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Week 4/5: Limestone & Rock ages
Week 4/5: Limestone & Rock ages
MondayWarm Up: Write two things you still need to finish in order to be prepared for your presentation tomorrow.
LT: I can make a presentation about my solution to a science or engineering problem to the class with my group.
Glacier Project
1. Pick a group of 3-4 people. Choose wisely!!2. Pick a scientific question or engineering problem about glaciers (look at our
class list for ideas) that you want to investigate.3. Get your topic approved by Ms. P4. Use the engineering design process or scientific method to answer your
question or solve your problem! Work as a group and fill in scientific/engineering report!
5. Make poster explaining your project6. Present project to the class! (Tuesday)
Presentation Guidelines
- 5-8 minutes long- Presentation needs to include:
- Explanation of the problem/research question- The steps you took to solve your problem/answer your question- Your solution- Limitations/challenges you might face when building your design or running your experiment
- Every group member must speak during presentation- Must have a poster that explains the problem and your solution (with
drawings!)- You must ask one question about a different groups project after their
presentation
TuesdayWarm Up: List at least three impacts melting glaciers could have on the environment or on society.
LT: I make a presentation about my solution to a science or engineering problem to the class with my group.
Presentation Guidelines
- 5-8 minutes long- Presentation needs to include:
- Explanation of the problem/research question- The steps you took to solve your problem/answer your question- Your solution- Limitations/challenges you might face when building your design or running your experiment
- Every group member must speak during presentation- Must have a poster that explains the problem and your solution (with
drawings!)- You must ask one question about a different groups project after their
presentation
WednesdayWarm Up: Write down two new things you learned during yesterday’s presentations.
LT: I can define Calcium Carbonate and identify at least 5 different forms of limestone.
Focus: Limestone
- Review: Sedimentary rock, contains calcite, very hard- Formed in marine areas- Marine animals with shells and skeletons die and
accumulate on the bottom of the ocean- Skeletons and shells are broken down into sediments
which settle down in the bottom of the ocean and eventually turn into limestone
Can learn a lot of important information from studying the layers of limestone worldwide and in the grand canyon.
Your Task: - Read p. 68-71 in book- Answer “Think
questions” on p. 71 with a partner. Discuss first, then write down answers on blank piece of paper. Turn in ONE sheet for you and your partner
Calcium Carbonate
- Major component of limestone- Calcium Carbonate = chemical name for CALCITE- Contains CARBONATE which breaks down in
presence of acid (fizzes)- 15% of earth’s sediments/sedimentary rock, 2%
earth’s crust- Also main ingredient in chalk, travertine, cave
deposits, marble, and invertebrate shells- Seawater contains ingredients that react with
each other to form calcium carbonate: calcium and bicarbonate
Forms of Limestone: Reef Limestone
- Mainly composed of skeletons of marine animals, such as corals
- Form in warm, tropical areas - Sections of Redwall Limestone in
the GC include fossil corals...there must have been a warm, tropical sea present at one time
Forms of Limestone: Chalk
- Composed of almost pure calcite- Powdery, fine-grained rock- Ex: White Cliffs in Dover, England
Forms of Limestone: Coquina
- Made up of sorted and cemented fossil debris, mostly small shells and shell fragments
- A soft limestone
Forms of Limestone: Freshwater Limestone
- Can be identified by the types of fossils it contains
- Less common than limestone from marine origin
- Often contains snail shells
Forms of Limestone: Ooliths
- Small grains of sand, silt, or shells around which layers of calcium carbonate have been deposited
- Forms in warm, shallow conditions in mud- Particles move back and forth and calcite
coats them, then they are cemented together
- Forming on the Bahama bank off the coast of Florida
Forms of Limestone: Tufa
- Forms in cool freshwater that is rich in calcium carbonate
- Helps build stalactites and stalagmites in caves and can build precipitate “towers”
- Ex: Mono Lake, CA
Forms of Limestone: Travertine- Calcium Carbonate rock that is harder and denser than tufa- Deposited around hot springs- Ex: Yellowstone National Park
ThursdayWarm Up: What is Calcium Carbonate? List at least three different forms of limestone.
LT: I can explain how sediment layers form and how sediment layers are studied.
Discussion Questions:
- How does sedimentation occur?- Where do sediments go when they are
added to water?- How do they form layers?
Basin Demo...
- Creating a model of sedimentation- Why is there water in the basin?- Add sediment each class period…- Predict: what will the basin look like after several days?- Predict: what would happen if we tilted the basin?
Layers stay HORIZONTAL!
Key Term: Principle of Original Horizontality
Sediment layers are generally deposited in a horizontal or nearly horizontal position
https://www.youtube.com/watch?v=mbQ8AIUJ7rg
Key Term: Superposition
Sediment layers are deposited in a time sequence, with the oldest on the bottom and the youngest on the top
Key Term: Uniformitarianism
The theory that states that changes in the earth’s crust during geological history have resulted from the action of continuous and uniform processes.
EXAMPLES:
- Gravity- Animals hunting- Babies growing - Erosion occurring
UNIFORMITARIANISM:
- The idea that the way things happen today is the same way things have always happened
- Scientists use observations about processes happening today to infer what happened in the past
Discussion Question:
How can we tell how old rock layers are? What are clues in the rocks? What tests should be run?
- Brainstorm with your table group and make a list!
Stratigraphy
Study of the distribution and sequence of sedimentary rock layers
- William “strata” smith- Realized that if two rock layers or strata contain the same
group of fossils they must be the same age
Discussion Question
What are some clues we can look for in a rock layer that can give us insight into the environment in which it formed?
Fossils, types of particles, crossbedding
Fossil
Definition: Any evidence of past life preserved in the earth’s crust
“The present is the key to the past”
Video
Fossilization: https://www.youtube.com/watch?v=4-dTz416rYg
Your Task: - Read p. 73-75 “popcorn style” as a class- Work with a partner to answer questions
on p. 75...write in complete sentences!
Friday 11/18 - periods 1,3,5
Monday 11/21 - periods 2,4,6Reading GC Rocks
Warm Up: What is stratigraphy?
LT: I can use rock and fossil evidence to make inferences about different grand canyon rock layers.
Recap- Law of Original Horizontality - Superposition- Uniformitarianism- Stratigraphy
Studying GC: https://www.youtube.com/watch?v=XxF4okURxek
Fossil
Definition: Any evidence of past life preserved in the earth’s crust
“The present is the key to the past”
Your Task:
- Complete the column “Environmental Interpretation WS” in pairs
- You may use:- Notes from journal- Science text books - p. 38-41
Part 1 together...
Kaibab Formation
Appears that it is composed of limestone. How and where does limestone form?
Forms when calcium carbonate precipitates from water and or shells. It is deposited under water, usually an ocean
What kinds of fossils are found in the Kiabab Formation?
Sponges, corals, brachiopods, clams, snails
Where do these types of animals live today?
In the ocean, some in freshwater
What does the evidence tell you about the environment where Kaibab formed?
Probably under water, maybe an ocean
Your Task:
- Complete the column “Environmental Interpretation WS” in pairs
- You may use:- Notes from journal- Science text books - p. 38-41
Part 1 together...
