Stories from the Fossil Record Link

PART 1, Relative Age:

Please complete the sequence of activities so that you can be well prepared for the mastery check.

1. Define the following terms related to relative age. Once you have a definition that fits the context of our science class, draw an image that fits with the definition. You may choose to create the image as you work through the content of the next few activities. Use your own notebook paper to complete this task. Refer to this Quizlet for definitions.
- cross-cuting relationship
- extrusion
- horizontality
- index fossil
- intrusion
- lateral continuity
- relative age
- superposition
- trilobite (this definition is not in quizlet, but you will get it when you move on through the learning…)
- unconformity
- uniformitarianism

2. Whodunit? Check out this link and try to decipher what happened! Record your thoughts on your notebook paper, then check your work against the key (posted in the classroom). After doing so, identify how this activity is a good analogy for relative age. Hint: look at your definition of relative age to make sure you've got the right idea.

CHECK IN! Please turn in your answer to the analogy question to your teacher!

3. Watch this video clip on the Law of Superposition - if this doesn't work, try this linked version. As you watch, please answer the following questions. You do not need to write the question, just write your answer. Record this on you notebook paper.
a. How do you know that the fault came after the initial rock layers formed?
b. What evidence exists that the erosion happened before the lava flow?
c. How do you know the intrusion happened most recently (after all of the horizontal layers)?
Check your work against the key that is posted.

4. Wondering what some of these key vocabulary terms are? Thinking you could make an analogy to sandwiches (or think I'm crazy?)? Check out this image for some clues as to what superposition, horizontality and lateral continuity mean.

5. Try it!
a. Try this animation. You will need to click on the large image in order to begin.
b. Look at this image and try to determine in what order the events occurred. Write the letter (A, B, C, D, E) that represents each outcrop of rock in order from oldest (happened a long time ago) to youngest (happened most recently). Jot these five letters into your notes. Check your work before moving on.
c. Here's another image. Learn from your experience in the previous activity. Write the letters that correspond to the layers of rock in order from oldest to youngest on your notebook paper. Check your work with your teacher when you think you've got it.
d. Now for the challenging one - click on this image for a real doosey! This time, you will use letters A-I. Record your answer, from oldest to youngest, on your notebook paper, then check your work.

6. Online reading… Click on this link to take you to an article, "Earth's History and Clues from Fossils." As you read, please address each of the following questions. Record your answers on your notebook paper.
a. How does a single fossil or set of fossils help geologists to decipher the geological history of an area?
b. How is an index fossil used to identify a time period?
c. Why are the fossils of marine organisms sometimes found in rock units at the tops of high mountains? What evidence would you look for to determine if this reason is plausible?

7. Watch this video clip on index fossils. As you watch, please record your answers to the following (feel free to push pause and play as needed to get the information).
a. Name the four characteristics that all index fossils have in common.
b. Draw a picture of some of the more common index fossils mentioned in the video:
- ammonite
- trilobite (note: this also needs to be a part of you definitions/images from part 1)
c. Explain how index fossils help to date (estimate when it formed) layers of rock and/or other fossils.

8. Watch this simple animation to see how fossils can help to place rock layers in relative order. You will need to click on the "forward" or "backwards" bottoms below the image to move forward or backwards in time.

9. Practice! See your teacher for a set of "layers" to try to place in relative age order. You will "fossils" found in each layer to help place the layers in order.
a. The first set has letters that are used to represent fossils found in different layers. In order to be successful, you will have to make sure that there is one letter in the layer above and below that is the same. When you think you've got it, check in with your teacher to ensure you are accurate.
b. With the second set, you will be placing rock layers in relative order in the same way, only this time you will use the actual fossils instead of letters. One fossil must be present in the previous (bottom) and the above (more recent) layers; it does not have to be the same fossil each time. When you are finished, check your work with your teacher.

CHECK IN! See how well you are understanding this so far by taking this brief self-assessment. Check your answers before moving on. If you missed any, make sure you understand WHY before you go to the next step.

10. Go back to your initial definitions and diagrams/images. Make sure you have all the definitions and images complete. Review these before taking the mastery check. You may even want to quiz each other!

CHECK IN! When you are confident with your understanding of the content to this point, you can take the mastery check. You only have one retake opportunity over this content, so be sure you are ready before you attempt it for the first time. Here is a list of what the mastery check will cover:
• Terms to Know = uniformitarianism, relative age, superposition, intrusion, index fossil
• Understand how to interpret rock layers and the fossils found within them in order to determine relative age (similar to the activities in #5, 8, 9, & 10).

PART 2, Absolute Age:

Please complete the following activities to become familiar with the concept of absolute age, which is a different way to determining how old rock is on Earth.

1. Understand some key vocabulary terms. Use the quizlet for this section for help. Get the definitions for each term and then as you progress, come up with a diagram/illustration that shows the meaning of the term. Do this on a sheet of notebook paper (you can continue from the previous section if you have space).
- absolute age
- atom
- carbon-14
- electron
- element
- half life
- isotope
- neutron
- proton
- radioactive dating
- radiometric dating
- stable element

2. Watch the introduction video. As you watch, pay attention to what kind of rock CAN be dated using this process and which kind of rock CANNOT. Record this on your notebook paper.

3. Here is another video clip that will get more involved with how absolute age can be calculated. If the first link doesn't work, try this one.
a. As you watch, please try to draw and label what he draws as he shares the information. Record these answers on your notebook paper. This will include:
- a volcano
- a close up of material that comes out of the volcano (atoms within the lava/magma)
- a graph of "half-life"
b. In math class, this kind of graph is referred to as ---. (Fill in the blank.)

4. In preparation for a lab you will be doing, please watch this example of how radioactive decay works.

5. Now it's your turn! Get the materials for the lab from your teacher. This will include a lab handout.

6. Try the electronic version of this process. You will need to download the electronic simulation in order to use it. You will also need a copy of the handout to complete as you work. You can get that from your teacher.

7. Read an article called, "World's Oldest Rock" and answer the questions on your notebook paper.
a. How old is the rock in the article? How does that compare to the age of Earth?
b. Where was the rock found?
c. Explain how scientists would go about finding the age of the rock described in the article.

8. Go back to your definitions and ensure you have a drawing or diagram of some kind for each term.


Part 3, Compare relative and absolute age

The next task will be for a mastery check grade. You will have to compare

1. Read this article prior to doing the Venn Diagram. As you read, please answer the question, How are both types of dating used together to help us understand Earth's past? You can do this on a sheet of notebook paper. This needs to be done so you are ready to take the mastery check (Venn Diagram comparing relative and absolute age) by the beginning of class on Monday, March 9.

2. Make sure you are ready by reviewing the following concepts:
Relative Age:
- uniformitarianism
- relative age
- superposition
- intrusion
- index fossil

Absolute Age
- radioactive decay
- half-life
- absolute age
- stable element
- read a graph of exponential decay (like what you created with the Skittles lab)