relative age and index fossils 1

Do Now: Try to answer these WITHOUT using your notes.

Why won’t you ever find fossils in igneous rocks?

What type of rocks will you find fossils in?

What can scientists determine about an organism from its fossil?

Name one substance in which you could find an entire organism preserved.

Do Now 3.13.171. What land use would be the best choice for watershed drainage?A. mallB. wetlandC. recreational area

2. Where is the majority of Earth’s freshwater located?A. groundwaterB. oceansC. lakesD. Ice

3. What causes upwelling in the oceans?A. coral reef constructionB. photosynthesis reactionsC. winds and ocean currents

Do Now 3.13.171. What land use would be the best choice for watershed drainage?A. mallB. wetlandC. recreational area

2. Where is the majority of Earth’s freshwater located?A. groundwaterB. oceansC. lakesD. Ice

3. What causes upwelling in the oceans?A. coral reef constructionB. photosynthesis reactionsC. winds and ocean currents

Do Now 3.13.171. What land use would be the best choice for watershed drainage?A. mallB. wetlandC. recreational area

2. Where is the majority of Earth’s freshwater located?A. groundwaterB. oceansC. lakesD. Ice

3. What causes upwelling in the oceans?A. coral reef constructionB. photosynthesis reactionsC. winds and ocean currents

Do Now 3.14.171. Which describes the hydrosphere?A. all of Earth’s organisms and the environments in which they liveB. a layer of Earth’s atmosphere made up primarily of concentrated ozoneC. all of the water in Earth’s oceans, lakes, seas, rivers, and glaciers, plus the water in the atmosphere

2. Which provide the best source of information about the quality of water in aquifers?A. wellsB. lakesC. septic tanks

3. Which statement best compares the amount of water present on Earth today with the amount present millions of years ago?A. There is slightly more water on Earth today.B. There is significantly less water on Earth today.C. There is significantly more water on Earth today.D. There is about the same amount of water on Earth today.

Pre & Post Test Google search ncedcloud Log into school net Use your lunch number for username Password: Chargers!15 Post Test code: WY9XE5 Pre Test code: LU8XY4NY8 (write words you

do not know) When you’re done go to study island and READ only Adaptation

Do Now 3.21.161. Most fossils are found in _____ rock.

A. igneous B. metamorphic C. sedimentary D. all of the above

2. What is the approximate age of the oldest ammonite fossil shown in the diagram above?

A. 65 million years B. 248 million years C. 480 million years D. 540 million years

3. Which point shows where a fossil that is 500 million years old would most likely be found?

E F H G

How fossils are the first part of telling a story.

Relative Dating The age of an event or object in relation

to other events or objects

Can you think of any examples?

Remember this is NOT an exact age or date, but an important way to put events or ages of objects in order. It’s the first step to fitting together the puzzle of Earth’s past together.

How old are these bicycles? Can you arrange these bikes in order of their ages without knowing how old each is?

A. B.

C.

Index Fossils are an important tool scientists use to find the relative date of rocks

Index Fossils Fossils found in sedimentary rock can

offer clues about the age of the rock An organism that is fossilized in rock

must have lived during the same time span in which that rock was formed

Index Fossils Therefore, if scientists knew how

long ago a fossilized organism lived, then they could figure out the age of the rock in which the fossil was found.

HOWEVER, not all fossils can be used to date rocks. Why is this?

Index fossils Were common organisms (there were

lots of them around) Lived in many areas (all over the world) Existed only during specific spans of

time

Practice How can you use index fossils to

determine the age of rock layers?

How are index fossils like fashion trends? Index fossils are used to date rocks

Lets look at fashion trends to date when the following pictures were taken…

About when do you think these people are from?

About when do you think these people are from?

About when do you think these people are from?

Exit Ticket 1. Which best describes the relationship between rock layers and index fossils?A. Different rock layers contain only specific species of index fossils.B. Different rock layers can be compared to determine the exact age of index fossils.C. Different rock layers can be determined to be the same exact age if they contain the same index fossils.D. Different rock layers can be determined to be the same relative age if they contain the same index fossils.

2. Which best explains the significance of the trilobite(type of fossil) as an index fossil?A. They were the first fossils to be discovered.B. They are fossils that represent many different life-forms.C. They were the only fossils found outside the United States.D. They are fossils that indicate a certain era in geologic time.