Sea Floor Ages Project:
Part A: Read this Dating article (click here) to learn how scientists determine the age of fossils and rocks then answer the questions below in your performance task.
1. What two techniques do scientists use to date fossils?
2. What is absolute dating?
3. How is absolute dating determined?
4. What is relative dating?
5. How are relative and absolute dating different?
6. How are all carbon atoms similar?
7. what makes carbon isotopes different from one another?
8. Why are some isotopes radioactive?
9. What is the half-life of an isotope?
10. What is the half-life of Carbon-14?
11. What percent of Carbon-14 will be left in a fossil/rock after 11,460 years?
12. What is the law of superposition?
13. What layers of sedimentary rock is older? The bottom layers or the top layers?
14. Fossil A was found in a deeper layer of sedimentary rock than Fossil B. What fossil is older?
15. What can the date of fossils tell you about the layer of rock they are found in?
16. If a scientist performs absolute dating on a fossil and finds that it is 600 Million Years Old, how old is the layer of rock it was found in?
Part B: Using what you learned in Part A, answer the following Radiometric Dating questions in this document (click here) in your performance task.
Part C: Obtain a Seafloor Ages Map template from the teacher or print out your own copy (click here). You will also need colored pencils. The teacher should have some too. Imagine that you are an Ocean Explorer gathering information on the ages of the seafloor in the Pacific and Atlantic Oceans. You and our fellow scientists take the drill ship Resolution to many locations in the oceans and collect rock samples from each sample location on the map lettered 'a-gg'. The ages of each sample are determined in the lab and are listed on the worksheet next to the letter of the rock sample. Now you must color the map based on the ages of the rock samples to see the distribution of seafloor ages. Once finished, take photo of map and upload in performance task. Afterward, answer the questions below.
1. What is the oldest seafloor?
2. Look at the Atlantic Ocean. Where is the youngest seafloor in that ocean?
3. What do you notice about the age pattern on the seafloor in the Atlantic Ocean? (Hint: Look on each side of the middle)?
4. Africa and South America used to be joined together in Pangea, but are now separated by the Atlantic Ocean. Something must be happening between these continents to create new seafloor. Notice how the oldest is on the outside and the newest crust is in the middle of the seafloor. How do you think an age pattern like this forms?
5. Now look at the Pacific Ocean seafloor ages. Where in the Pacific do you notice the same type of pattern as seen in the Atlantic?
6. The central and northern Pacific seafloor ages are more complicated. Where are the youngest ages of the seafloor in this ocean? Are they in the center of the ocean basin?
7. In the Pacific, the seafloor on one side of the youngest crust gets very old, but the seafloor on the other side is much younger. How do you think the location of the youngest aged seafloor in the Pacific Ocean contributes to a more complicated age pattern in that ocean (hint: think about the distance of the youngest seafloor from the nearest continents on both sides of the ocean)?
Part A: Read this Dating article (click here) to learn how scientists determine the age of fossils and rocks then answer the questions below in your performance task.
1. What two techniques do scientists use to date fossils?
2. What is absolute dating?
3. How is absolute dating determined?
4. What is relative dating?
5. How are relative and absolute dating different?
6. How are all carbon atoms similar?
7. what makes carbon isotopes different from one another?
8. Why are some isotopes radioactive?
9. What is the half-life of an isotope?
10. What is the half-life of Carbon-14?
11. What percent of Carbon-14 will be left in a fossil/rock after 11,460 years?
12. What is the law of superposition?
13. What layers of sedimentary rock is older? The bottom layers or the top layers?
14. Fossil A was found in a deeper layer of sedimentary rock than Fossil B. What fossil is older?
15. What can the date of fossils tell you about the layer of rock they are found in?
16. If a scientist performs absolute dating on a fossil and finds that it is 600 Million Years Old, how old is the layer of rock it was found in?
Part B: Using what you learned in Part A, answer the following Radiometric Dating questions in this document (click here) in your performance task.
Part C: Obtain a Seafloor Ages Map template from the teacher or print out your own copy (click here). You will also need colored pencils. The teacher should have some too. Imagine that you are an Ocean Explorer gathering information on the ages of the seafloor in the Pacific and Atlantic Oceans. You and our fellow scientists take the drill ship Resolution to many locations in the oceans and collect rock samples from each sample location on the map lettered 'a-gg'. The ages of each sample are determined in the lab and are listed on the worksheet next to the letter of the rock sample. Now you must color the map based on the ages of the rock samples to see the distribution of seafloor ages. Once finished, take photo of map and upload in performance task. Afterward, answer the questions below.
1. What is the oldest seafloor?
2. Look at the Atlantic Ocean. Where is the youngest seafloor in that ocean?
3. What do you notice about the age pattern on the seafloor in the Atlantic Ocean? (Hint: Look on each side of the middle)?
4. Africa and South America used to be joined together in Pangea, but are now separated by the Atlantic Ocean. Something must be happening between these continents to create new seafloor. Notice how the oldest is on the outside and the newest crust is in the middle of the seafloor. How do you think an age pattern like this forms?
5. Now look at the Pacific Ocean seafloor ages. Where in the Pacific do you notice the same type of pattern as seen in the Atlantic?
6. The central and northern Pacific seafloor ages are more complicated. Where are the youngest ages of the seafloor in this ocean? Are they in the center of the ocean basin?
7. In the Pacific, the seafloor on one side of the youngest crust gets very old, but the seafloor on the other side is much younger. How do you think the location of the youngest aged seafloor in the Pacific Ocean contributes to a more complicated age pattern in that ocean (hint: think about the distance of the youngest seafloor from the nearest continents on both sides of the ocean)?