rockproduct) and asphalt (a petroleumproduct) roads.

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You may need glasses to readthis publication. Glass, as with acomputer chip, is made of silicondioxide (quartz).

The light that helps you see thisbooklet uses electricity, made fromburning coal or oil. Or perhapsuranium (a metal) was used toproduce the electricity.

This list could go on and on. Youmight even want to see how far youcan extend it. Rocks, it seems, aremore important to us today thanthey were to the cave dwellers. Thisis why some people say we are stillliving in the “stone age.”

Collecting rocks can be fun andwill teach you about the history ofthe earth’s past as well as what ishappening today. Making acollection will help you becomefamiliar with the different types ofrocks and minerals that make upour planet. You don’t even have togo far from your home or school toget started.

Rocks are so common thatsometimes we often don’t evennotice them. The easiest places tolook for rocks are along streambanks and road cuts. Later, you maywant to take a field trip to otherlocations.

Kentucky has a large number ofdifferent types of rocks andminerals that will look beautiful inyour collection. After you havebeen collecting for a while, youmay decide to collect just one typeof rock, such as fossils, ores (rockfrom which we get gold, iron,copper, lead, and other metals), orminerals.

A road cut, such as that shown above, is a history book you can’t carry around with you.

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Got Your Attention?

O.K., now that we have yourattention, you may want to know alittle more about this “rock hound”project.

First, this is a 4-H project. Youdon’t have to be any special age totake geology, but it would bebetter to take this project after youhave completed Exploring NaturalResources. In that project, you learnabout all the systems that make upour environment. That project willmake geology even morefascinating!

When you take this geologyproject, you can design your ownplan. You (or your whole group)decide where you want to takefield trips to see rock and fossilcollections and who you want tospeak at your group meetings. Andyou decide what you want in yourcollection and which specimens toput in your box for exhibit.

When you get into the study ofgeology and the collecting ofrocks, you may want to do ageology project more than oneyear. Some people take geology forseveral years. You can plan yourown project by setting goals forwhat you want to accomplish eachyear. You may want to do a study ofthe formation or mining of coal inKentucky. Or you may want to do a

study on how continents wereformed, on the glacial stages onearth, or on earthquakes or faults.There is no limit to the interestingtopics of study you may choose.Then you can use these studies forgiving speeches anddemonstrations.

Remember: To enter yourcollection for state 4-Hcompetition, you must follow thespecifications in the state faircatalog. Your 4-H agent or leadercan tell you about the rules.

Ready to start? This is what you willlearn:• The difference in minerals,

fossils, and rocks.• The types of minerals.• The three main classes of rocks

and how to identify them.• How to clean your rocks and

display them in a collection.• The location of some good rock-

collecting sites in Kentucky.

You may also:• Take field trips.• Enter your exhibit in 4-H

competition.• Give a talk or demonstration on

your rock project.• Do advanced geology work.• Participate in leadership and

citizenship activities.

Let’s Go Back inTime… WAY Back

An Unusual Time Clock

Scientists tell us that the earthwas formed about 4½ to 5 billionyears ago. It is impossible for ourminds to fully grasp such a longperiod of time. You can get an ideaof just how long this is if you thinkof the earth as having been createdin the first instant of a four-dayperiod.

It was not until the verybeginning of the third day that themost simple forms of life appeared.At noon on the fourth day, the firstinvertebrates (animals having nobackbone) appeared. At 3 p.m., thefirst fish appeared in the oceans.Amphibians such as frogs andsalamanders appeared at 5 p.m.,and reptiles such as snakes, turtles,lizards and dinosaurs at 6 p.m.

The organic material that wouldform our fossil fuels (oil and coal)were formed between 6 and 10p.m. The first mammals did notevolve until 9 p.m. It was not until1¼ minutes before midnight at theend of the fourth day that humanbeings appeared (1 million yearsago). We entered the 20th century1/200 second before midnight, andthe first man walked on the moon(1969) just 1/1000 of a secondbefore midnight at the end of thefourth day!

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Creatio

n of t

he eart

h

End of 1

st day

End of 2

nd day

End of 3

rd d

ay

First i

nvertebra

tes

Oil,

gas,

and coal f

ormed

Din

osaurs e

xtinct

Present t

ime

This four-day time line represents the five billion years since the earth was created. The shaded portion on the far right is the period noon to midnight on the fourth day. This twelve-hour period has been expanded into the face of a clock shown below.

Geologic Time Clock(Noon to midnight on the 4th day)

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1

2

3

4

5

67

8

9

10

11

COAL,O

IL,A

ND

GA

SF

OR

ME

D

MA

MM

ALS

REPTILES

DIN

OSA

URS

REPTILES

AMPHIBIA

NS

FIS

HES

INVERTEBRATES

HUMANS

12 “hours” = 600 million years.Humans appeared 1¼ minutesbefore midnight.

Activity

If one hour on the geologicclock is equal to 50 millionyears, can you figure out whenColumbus discoveredAmerica? When theDeclaration of Independencewas written? At what pointyou were born?

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The Radiation Theory

How do scientists know how oldthe earth is? They don’t know forsure, but they do have a good wayof estimating the earth’s age—bymeasuring the radioactivity of therocks found on earth.

The radiation theory seems tobe quite accurate. Scientists knowhow much radiation an object suchas a rock had at its beginning onearth. They also know how muchand at what rate radioactivity islost. So, the radiation theorydivides the total radioactivity lossby the yearly loss, giving the age ofthe rock. It does not give the age ofthe earth, merely the age of therock tested.

If scientists could find the oldestrock, they would, in theory, be ableto tell the age of the earth. Theoldest rock to date was found inGreenland. It has been determinedto be 3.8 million years old.Geologists believe that even olderrocks once existed but have beenworn away.

You can see that each rock is likea history book that may be manymillions of years old. All you haveto do is know how to read thebook. The next time you are ridingon an interstate highway, noticethe change in colors and texturesof the layers of a road cut from topto bottom. You might be seeing theend result of flash floods and duststorms, warm shallow lakes andglaciers, lush tropical forests andswamps, earthquakes, landslides,meteor storms, and animalsgrazing peacefully in a field ofgrass. And different “pages” of thishistory book may be within a fewinches of each other.

The Geologic Time Scale

Geologic time is broken intothree “eras,” several suberas called“periods,” and several subperiodscalled “epochs.” The eras andperiods are shown in the chart atright. Each era, period, or epochrelates to certain occurrences thatwere happening on earth at acertain time, such as the time ofmajor glaciers, mountain building,etc.

Many of Kentucky’s coalfieldswere formed during theMississippian and Pennsylvanianperiods. And much of Kentucky’s“black shale” dates to the DevonianPeriod, while its limestone andfossils date to the OrdovicianPeriod.

If you are interested in thebreakdown of periods into epochs,you can find information in specificreference books on fossils andgeology or in encyclopedias.

You may also want to study thevarious forms of life that existed ineach era, especially if you areinterested in a fossil collection.

Road cuts such as this one provide an opportunity to see the different layers of weatheredmaterials that have been deposited over millions of years.

CENOZOIC ERA

Period Years Ago

Quaternary 1½ million

Tertiary 66 million

MESOZOIC ERA

Period Years Ago

Cretaceous 144 million

Jurassic 208 million

Triassic 245 million

PALEOZOIC ERA

Period Years Ago

Permian 286 million

Pennsylvanian 320 million

Mississippian 360 million

Devonian 408 million

Silurian 438 million

Ordovician 505 million

Cambrian 570 million

PRECAMBRIAN: More than 80 percent ofthe earth's estimated 4.5 to 5 billion yearsfalls within this era.

NOTE: This chart is based on scientificevidence and is sometimes revised. Sincethere were no human beings to record theancient information, revisions are made asnew measurements are made.

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The Difference inMinerals and Rocks IsELEMENT-ary

The earth we live on is a ball ofrock 7,927 miles in diameter. Itweighs 6.6 sextillion tons. Whilemost of our knowledge of the innerpart of the earth is limited to anarea about 15 miles deep, scientistsare developing new methods tostudy the earth at a greater depth.Nearly 98 percent of the earth’scrust is made up of eight knownelements: oxygen, silicon,aluminum, iron, calcium, sodium,potassium, and magnesium.

properties such as crystal shape,cleavage, color, streak (hardness),taste, smell, and feel. All mineralsare solid. (The word “mineral” isalso used outside of science toinclude coal, oil water, gas, andrelated resources; however, theseare not strictly minerals.)

There are about 60 types ofminerals found in our state.However, more than half of theseare not commonly found or arefound as small pieces mixed in withother minerals. Coal and oil areoften called “mineral resources,”but they are not really mineralsbecause they were once animalsand plants. They are organic, andminerals are inorganic.

Minerals are often found incrystal form. Crystals are usuallymade up of fairly pure material andmay look polished. They alwayshave smooth flat sides called“faces.” You have probably seenquartz, a mineral, that is long andhas six sides. Often, it comes to apoint. This is an example of acrystal.

Rocks

Rock is the solid mass thatmakes up much of the earth’s crust.Rocks, like minerals, have neverbeen alive. They are different fromminerals in that they are not pure(uniformly the same material).Rocks are made of a mixture ofminerals. Many times you can lookat a rock and see the differentminerals.

Granite is a good example of arock in which the different mineralsare visible. It is always made up ofquartz, mica, and feldspar but mayalso contain other minerals. In somerocks, different mineral pieces are sosmall that it is difficult to see them.You have probably seen polishedslabs of granite used as monumentsor as building materials.

molten interior

crust

Minerals

Minerals are made up of one ormore elements. Elements differaccording to the number of atomicparticles they contain. There are102 known natural elements onearth; only about 20 of them arefound in a pure, or natural, state.Minerals have never lived asanimals or plants; they areinorganic. They are relatively puresubstances that can be named by adefinite chemical formula.

Some examples of mineralsinclude salt, iron, sulfur, gold, andsilicon dioxide (white sand).Minerals have definite physical

Crystals always have smooth, flat sidescalled faces.

Fossils, the SeniorCitizens of Plants andAnimals!

Fossils are fascinating! Found inrocks, they offer a clue to the age ofthe rock and the kind of prehistoriclife found on earth. The older therock, the simpler the plant andanimal fossils it contains.

Fossils are any type of life formsthat have been preserved since thetime they lived—thousands ofyears ago. Today we know thatthese creatures lived where theirfossil remains are found. Manyanimals, such as clams, sea snails,and certain fish, live only in the sea.So, whenever fossils of this type arefound, we know that the sea oncecovered that area. It is notuncommon to find fossils of fishthat lived millions of years ago inthe mountains of Wyoming, morethan 1,000 miles from the sea.

Fossils are found in nearly everypart of Kentucky. Tusks, teeth, andother bones of prehistoric animalshave been found in the gravel pitsof northern Kentucky. These animalremains were deposited in the areaduring the glacial periods. Fossils ofmastodons have been found in theGreen River valley and in MagoffinCounty. Giant beaver fossils, as wellas tree and plant fossils, have beenfound in Eastern Kentucky.

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Fossils also tell us what theclimate was like thousands, or evenmillions, of years ago. If you find afossil of an ancient crocodile, youknow that the area where youfound it was once a swamp and theclimate was quite warm. We knowthis because crocodiles need thattype of environment to survive.

Did you know that coal seamshave been found in Antarctica?Coal is formed from ancient plantlife, which has been squeezed bytremendous pressure. This meansthat tropical plants once grewwhere now there is only ice andsnow.

Fossils also help in the search foroil. Geologists think that oil wasformed when small creatures,usually in the sea, died and fell tothe bottom, forming layers. Whenenough of these creatures piled up,the weight of the top layerssqueezed the oils from thosebelow. The oil then moved to rocksthat had spaces to hold it—muchlike a sponge holds water. Over aperiod of time, the oil ran together,forming the oil deposits of today.Coral deposits are examples of thisprocess. We look for coral inlimestone deposits as indicators ofoil traps.

Other fossils are used to indicatethe temperature and pressure ofrocks that allow oil to form. If it istoo hot, the oil will disintegrate; if itis too cool, the oil will not form.

There are several ways in whichanimals and plants can bepreserved into fossils:

Actual Preservation

Sometimes animals that hadhard shells or bones became fossilsbut did not turn to stone. Theyremained the same as they did inlife. This process is called “actualpreservation.” There are threemajor ways in which this canhappen: (1) freezing, (2) drying, and(3) in tar or peat bogs.

This fossil fern from the Pennsylvanian Period about 280 million years ago has beencleaned, dried, and shellacked to protect its surface.

This is the fossilized tooth of a mastodon, a large prehistoric elephant. Compare the size tothe human bicuspid in the righthand corner.

Freezing. Freezing is fairlyuncommon but it is the bestmethod of preservation. In Siberia,Russia, mammoths (prehistoricelephants) have been found

completely preserved, just likemeat in a freezer. The skin, hair, andtusks were preserved just as theywere in life. Some people haveeven eaten this meat!

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Drying. This is another type ofactual preservation. Some animals,in hot climates where there is littlemoisture, dried in the sun afterdeath. They have been preservedmuch like mummies.

Tar or peat bogs. The last type ofactual preservation occurred in taror peat bogs. Plant and animal lifeleft in these places sank to thebottom. They were surrounded bya thick, gooey substance that didnot allow the air to get in. Becausedecay bacteria cannot live in thisenvironment, no decay took place.

Permineralization

Don’t be afraid of this big word!It is just a term to describe anotherprocess by which fossils wereformed. Sometimes a plant oranimal died in an area where water,carrying dissolved minerals, soakedinto its surface. When the waterevaporated, the minerals were leftand then hardened. In most cases,this type of fossilization will behollow.

If the minerals soaked intocavities such as air pockets left inbones when the marrow decayed,the partially preserved remains alsohave been permineralized.

Replacement

Most petrified wood is anexample of replacement. In thisprocess, a tree died and wascovered by a landslide of earth,lava, or water. As it began to decay,a molecule of wood rotted and wasreplaced by a molecule of mineral.By this process, every grain andwood fiber was turned to stone andtoday can be seen just as it couldwhen it was wood.

Only a scientist with years ofexperience can tell what type ofwood it was. It is important toremember this when you findpetrified wood. Don’t confuse itscolor with the color of present-day

Non-decayedwood cellsDecayed wood

cells (hollow)

Different types ofminerals that havefilled hollow cells

wood. In Arizona, bright blue,yellow, and red petrified wood hasbeen found. Because wood doesnot grow in these colors, we knowthat the color of the fossil wascaused by the mineral thatreplaced the wood. If a greenmineral takes the place ofthe rotting wood, thepetrified wood will begreen. Most petrified woodis actually agate, which isused as a gemstone.

Carbonization

Coal is an example ofcarbonization. In thisprocess, the fossil is turnedto what is known as“carbon.” Plants die, fallinginto a swamp. More plantsdie and fall on top until,finally, the plants on thebottom are squeezed intowhat we know as coal.

Fossils tell us somethingof the early climate of anarea. Coral found in rocks asfar north as Greenland leadus to believe that theclimate at one time was

Plant life

Soil: formed fromlayer upon layerof dead plants

Coal: formed fromdead plants. Occasionally, plantfossils can still befound in coal seams.

Greatdownwardpressure

warm in that area. Fir and sprucetree fossils, normally found in coolclimates, have been found in thetropics. This would indicate that theweather there was cool at one time.

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Traces or Trace Fossils

The last type of fossilization isthe process that leaves “traces.”These are not the actual remains ofthe living parts of either plants oranimals but are traces left by them.This occurs when an animal orplant is trapped in mud that laterhardens, leaving a mold. Thisprocess is much like making a moldfor plaster. First you carve out ashape (mold) and then pour inplaster. You then have the cast ofplaster when it dries. What comesout of such a mold is sometimescalled a “concretion.”

An example would be footprintsleft by dinosaurs. In some parts ofthe country, footprints of thesecreatures, which walked the earth

This agate fossil is asection of a treestump. It wasfossilized throughthe “replacement”process in whichsilica in groundwater has replacedwood.

over 65 million years ago, haveturned to stone. These footprintsmay be almost as large as abathtub. Prints left by one of thesehuge animals were not actually apart of the animal when it was alivebut a trace of its travels.

Another example of a trace is a“gastrolith” (a stone found in thestomach). Have you ever seenchickens pecking and swallowinglittle stones? They do this becausethey have no teeth and cannotchew their food. To be able tobreak down their food, theyswallow sharp rocks to “chew” it forthem. Paleontologists (scientistswho work with fossils) have foundsome of these rounded stonesalong with the bones of dinosaurs.

Worm holes or feeding trailspreserved in ancient sea-floor mudare common trace fossils found inKentucky. These are sometimesfound in intricate spiral patterns.

There are fossils of many kinds ofanimals and plants no longer livingon earth. There were dragonflieswith two-foot wingspans, giganticelephants with long straggly hairand ferns the size of trees.

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Thinking about YourCollection

When you begin to collect rocks,minerals, or fossils, it is importantto remember that you are puttingtogether a collection of samples.You need not bring home thewhole mountain, just pieces of thedifferent types of rocks that makeup the mountain!

If a rock is bigger than your fist,trim it down or do not bring ithome. It is easier to display 15 rocksthe size of a walnut than 15 the sizeof a basketball! If all the samples areabout the same size, the collectionwill appear much neater. Some ofthe nicest looking collections arecalled “thumbnail” collections—where all of the samples are about acubic inch in size. (Do not, of course,trim spectacular, large mineralsamples or fossils; keep these as youfind them.)

Equipment You Will Need

You will need a pack or bag inwhich to carry your samples home.If you think there is a chance youwill be visiting several places orcollecting more than one type ofrock, it is a good idea to bring apencil and some index cards formaking notes. (You should writedown the date, where you foundthe rock, what type of rock youthink it might be, plants or otherrocks in the area, and any otherinformation that will be of help orinterest later. Also, number eachrock as you pick it up. Then placethe card with the rock and wrapthem both in newspaper.)

Other equipment you may wantto invest in are a geologist’s pick orbrickmason’s hammer for breakingrocks (a carpenter’s hammer is toobrittle), goggles to protect youreyes, a cold chisel for cutting rocks,and a pair of heavy gloves toprotect your hands.

You will also need comfortablewalking shoes, a magnifying glassfor examining rocks, a pocketknifeand, very importantly, a canteen ofwater and a snack.

Check off these items as youprepare for your field trip:• Bag• Index cards• Pencils• Newspapers• Geologist’s pick or brickmason’s

hammer• Goggles• Cold chisel• Heavy gloves• Comfortable walking shoes• Magnifying glass• Pocketknife• Canteen of water• Snack

Although brachiopods were one of the earliest forms of life, they still exist today. Clusters of fossils such as this are commonly found inlimestone. They are molds of the brachiopod shells.

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Some Rules of Collecting

Many of the places withinteresting rock formations are onprivate property. It is always

important to get permission

from the owner before going on

private property.

Mine dumps and quarries areexcellent places to collect rocks, butmost owners will require someoneto go with you for your own safety.You should never enter anabandoned mine without an adultalong who knows that the mine issafe. Many abandoned mines havepoisonous gases in them or may bein danger of caving in.

Very few people will object toyou collecting a few rocks from theirproperty. What they do not want issomeone who will leave litter, writeon rock walls, or damage trees orrare rock formations. After you arethrough collecting, it is a good ideato stop and thank the propertyowners and tell them what you sawand learned.

In addition to collecting yourown rocks, you may want to tradewith other collectors. Also, thereare a large number of rock shopsaround the country where you canbuy rocks. Make a habit of lookingfor these places in the telephonebook when you are out of townvisiting friends or relatives.

Cleaning Your Rocks

Once you have returned home,clean your rocks with warm waterand a soft brush. After they areclean, let them dry. Then look atyour samples again. Keep onlythose that will improve yourcollection, unless you plan to traderocks with someone else.

Place a spot of white enamelpaint about half the size of a dimeon the rock. The smaller the rock,the smaller the spot will have to be.After the paint is dry, write thenumber on the spot with a blackpen. Remember to number yourrocks according to the order in

which you find them. Be sure thissame number is on the card youwill keep in a file box. Recordeverything you know about thisspecimen on the card.

In addition to the date andwhere the rock was found, you maywant to record what types of plantswere growing in the area, the typeof rock, and its chemicalcomposition. Write this down; don’ttrust your memory.

Types of RocksWhoa! Hold it. By now you must

be thinking to yourself: “How can Iwrite down the type of rock and itschemical composition? I don’t evenknow them.”

Rocks are divided into threedifferent types: igneous,sedimentary, and metamorphic.What makes these three groupsdifferent is how they were formed.Most rock collections will bedivided into these three groups.

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Igneous

The interior of the earth is very,very hot—hot enough, in fact, tomelt rock—and melted rock is justwhat is down there. Sometimes thismelted rock works its way up to thesurface and forms a volcano. If itgets close to the water table, a hotspring or a geyser will occur. Howfast and where this rock cools andwhat it was made of determinewhat type of igneous rock forms.Rocks that cooled off below theearth’s surface are known as“intrusive”; rocks that reached theearth’s surface before they cooledoff are called “extrusive.”

Granite and basalt are igneousrocks that cooled slowly enough toform large crystals. Granite isusually light-colored, although itmay be pinkish red or black-spotted. Basalt is a fine-grained,dark rock. It is mined, crushed, andsold as “traprock,” which is used forrailroad beds. Obsidian, which isblack volcanic glass, cooled so fastthat it did not form crystals.Obsidian was highly prized by theAmerican Indians for makingarrowheads.

The lava that rose to the surfacealso cooled so fast that it did notform crystals. In rocks that do formcrystals, you can see how relativelyfast they cooled. The more slowlythe rock cooled, the larger andbetter defined the crystals.

Volcano

Lava flowcreates extrusiverock

Intrusiveigneous rock

Molten rock

Large areas of land in somewestern states are covered by lava.There is some evidence of volcanicactivity in far Western Kentucky,near Illinois, and possibly in ElliotCounty. The formation in ElliottCounty is similar in composition tothat which produced diamonds inSouth Africa. Over hundreds ofmillions of years, these rocks haveweathered so much that they areno longer recognized as lava.

Granite is an igneous rock that was formed by slow-moving melted rock working its wayup through the surface of the earth. It is called “intrusive” because it cooled off before itactually reached the earth’s surface.

Basalt, like granite, was melted rock, but it cooled rapidly as it flowed out onto the surfaceof the earth. It is “extrusive” rock. Black and “clinkerlike,“ basalt is used for railroad beds.

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Sedimentary

Once there was nothing onearth but igneous rocks. Then heat,cold, wind, water, and themovement within the earth slowlybegan to break some of these rocksinto smaller and smaller pieces.These bits of dust, sand, and smallrocks began to collect in low spotsand build up in deeper and deeperlayers. With time, pressure, andnatural cements, they were onceagain bound together assedimentary rock. This process isstill going on today.

There are many types ofsedimentary rocks found inKentucky. Some of these containfossils; this tells us that Kentuckywas once under a large, warm,shallow sea. Some sedimentaryrocks common in Kentucky:• Sandstone, made from sand• Shale, made from mud

Sandstone showing different layers

Shale

Conglomerate

• Conglomerate, pebbles inanother type of sedimentaryrock

• Limestone, which is made fromshells or calcium carbonate(lime) deposited in the sea.

Coal, oil, and gas are often foundin layers within sedimentary rocks.(All three of these are found inKentucky.) If you see a layer of shalewith a layer of coal on top, thenanother layer of shale, then a layerof sandstone, you can tell a lotabout what the area was likemillions of years ago. First therewas a muddy lake or sea thatformed the layer of shale. Thenplants, which would form the layerof coal, began to grow. Then thearea again became a muddy lake,forming a layer of shale. Finally, thewater became clear as the sandwas deposited, possibly along anancient seashore.

Simplified Classification of Igneous Rocks*Texture or grain size Light Colored. Principal minerals:

orthoclase feldspar, some biotite, oramphibole

Intermediate. Principal minerals:plagioclase and orthoclase feldspar, amphibole, biotite, pyroxene

Dark Colored.Plagioclasefeldspar, pyroxene, amphibole, olivine

With quartz No quartz With quartz No quartz

Very coarse-grained Pegmatite

Coarse- tomedium-grained

Granite SyenitePhonolite (1)

GranodioriteQuartz diorite

Diorite GabbroPyroxenite (pyroxeneonly)Peridotite

Fine-grained (2) Rhyolite Trachyte Dacite Andesite Basalt

Porous Pumice Pumice Scoria

Glassy Obsidian

Fragmental or broken Fine-grained; ash or tuffCoarse-grained; breccia or agglomerate

* You will not find igneous specimens on field trips in Kentucky. You may purchase them from rock shops.

Activity

Research volcanoes in the United States. Find pictures and articlesabout the last volcano to erupt in the United States. Find out whichstate has volcanoes that erupt frequently.

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Activity

1. Look at a piece of coal. Canyou see its layers?

2. Do a little research andfind out what processestook place inside the earththat caused the formationof Mammoth Cave.

This “banded” sandstone, a sedimentary rock, is similar to those found near Somerset,Kentucky. The bands show clearly the tightly cemented layers of sediment that form thesolid rock.

Did You Know?

• That the presence of largedeposits of limestone near thesurface is one of the majorreasons that Kentuckydeveloped a large horseindustry? It was thought thathorses would have strongerbones due to the calcium in thewater.

• That the same conditions thatproduced coal were alsocapable of producing diamonds,which are pure carbon changedto crystals under great heat andpressure? Although geologistshave never found any, somepeople think there may bediamonds in Elliott and Morgancounties.

• What a “salt lick” is? Millions ofyears ago as the warm shallowseas that covered Kentuckydried up, the salt was left behindas a deposit. Much laterunderground streams workedtheir way through thesedeposits, picking up smallamounts of salt in the process.When this water came to thesurface as springs, it was slightlysalty. These places becameknown as “licks” becauseanimals would travel longdistances to them for the salt.Early settlers boiled the waterdown for the salty deposit andused it to preserve meat.

Simplified Classification of Sedimentary RocksTexture or Grain Size Chief Mineral Cement (matrix) Rock Name

1/16 inch or greater in agroundmass of 1/16 inch

Fragments can be any mineral or rock type

Silica, calcite, clay,iron oxide, etc.

Breccia (angular fragments) Conglomerate (rounded fragments)

1/16 inch or less Quartz Silica, calcite, iron oxide, etc. Sandstone

Calcite Calcite Limestone

Dolomite Dolomite Dolomite

Dense (cannot beseen with naked eye)

Gypsum Gypsum Gypsum

Clay Clay Shale

Quartz or silica Quartz or silica Chert

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Metamorphic

Metamorphic means “changedform.” If sedimentary or igneousrocks are exposed to heat andpressure, they will becomemetamorphic— a different type ofrock. If there is enough heat to meltthe rock, it will again become anigneous rock.

Metamorphic rocks sometimeskeep the layers or banding thatthey had as sedimentary rocks.Igneous rocks will not. Sometimesthese layers are very wavy due tothe extreme pressure that was puton the rock. Some metamorphicrocks are slate (made from shale),quartzite (made from sandstone)and marble (made from limestone).There are no metamorphic rocks inKentucky.

The geology of the earth isalways changing. New rocks are notbeing made, but many of the oldones are being changed from onetype to another. As you are outcollecting rocks, watch forindications that rocks are beingbroken down.

All of our soil was once rock.Plants growing in soil make weakacids that will break down rocks

Activity

Do a little research and findout what natural eventoccurred in 1811 and 1812that resulted in the formationof Reelfoot Lake. When theground sank, where did it go?What changes in pressure andtemperature occurred in therocks below the surface?Could there also have beensome folding in the rockformations?

Pyrite is a yellow metallic mineral sometimes called “fool’s gold.” It is an example of ametamorphic rock mineral. Pyrite is a common source of sulfur.

even more. A seed may fall into acrack in a rock. As the plant grows,the stem gets larger, causing thecrack to get larger, producingparticles of sand and dust.

You will often see a sandy arealeft at the bottom of a cliff as aresult of wind and water erosion.This sand may be washed into astream and, after a while, into theocean where, after several millionyears, it will become sandstone.

Simplified Classification of Metamorphic Rocks*Texture or Grain Size Principal Mineral(s) Rock Name Original Rock Type

Equigranular (equal grain size) Quartz Quartzite Sandstone

Equigranular to foliated Calcite and/or dolomite Marble Limestone and/or dolomite

Broadly foliated (parallel layers or bands) Feldspar, mica, amphibole,quartz, garnet, etc.

Gneiss Granite, rhyolite, shale, etc.

Thinly foliated Feldspar, mica, amphibole,quartz, etc.

Schist Andesite, basalt, rhyolite, shale, etc.

Very thinly foliated Mica, quartz, clay, (theseminerals normally cannot be seen with the naked eye)

Slate (1) Shale

* You will not find metamorphic rocks on field trips in Kentucky. You may purchase them from rock shops.

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Types of MineralsThere are more than 1,100

different types of minerals on theearth. Some minerals are verycommon and others are very rare,but all of them can be put into oneof the three groups: metallic

minerals, nonmetallic minerals,

and rock-forming minerals.

Metallic Minerals

Metallic minerals or metals arethe ones we use most often. Someof the common ones contain silver,copper, mercury, iron, nickel, lead,and zinc. Most of the metals arefound, along with other things, inrocks called ores. Ores were oftenformed into thin sheets, called veins,that ran through other rocks. Oftenthe veins were formed when watercarrying dissolved minerals seepedinto cracks and, over thousands ofyears, were slowly deposited untilthe crack was completely filled. Atother times, the veins resulted whenhot, gaseous materials seeped intocracks and hardened into veins asthey cooled.

into thin sheets); and most are shinywhen their surface is smooth.

Some metals can be mixedtogether to make a new metal, whichis harder than either of the puremetals. For example, bronze—amixture of copper and tin—is harderthan either pure copper or pure tin.

The study of these and otherfacts about metals is calledmetallurgy.

Nonmetallic Minerals

Nonmetallic minerals containother important materials such assulfur, graphite (the lead in pencils),gypsum, salt, borax, talc, asbestos,and quartz. These materials areimportant as building materialsand in the chemical industry. Sulfuris used as a drug, and salt isimportant in our diet. Glass is madefrom quartz, borax is used incleaning products, and talc is usedas powder.

Most industries could notoperate without nonmetallicminerals of some sort.

Native copper usuallycrystallizes into amore twisted,wirelike mass thanthis piece. Thisspecimen has beenpartially polished tomake an attractivepaperweight. Copperis a metallic mineral.

Native Copper

Asbestos

Quartz Sulfur

Every metal has a differentmelting point and a differentspecific gravity. (See p. 19 for moreinformation on specific gravity.)When ore is heated slowly to veryhigh temperatures, the differentminerals it contains will begin tomelt out at different times. Mineralsthat have a lower specific gravitywill float on the heavier minerals.

Metals are unique. They willconduct electricity; they are ductile(can be drawn out into a wire); theyare malleable (can be hammered

Rock-Forming Minerals

Rock-forming minerals are saidto be the building materials of theearth. They form our mountains,valleys, and soils. Most of theseminerals contain silicon andoxygen. The micas are in this group.Another rock-forming mineral isthe calcite group, which includeslimestone, marble, and chalk.Building materials such as concreteare made with crushed limestone.

It does not take long to see howimportant rocks and minerals are toour existence. You can also see howmany different jobs are related tothe study of rocks and minerals.Even if you do not choose to makegeology or one of the relatedstudies your lifelong work, thisproject can help you develop avery enjoyable hobby and at thesame time have fun in 4-H.

18

Types of FossilsFossils have a greater interest for

the general public than any otherpart of geology. Perhaps it isbecause of our natural curiosityabout the past. Fossils are theremains of prehistoric plant andanimal life on earth. They are alsoevidence that this life once existed.Fossils, like rocks and minerals, aredivided into different groups.

Most fossils are the result of hardparts of a living thing, such asbone, shell, or wood, that were leftbehind when the living creaturedied. It is only in very rare casesthat an entire animal has beenpreserved. The hard parts are oftenfound in an almost originalcondition. In other cases, theindividual cells have been replacedby dissolved minerals.

The soft parts, such as skin,leaves, and insects, are rarelyfound intact. Most of the fossil

Activity

Geology identification

contests are fun and will helpyou learn the common rocks andminerals of Kentucky andimportant rocks and mineralsfrom other areas. Contests canbe done in different ways:between individuals, betweentwo different teams in your club,or between clubs. Contests onother geology subjects are justas much fun. So choose sidesand look at the suggestedscoring method:

Clam

Coral

Placoderm

Fern

Trilobite

Brachiopod

Crinoid

Mosasaur Tooth

CephalopodShark Tooth

Cephalopod

5 points: correct name and classor groupName: BasaltClass: Igneous

3 points: correct name onlyName: BasaltClass: ??

2 points: correct class or grouponlyName: ??Class: Igneous

1 point off: each misspelled wordName: BesaltClass: Ineous (-2 points)

0 points: incorrect names orthose that are left blank or can’t bereadName: ??Class: ??

Common Fossils

19

records we have of thesespecimens are in the form ofmolds and casts where the partwas pressed into soft mud or sand.

Molds and casts are also the waywe find the most evidence that acertain type of life existed.Examples include the tracks ofanimals and borings of mollusks(shellfish) and worms. There areeven examples of petrified woodand shells with borings. You mightsay that these are fossils within afossil. Other examples of evidenceinclude fossil excreta andgastroliths, smooth roundedpebbles that aided the digestiveprocess of dinosaurs.

Deciding What’sWhat… RockIdentification

The task of identifying a rock youhave collected can be made mucheasier if you follow a few simplesteps.

The first decision to be made iswhether the rock is igneous,sedimentary, or metamorphic. Agood clue can be found at thecollection site by looking at nearbyrocks you can already identify.Another big help will be your 4-Hleader and friends who also collectrocks.

Always consult a good referencebook (found at any good bookstore)if you are not sure about aparticular rock. It will tell you howyour specimen should react to thefollowing tests.

Color

The color of a rock is one of thebest ways to tell what type it is.Since weathering will sometimeschange the color of the surface,you should make sure there is afresh surface to examine.

Sometimes a rock will havedifferent colors if there are differentminerals mixed with it. What youreyes tell you about a rock is calledfield identification.

Hardness

Each rock or mineral has acertain hardness that is unique tothat particular type. Each mineralwill scratch a softer mineral and, inturn, will be scratched by a hardermineral. For example, gypsum willscratch talc, and calcite will scratchgypsum, but talc will scratchneither gypsum nor calcite.(Because weathering will affect thehardness of a mineral, it is importantto make the test on a fresh surface.)

There is a list of commonminerals, called Mohs scale, thatarranges minerals in order of theirhardness. Having this scale willhelp you in identifying minerals bydetermining their hardness.

1. Talc (SOFTEST)2. Gypsum3. Calcite4. Fluorite5. Apatite6. Orthoclase7. Quartz8. Topaz9. Corundum10. Diamond (HARDEST)

You are not likely to find any rocksor minerals in Kentucky with ahardness greater than 7. Thefollowing list has some commonobjects that will help you decidethe hardness of your specimen. Forexample, if you can scratch thespecimen with a penny but notyour fingernail, the hardness of thespecimen will be between 2½ and3½. You can look up the hardnessof rocks and minerals in some ofthe reference books listed in thispublication.

FINGERNAIL .................up to 2.5PENNY ........................... 2.5 to 3.5KNIFE BLADE ................up to 5.5WINDOW GLASS ................... 5.5STEEL FILE .....................up to 7.0

Streak

The streak of a mineral can alsobe a valuable clue to its identity.The streak is the color of thepowder that is left when themineral is rubbed across anunglazed porcelain plate. (The backof an old piece of bathroom tilemakes an excellent streak plate.)

The color of a mineral may vary,but the color of the streak isgenerally constant. The streak maybe the same color as the mineral, orit may be entirely different. This isespecially useful for minerals thatlook metallic. The streak of whitemineral is always white.

A good reference book can helpyou identify minerals by theirstreak colors.

Specific Gravity

The specific gravity of a mineralis another test that can help youidentify an unknown specimen.Specific gravity is the comparisonof the weight of the specimen tothe weight of an equal volume ofwater. If a mineral has a specificgravity of 1, it has the same weightas water. A rock has a higherspecific gravity than a piece ofwood of the same volume. This iswhy the wood (less than 1) floatsand the rock (greater than 1) sinksin water. Likewise, different rocks ofthe same volume will havedifferent weights.

Finding specific gravity is easy todo if you can weigh the rock whileit is suspended in water and againwhile it is out in the air. (Thechemistry teacher at your local high

20

school may have a scale similar tothe one in the diagram.) Specificgravity is figured by the followingformula.

EXAMPLE: If the dry weight of a rock is 18.7 grams and the weight in water is 15 grams, use the following formula:

air weightair weight - weight in water

18.718.7 - 15

= 18.73.7

= 5.05 specificgravity

Acid Test

There are several ways to testrocks for acidity. One easy test is toput a couple of drops of vinegar ona piece of limestone. Notice that therock begins to bubble and hiss. Thisweak acid is reacting with thecalcium carbonite (CaCO3) to formcalcium chloride (CaCI2), water(H2O), and carbon dioxide (CO2). Ifyou put vinegar on a piece of pyrite(fool’s gold), it will release a gas thatsmells like rotten eggs calledhydrogen sulfide (H2S). Most otherminerals will not show these effects.

Magnetism

A few minerals, such asmagnetite (lodestone) andmeteorites, will attract iron ornickel. These magnetic minerals arerare in Kentucky. If you find a rockthat has this property, you mayhave found a meteorite or afurnace product. Furnace products,sometimes called slag, are what isleft over after a metal, such as iron,has been extracted from an ore.Slag is often used as gravel onrailroad lines.

A Special Find…Crystals!

When you begin to collect rocksit probably will not be long beforeyou find your first crystal. Crystalsare special!

Minerals that form crystals willalways form the same type ofcrystal. Two crystals of the samemineral may be of different sizes,but both will have the samenumber of sides and the samenumber of degrees in the sameangles. By deciding the shape ofthe crystal, you can narrow thepossibilities of its identity.

Galena is a silver-graymetallic mineral andan important lead ore.It is formed of heavy,brittle masses of cubiccrystals. It has ahardness of a 2.5 anda specific gravity of7.3 to 7.6.

Cleavage

Many minerals will split or breakalong certain definite lines orplanes of weakness. These weakerareas are closely related to theinternal structure of the mineraland are often parallel to the faces(surfaces) of a crystal. This splittingis called cleavage.

Minerals may have one, two,three, four, or six directions ofcleavage. The direction and howperfectly it splits depends on thecharacteristic of the particularmineral. Minerals that break easilyalong planes of weakness will havea shiny surface where the breakoccurs. Cleavage is importantinformation in identifying minerals.

Since calcite is easily found inKentucky, it would be a goodmineral for experimentation.

Activity

Check out your salt and sugar!Lay two crystals of salt andtwo of sugar on a piece ofplain paper. Examine theircrystalline shapes with amagnifying glass. What istheir shape?

21

The most perfect crystals will bethe smaller ones, so you may wantto purchase a small magnifyingglass to see them better. You maynotice that crystals sometimesbreak up light into the differentcolors of the rainbow.

Isometric Crystals—Equal Measure

Study the following illustrationsof various cubic forms with mineralexamples.

Cube

(six equal area faces)EXAMPLE: Halite (table salt)

Cube with octahedral modification

(small corner cut off cube)EXAMPLE: Sylvite

Cube with octahedral modification

(14 faces; most ofcorners cut off cube)EXAMPLE: Copper

Cube with octahedral modification

(14 faces; most ofthe corners cut off cube)

EXAMPLE: Copper

This calcite has “dogtooth” or flat hexagonal crystals with excellent cleavage. Calcite maybe colorless or white, but its impurities show yellow, orange, brown, or green. Calcite isfound in limestone where large crystals may form in veins or voids.

This fluorite crystal is the same rock as the calcite crystal shown above but turned over tothe other side. Fluorite is calcium fluorite, while calcite is calcium carbonate. Each mayform in the same carbonate (limestone) rock within cavities or veins. Both are nonmetallic.Fluorite occurs as clear cubes with purple or other colors. This specimen is pale yellowish.

Ferric iron caused the hues of purple and violet in this transparent quartz crystal calledamethyst. Amethyst is found in quartz geodes and is a nonmetallic mineral.

22

Octahedron

(8 faces; all corners cut off cube)EXAMPLE: Fluorite

Trapezohedron

(24 faces, each with 4 sides)EXAMPLE: Analcite

Rocks That Glow inthe Dark…Fluorescence andPhosphorescence

Some rock collectors collectspecimens which “fluoresce” or“phosphoresce.” When an invisibleultraviolet light (sometimes called ablack light) is shined on certaintypes of rocks, the light rays will bechanged to colors that can be seen.Minerals that do this are said to be“fluorescent.”

The beautiful, vivid colors areoften very different from thenatural color of the rock. If thespecimen continues to glow for awhile after the ultraviolet light hasbeen removed, the specimen issaid to be “phosphorescent” (likethe luminous dial on a watch).

Fluorescence is not verycommon, but phosphorescence iseven rarer. Some locations likeFranklin, New Jersey, are wellknown for their fluorescentminerals.

Uranium materials fluoresce, asdo tungsten and some zinc oresand minerals. Some minerals mayfluoresce because of impurities.Other minerals will fluoresce fromone location but not from another.Because of their beauty, the searchfor fluorescent minerals is exciting,but serious study is difficult andyou may have to work at night.

Portable quartz lamps thatproduce ultraviolet light can bepurchased from geology supplycatalogs or from rock shops. Usecaution with black light. Do notstare directly at the light source.

Hexagonal Crystals—Six Sides

Study the following illustrationsof various hexagonal forms withmineral examples.

Prism

EXAMPLE: Apatite

Flat Hexagonal Prism

EXAMPLE: Nepheline

Hexagonal Pyramid

(one pyramid)EXAMPLE: Zincite

Hexagonal Bipyramid

(2 pyramids)EXAMPLE: Quartz

Hexagonal Scalenohedron

(unequal sides)EXAMPLE: Siderite

Isometric crystals (continued)

23

So You Want to DoMore… AdvancedActivities

Try Lapidary Work

A lapidary is someone who cuts,polishes, or engraves preciousstones. It can take years of work tobecome an excellent gem cutter.Not all rocks and minerals aresuitable for cutting or polishing. Ifyou are interested in this activityand are not able to find suitablematerial to work with, you canpurchase rough material or partlyworked “blanks” from rock shops.

The equipment needed isrelatively simple and not tooexpensive. Cutting a hard materialsuch as agate requires a diamondwheel powered by an electricmotor. Because of the speed of theblade and the danger of flyingchips, this is a dangerous piece ofequipment and should beoperated only by someone withexperience. It is easiest to learn askill by working and studying withan experienced person.

Polish Your Stones

If you are interested in lapidarywork, you will need a tumbler forpolishing stones (rocks andminerals). There are many typesavailable for purchase from rockand mineral shops, or you canmake one from an electric motor,some pulleys, lumber, and otherspare parts. Check reference booksin your library, bookstore, orhobby shop.

A bucket piled to the top withrocks is not a good way to display acollection. Each specimen shouldbe displayed so it can be seen andcompared to others. A bookshelf isfine unless you plan to enter yourcollection in 4-H competition. Forthis, you will need a box that isrelatively large but shallow. Tobuild your own display box, contactthe industrial arts teacher at yourschool, the State 4-H Office, or your4-H agent or leader for help.

Boxes for the state fair should bebetween 16” x 22” x 3½” and 20” x24” x 3½”. Place the rocks so thatthe sides of the box are the 16” (to20”) dimension and the front andback of the box are the 22” (to 24”)dimension. Use a plexiglass coverthat can be easily removed forjudging. If you use hinges, placethem on the side or make them fitflush so that the box will be level.

If you use a fabric liner, such asfelt or velveteen, glue it in the boxwith fabric glue (available fromany store that sells sewing items).Since the purpose of the box is tomake the display easy to move,

The geology box you build or purchase should look like this one. Notice the grooves cut forinserting a plexiglass top. Also note the edge that is nailed on after your collection iscomplete and the plexiglass is in place.

the rocks must be glued firmly tothe bottom of the box. Allow theglue to dry at least 24 hoursbefore testing its hold.

Preparing Your Rocksfor Exhibit

O.K., you rock hounds,remember this! When you mountyour rocks for exhibit, you will haveto renumber them. That is, you willnot use the field number youplaced on the rock when you foundit. Follow this procedure:1. Decide which rocks from your

collection you want to exhibit.Set these aside from the rest ofyour collection.

2. Pull the field identification cardsfor these rocks from your file.

3. Decide how you want to placeyour rocks in the box. Place theheaviest rocks at the bottom ofthe box. (Remember, your boxwill be tilted up for display.)Whenever possible, groupspecimens by types. Forexample, place igneous rockstogether, sedimentary together,

Putting It All Together…Displaying Your Collection

24

3"

22" to 24"

16" t

o 20"

3"

3/4"

1/4" groove forsliding glass

1/4"

1/2"

1/4" plywoodnailed or stapledand glued

Section through

side of box

Alternate method

of construction 1/4"

3/8"3/4"

1/2"

3/8"

3/8"

3-1/4"

glass

1/4" plywood

crystal rocks together, andmetamorphic together. This maynot always be possible since youwill be placing the heavier rocksat the bottom. Decide exactlyhow you want to place thembefore you start to glue them in.

4. When you have decided theorder in which to exhibit yourrocks, you need to renumber therocks so they will be in the boxin numerical order. This isimportant, so read these

instructions very carefully. Paintover the field identificationnumber with white enamel;allow the paint to dry. Thenrenumber the rocks numericallyas they will be placed in the box.The smallest rocks will have thelowest numbers because theywill be nearest the top of thebox.

5. Next, prepare the geologyidentification label for each

specimen in your collection. Youcan get labels from your 4-Hagent or leader. Place a numberon the label to match the one onthe specimen. Then fill out therest of the information from yourfield identification card. In thespace for “Where,” give theorigin of the rock. Tell where therock was found, not where it waspurchased. If you buy at a shop,the owner can tell you the originof the rock.

6. Next, be sure to update yourfield identification card. Writethe exhibit number of the rockon the card. This way you cankeep your field identificationcard with all the correctinformation about when andwhere you found the rock in thefile even though the rock nolonger has the fieldidentification number.

DON’T FORGET to talk to your 4-Hagent about the different types andsizes of collections that will beaccepted at your county fair or theKentucky State Fair.

25

Exciting Places toVisit in Kentucky

State and national parks aregreat for viewing rock formationsand finding interesting rocks, butyou cannot collect rocks in theseparks without written permissionfrom the park ranger orsuperintendent. Because rockcollecting is generally not allowedat these parks, they are goodplaces for you to travel to see rockformations that have beendisturbed very little.

Natural Bridge State Park and

Red River Gorge are excellentplaces to see natural sandstonebridges. There are many fossils,including coral, along the RedRiver. There are also a couple ofsites in the gorge that show layersof sediment deposited when thearea was under water.

Mammoth Cave National Park

is the largest cave system in theworld. You can see limestone andmany calcium minerals.

Cumberland Falls State Park

has a large waterfall, an excellentexample of the sharp drop in theelevation of a river that causes awaterfall. There also has to be aharder layer of rock in the riverbedalong the upper part of the river.Water is one of the strongest forcesin nature that breaks down rocksand moves soil from one locationto another.

The Kentucky River offers anamazing view back in history wherethe river has cut a deep channelthrough the rock. Raven Run, anature sanctuary outsideLexington, has an excellentoverlook of the Kentucky RiverPalisades. It is along the KentuckyRiver between Frankfort andBoonesboro that you will find theoldest rocks in the state. Some areas old as 450 million years—formedlong before the dinosaurs roamedthe earth! You will find similar viewsof history in other rivers, streams,and creeks.

Road cuts offer a more limitedview of the rock layers, but theserocks are less weathered than thosealong riverbanks. The mostcommon rocks found in road cutsare sandstone, siltstone, shale, coal,and limestone. Kentucky has manyexcellent road cuts all over thestate, including Highway 119 inLetcher County where extensiveroad cuts expose different strata.

The Outer Bluegrass is knownfor its large deposits of fossil shells,corals, and other animals that livedhere when warm shallow seascovered this area 430 million yearsago. They are best preserved inlimestone. Many towns took theirnames from rocks and minerals ofthe surrounding areas. Maysvillewas once called Limestone.

Glacial deposits are not toocommon, but there are a few in thearea just south of Cincinnati.However, it was the Ohio River thatcarried away much of the silt andmelted ice. Occasionally, ice floesblocked the Licking, Kentucky, andSalt rivers, causing local floodingand lake-bottom sediments insome areas.

The Falls of the Ohio River atLouisville has been declared anature sanctuary, and while youcannot collect there, you may beable to see some fossil coral.

Greenup and Estill counties

once had a small iron industry. Theearly settlers used coal, limestone,and a low-grade iron ore to makethe iron that they needed. Therewas also some ironmaking in theLand Between the Lakes region inWestern Kentucky. At one timeKentucky was the third largest iron-producing state.

Big Bone Lick State Park isunique because of its salt-sulfursprings and deposits of fossilbones. This was the first collectingarea for fossil bones in NorthAmerica.

This 4-H geology collection is a good example of a project to enter for competition.

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See Rocks and Minerals in Kentucky Museums

• Audubon State Park ............................................................................................... Henderson• Berea College Department of Geology ..................................................................... Berea• Bernheim Forest ......................................................................................................... Clermont• Cumberland College Department of Geography ................................. Williamsburg• Eastern Kentucky University Department of Geology ............................... Richmond• Georgetown College Department of Chemistry ..................................... Georgetown• Kentucky Historical Society—Old Capitol Building ..................................... Frankfort• Louisville Museum of Science and Industry .................................................... Louisville• Mammoth Cave National Park ............................................................. Edmonson County• Morehead State University College of Science

and Mathematics ....................................................................................................... Morehead• Murray State University Department of Chemistry and Geology .............. Murray• Transylvania University Department of Geography ................................... Lexington• Union College Department of Chemistry ................................................... Barbourville• University of Kentucky Department of Geology—

Bowman Hall ............................................................................................................... Lexington• University of Kentucky Geological Survey—

Mineral Industries Building ................................................................................... Lexington• University of Louisville Department of Geology ............................................ Louisville• Western Kentucky University Department of Geology .................... Bowling Green

Plough, Frederick H. Field Guide toRocks and Minerals. Boston:Houghton Mifflin Company, 1976.

Shaffer, P.R. and H.S. Zim. Fossils.New York: The Golden Press, 1962.

Shaffer, P.R. and H.S. Zim. Rocks andMinerals: A Guide to FamiliarMinerals, Gems, Ores, and Rocks.New York: Simon and Schuster,1957.

Spock, Leslie E. Guide to the Study ofRocks. New York: Harper’s, 1953.

Ideas for Demonstrations& Speeches

• The differences between rocks,minerals and fossils.

• The tools and equipmentnecessary to begin collectingrocks.

• How to clean, identify, andmount rocks for a collection.

• How fossils are preserved.• Explain how coal is formed and/

or mined.• The glacial period on earth.• How Mammoth Cave was formed.• How we use rocks in our homes

(or business or town, etc.).• Come up with some neat ideas

of your own! (You may wanthelp from your leader.)

Citizenship & LeadershipActivities

• Serve as a junior leader for ayounger group of 4-H’ers who areinterested in a geology project.

• Help with a field trip for youngergeology project group membersto museums and othersuggested places.

• Practice good citizenship ruleswhen collecting rocks on privateproperty or visiting state andnational parks.

• Report interesting geologicalexperiences or observations toyour 4-H geology project groupor club.

• Take your club to a state ornational park to help with aclean-up operation. (Have yourleader make arrangements first.)

More Help Is Available…

If you are interested in specificinformation about the geology ofKentucky, the Kentucky GeologicalSurvey may have just what youneed. The Kentucky GeologicalSurvey is a research and servicedepartment at the University ofKentucky. It shares with theuniversity more than a century ofservices to the commonwealth.

This office does research on thegeology of Kentucky and itsmineral resources and provides theresults to the public. It alsocooperates with the U.S. GeologicalSurvey on two other statewideprograms: the investigation ofwater resources and the continuingrevision of topographic mapping.In addition, it cooperates with theUnited States Bureau of Mines.

In addition to the publicationsavailable to the public, the KentuckyGeological Survey has an extensivefile of materials. These includegeological maps of each “quadrangle”in Kentucky, county maps, topo-graphic maps, maps of most of thewells in Kentucky, and a number ofunpublished maps and reports. It will

help you purchase a geologic map ofyour home county to have as areference. The files may be inspectedat the Survey office from 8 a.m. tonoon and 1 p.m to 4:30 p.m. Mondaythrough Friday. The office is closedduring the noon hour.

Publications may be ordered from:

Kentucky Geological Survey

311 Breckinridge HallUniversity of KentuckyLexington, KY 40506-0056Phone: (859) 257-3896

Suggested GeneralReferences

The Geologic Story of Kentucky:Kentucky Geological Survey, ser.2, 8, Special Publications 9,University of Kentucky, 311Breckinridge Hall, Lexington,Kentucky 40546-0056.

Geology Golden Guides. Racine,Wisconsin: Western PublishingCompany, Department M, 1220Mound Avenue, 53404.

Loomis, Frederick B. Field Guide toCommon Rocks and Minerals.New York: G.P. Putnam andSons, 1948.

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4-H Geology Project Record

Name ____________________________________________ Birth Date _____________________________________

Address _________________________________________________________________________________________ Street & Number/Rural Route Town Zip

School ______________________________________________ Grade _____ County ________________________

Number of Years in 4-H __________ Number of Years in Geology __________

1. Describe your main objective or goal (s) for this project. _________________________________________________

_________________________________________________________________________________________________________

_________________________________________________________________________________________________________

_________________________________________________________________________________________________________

2. Were you successful in reaching your goal (s)? Yes _____ No _____

If no, why? _______________________________________________________________________________________

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3. List the activities that helped you reach your goal (s). __________________________________________________

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4. List demonstrations/illustrated talks/speeches given about this project.

Audience to Whom Number of Award or

Date Title Presented People Recognition_______________________________________________________________________________________________________________

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5. I participated in the following leadership/citzenship activities related to this project.

Number of

People

Type of Activity Where Involved Date_______________________________________________________________________________________________________________

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Educational programs of the Kentucky Cooperative Extension Service serve all people regardless of race, color, age, sex, religion, disability, or national origin. Issued in furtherance ofCooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, M. Scott Smith, Director of Cooperative Extension Service,University of Kentucky College of Agriculture, Lexington, and Kentucky State University, Frankfort.Copyright © 2003 for materials developed by the University of Kentucky Cooperative Extension Service. This publication may be reproduced in portions or its entirety for educational ornonprofit purposes only. Permitted users shall give credit to the author(s) and include this copyright notice. Publications are also available on the World Wide Web at www.ca.uky.edu.

Issued 2-88

6. I assisted ________ 4-H’ers with their geology projects. I helped them by:

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7. I collected and identified the following specimens. (Number and list all specimens you have collected this year.Group according to rock, mineral, or fossil. Add more sheets, if necessary.)

Description

Sample Date Name of Type of Where (Color, Mineral/Use

No. Collected Rock Rock Found Texture, etc.) Content

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8. On a separate sheet of paper, in your own words, write a project story telling what you did and learned in thisproject. Include items such as how the project helped you, your family, and others; who assisted you with the project;and how you think this project will be of help to you in the future.

______________________________________________________________________________________________________________________Member’s Signature Date Leader’s Signature Date