Earth Science

1. Earth Science Rocks, dirt and how things work… 

2. Geology Vocab #1 Vocabulary How can you remember it? (draw, paraphrase, etc) • Radioactive Decay • Radiometric Dating • Relative Dating • Law of Superposition • Extrusive • Cross-Cutting • Inclusive • Geologic Time Scale • Faunal Succession • Principle of Uniformitarianism • A process in which radioactive isotopes break down into stable isotopes of other elements. • Determining the absolute age of a sample based on the ratio of parent material to daughter material • Determining whether an object or event is older or younger than other objects or events. • A principle that states that younger rocks lie above older rocks in an undisturbed sequence. • The type of igneous rock that forms when lava or pyroclastic material cools and solidifies on the Earth’s surface. • When an igneous intrusion cuts across existing rock, the intrusion or fault is younger than the existing rock. • The type of igneous rock that forms when lava or pyroclastic material cools and solidifies beneath the Earth’s surface. • A scale that divides the Earth’s 4.6 billion year history into distinctive intervals of time. • Fossil organisms succeed one another in a definite order. • A principle that states that the same geologic processes shaping the earth today have been at work throughout Earth’s history.

3. Geology Vocab #2 Vocabulary How can you remember it? (draw, paraphrase, etc) • Rift • Mid-ocean Ridge • Ocean Trenches • Seafloor Spreading • Magnetic Reversal • *Paleo- • Divergent boundaries • Convergent boundaries • Transform boundaries • Seismic Waves • Asthenosphere • Lithosphere • Old or Ancient • A long mountain chain that forms on the ocean floor where tectonic plates pull apart; usually extends along the center of ocean basins. • Long deep steep troughs in the ocean floor. • The process by which new oceanic lithosphere is created at mid-ocean ridges as older materials are pulled away from the ridge. • The process by which the north and south magnetic poles periodically change places. • Old or Ancient • The boundary between two tectonic plates that are moving away from each other. • The boundary between two colliding tectonic plates. • The boundary between two tectonic plates that are sliding past each other horizontally. • The waves of energy that travel through the Earth. • The soft layer of the mantle on which pieces of the lithosphere move • The outermost, rigid layer of the Earth that consists of the crust and the rigid upper part of the mantle.

4. Flashback Target #3- I can identify the approximate age of the Earth as being 4.6 billion years old. Passing Notes- On the top of your note, write the following questions: How long have humans been on this earth? How old do you think the Earth is and why? Is there an organism that pre-dates (comes before) humans? Pick a question to respond to, respond to it, and then fold your paper up like you would fold a note to a friend.

5. Your Timeline • How old are you? • How can you prove it?? • Trophies with dates and names, scars, major events (birthdays that are documented,

6. The Earth’s Timeline We believe the Earth to be approximately 4.6 billion years old. Why? How do we know? What scars does it have? What major events throughout it’s history can we prove?

7. Timeline Develop your own timeline to show the periods of the geologic time scale. For each period, list 3 facts or pieces of information. It could be organisms that appeared or went extinct, significant events that occurred, etc. You must label each period with the time in Ma. Be accurate with the scale.

8. Key Facts:: 1.Earth is believed to be approximately 4.6 billion years old. 2.The first life, in the form of bacteria, appeared on Earth approximately 3.6 billion years ago. 3.Primitive organisms inhabited Earth long before more advanced ones, such as fish, amphibians, reptiles, and mammals. 4.Human ancestors and modern-day humans are relatively recent arrivals on planet Earth.

9. Relative Dating- What is it?? Dating your relatives???? Nooooooo…silly…. Smh… It’s dating a grouping of rocks or fossils based on their positions RELATIVE to one another. • Ex: “You are older than Jimmy.” Or “You are younger than Casey, but older than Jimmy.” We used your “position” to tell your age, RELATIVE to other people. Just like in rock layers- We use the position of rocks to their approximate age based on comparing them! • The rocks on the bottom layer are older than the rocks on the top layers.

10. 5 Principles of Relative Dating http://prezi.com/5ii3gdmytywf/earth-science-relative-dating/?kw=view-5ii3gdmytywf&rc=ref-2329439 Check out this Prezi to help you study the 5 principles of relative dating!

11. Radiometric Dating- What is it?? • Radiometric dating is a way that we can find out the actual or absolute age of rocks or fossils. • We use the ratio of “parent” isotopes to “daughter” isotopes to measure how old a fossil or rock is. Remember the M&M lab we did? This was to illustrate the term ‘Half-life’. Half-life is the time that it takes for half of the radioactive isotopes to decay. • For example: if we had 100 radioactive isotopes and then 5700 years later we had 50 isotopes, then 5700 would be the half-life (the time it took for half of them to decay).

12. “Clocks in Rocks” • Radiometric dating- Also called Radioactive dating. • Each rock contains certain minerals that have radioactive elements in them. • We use the rate of decay of these elements to decide the “absolute” age of the rocks. • Parent isotope- Daughter Isotope • Began using it in 1905 when Ernest Rutherford discovered the phenomenon

13. 2/11/13 What is an index fossil and what is it used for? Explain your reasoning- Be detailed!! What is the Law of Superposition? Flashback Target #3- I can identify the approximate age of the Earth as being 4.6 billion years old. Target #2- I can use the Principles of Relative Dating to determine relative ages of rocks.

14. Check This Out! • http://geology.com/meteor-impact-craters.shtml

15. Flashback- 2/15/13 Target #1- Define radiometric dating and use it to explain the geological time scale. Target #3- Identify the approximate age of the Earth as being 4.6 billion years old. (You may use notes to answer any flashbacks!) • What is radiometric dating and what is it used for? • How accurate is it? What are some pros and cons of using radiometric dating? If you aren’t sure, make an educated guess! IDK or nothing, doesn’t count!!!

16. Flashback2/18/13 • Write two things that you know about radiometric dating, or something that you read or saw on Friday with Mr. Bland. Turn in to me! 

17. Flashback- 2/19/13 Target #1- Define radiometric dating and use it to explain the geological time scale. Target #3- Identify the approximate age of the Earth as being 4.6 billion years old. Target#2- Use the Principles of Relative Dating to determine relative ages of rocks. (You may use notes and books to answer any flashbacks!) • What’s the difference between relative dating and radiometric dating? • If you were an archaeologist and you were finding ancient human fossils, what kind of dating would you use to find the exact age of the fossil? Why? • If you were an archaeologist and you were looking at the layers of rock on the side of a cliff, which method of dating would you use to find out the approximate ages of the rocks? Why? IDK or nothing, doesn’t count!!!

18. Flashback- 2/21/13 Target #4- Explain how convection currents in the mantle and forces from within the Earth influence and shape the Earth’s surface. (You may use notes and books to answer any flashbacks!) 1. Identify and explain the following: (using either of the red books. LOOK IN THE INDEX! ) • James Hutton Why do we call him the “father of modern geology”? • Alfred Wegener What is his theory? Why did people not believe him? IDK or nothing, doesn’t count!!!

19. Flashback:2/25/13Target # 4:Explain how convection currents in the mantle and forces from within the Earth influence and shape the Earth’s surface. • How do we see the ocean floor? • What do you think is down there (under the ocean)? Why????? • When do you think we discovered what is on the ocean floor?

20. Flashback:2/26/13Target #4 : I can explain how convection currents in the mantle and forces from within the Earth influence and shape the Earth’s surface. • What method of heat transfer causes the plates to move? • How can we tell? • Why does Hawaii have so many islands that make up the state? http://www.iris.edu/hq/programs/education_and_outreach/animations/21

21. Flashback2/28/13Target # 4: Explain how convection currents in the mantle and forces from within the Earth influence and shape the Earth’s surface.Target#5: Explain how some processes can be observed on a human time scale, but other processes take much longer. What tool do seismologists use to measure earthquakes? How does it work? What invention can you come up with that might work better or differently than what they currently use? Day 1

22. Flashback3/1/13Target # 4: Explain how convection currents in the mantle and forces from within the Earth influence and shape the Earth’s surface.Target# 5: Explain how some processes can be observed on a human time scale, but other processes take much longer. • Do earthquakes and volcanoes cause lithospheric plate movement or does lithospheric plate movement cause earthquakes and volcanoes? • How does the Earth’s structure influence the way that seismic waves travel through it? Day 1

23. Name 2 effects of tectonic movement::

24. Flashback • What is the Asthenosphere? Why does it move?

25. Magnetic Reversals • After molten lava emerges from a volcano, it solidifies to a rock. In most cases it is a black rock known as basalt, which is faintly magnetic, like iron emerging from a melt. Its magnetization is in the direction of the local magnetic force at the time when it cools down. • Instruments can measure the magnetization of basalt. Therefore, if a volcano has produced many lava flows over a past period, scientists can analyze the magnetizations of the various flows and from them get an idea on how the direction of the local Earth's field varied in the past. Surprisingly, this procedure suggested that times existed when the magnetization had the opposite direction from today's. All sorts of explanation were proposed, but in the end the only one which passed all tests was that in the distant past, indeed, the magnetic polarity of the Earth was sometimes reversed.

26. Magnetic Reversal • As the "plates" on each side are pulled away, lava emerges from the middle, solidifies and "records" the prevailing magnetic field. The newly formed basalt sticks to the plates and is also pulled away--some of it towards Europe and Africa, some towards America. Every half million years, on the average, the Earth's magnetic polarity reverses, and so does the magnetization of the ocean floor. Each strip therefore represents an epoch of one or the other magnetic polarity, and the symmetry is also explained. It is as if the sea-floor was a giant tape recorder, with twin tapes emerging from the mid-Atlantic ridge, recording the Earth's magnetism at the time they emerge and then traveling in opposite directions. Similar magnetic strips were also observed in all other oceans.

28. Evidence and Methods • Relative dating! 26.2 popcorn reading pg 610

29. Based on your research, do you think that the theory of plate tectonics can help predict where earthquakes are going to occur? What is the value of being able to make such predictions? • 2. According to the theory of continental drift, about 200 million years ago, all the continents used to be part of one supercontinent. Over time, the supercontinent broke up and drifted apart—the separate pieces becoming the continents we know today. According to this theory, what might the Earth look like in about one million years? One hundred million years? • 3. Do you think there is any relationship between where earthquakes occur and where volcanoes erupt? Using your earthquake data, can you predict where volcanoes will occur? • 4. Imagine that you are a geologist called in to work on an international earthquake preparedness plan. What factors would you have to consider? What areas of the world would be targeted? What are the benefits of developing such a plan? • 5. Given the tremendous growth in technology, do you think there is a tool other than a seismograph that could be developed to measure the strength of an earthquake? Try your hand at designing such a device. How would it work? What would it measure? Is it more effective than a seismograph? • 6. Are you surprised at the number of earthquakes that occur on a regular basis? What do you think that the number of earthquakes tells us about the planet Earth?

30. Flashback • What method of heat transfer causes the plates to move? • How can we tell? • Why does Hawaii have so many islands that make up the state?

31. Cool Videos! • http://www.pbs.org/wnet/savageearth/animations/earthquakes/index.html • Earthquake Animation

33. Crust Mantle Outer Core Inner Core Oceanic Crust is more dense- Continental Crust is less dense- If oceanic crust and continental crust were at a convergent boundary, the oceanic crust would sink because it is more dense.

34. Helpful Animations or Short Clips • Plate tectonics http://www.youtube.com/watch?v=nfziy_860GU • Sea floor spreading http://www.youtube.com/watch?v=GyMLlLxbfa4&feature=related • Seismic activity http://www.iris.edu/hq/programs/education_and_outreach/animations/9