Downloaded 572 times
Uploaded by21ST CENTURY
GRADE 10 SCI MODULE TEACHER'S GUIDE UNIT 1
This document provides an overview of a 10th grade Science textbook developed by the Department of Education of the Republic of the Philippines. It was collaboratively developed by educators from various educational institutions. The document notes that according to Republic Act 8293, works produced by the Government of the Philippines are not subject to copyright. It also lists the authors and reviewers that contributed to the development of the textbook and provides the table of contents for the first unit which covers Earth and Space topics including Plate Tectonics and the Earth's Interior.
More Related Content
Similar to GRADE 10 SCI MODULE TEACHER'S GUIDE UNIT 1
GRADE 10 SCI MODULE TEACHER'S GUIDE UNIT 1
- 1. 10 Science Department of Education Republicof the Philippines This book was collaboratively developed and reviewed by educators from public and private schools, colleges, and/or universities. We encourage teachers and other education stakeholders to email their feedback, comments, and recommendations to the Department of Education at action@deped.gov.ph. We value your feedback and recommendations. Teacher’s Guide Unit 1
- 2. ii Science – Grade10 Teacher’s Guide First Edition 2015 Republic Act 8293, section 176 states that: No copyright shall subsist in any work of the Government of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for exploitation of such work for profit. Such agency or office may, among other things, impose as a condition the payment of royalties. Borrowed materials (i.e., songs, stories, poems, pictures, photos, brand names, trademarks, etc.) included in this book are owned by their respective copyright holders. DepEd is represented by the Filipinas Copyright Licensing Society (FILCOLS), Inc. in seeking permission to use these materials from their respective copyright owners. All means have been exhausted in seeking permission to use these materials. The publisher and authors do not represent nor claim ownership over them. Only institutions and companies which have entered an agreement with FILCOLS and only within the agreed framework may copy from this Teacher’s Guide. Those who have not entered in an agreement with FILCOLS must, if they wish to copy, contact the publishers and authors directly. Authors and publishers may email or contact FILCOLS at filcols@gmail.com or (02) 439-2204, respectively. Published by the Department of Education Secretary: Br. Armin A. Luistro FSC Undersecretary: Dina S. Ocampo, PhD Printed in the Philippines by: REX Book Store, Inc. Department of Education-Instructional Materials Council Secretariat (DepEd-IMCS) Office Address: 5th Floor Mabini Building, DepEd Complex Meralco Avenue, Pasig City Philippines 1600 Telefax: (02) 634-1054, 634-1072 E-mail Address: imcsetd@yahoo.com Development Team of the Teacher’s Guide Authors: Herma D. Acosta, Liza A. Alvarez, Dave G. Angeles, Ruby D. Arre, Ma. Pilar P. Carmona, Aurelia S. Garcia, Arlen Gatpo, Judith F. Marcaida, Ma. Regaele A. Olarte, Marivic S. Rosales and Nilo G. Salazar. Reviewers: Eligio C. Obille Jr., Marlene Ferido, Ma. Helen DH Catalan, Vic Marie Camacho, Lilia M. Rabago and Cerilina M. Maramag Illustrators: Joseph V. Bales, Ramon C. Gatpo, Regaele A. Olarte, Marivic S. Rosales, Ruel C. Quindoy, Antonio I. Basilla, and Jose Leo Vic O. Albaño DepEd Specialists: Joseph R. Jacob and Maria Amparo R. Ventura Photo Credits: Herma D. Acosta, Dave G. Angeles, Liza A. Alvarez, Ruby D. Arre, Aurelia S. Garcia, Judith F. Marcaida, Regaele A. Olarte, Jane Chavarria and Nilo G. Salazar, Layout Artists: Joselito B. Asi and John Ralph G. Sotto
- 3. TABLE OF CONTENTS Unit1: Earth and Space Introduction .............................................................................................2 Module 1: Plate Tectonics........................................................................3 Overview .......................................................................................... 3 Pre-Assessment ...............................................................................4 What is Plate Tectonics?....................................................................6 Activity 1. Find the Center...........................................................7 Activity 2. Let’s Mark the Boundaries........................................10 Activity 3. Head-On Collision.....................................................12 Part A. Converging Continental Plant and Oceanic Plate...14 Part B. Convergence of Two Oceanic Plates......................14 Part C. Two Continental Plates Converging.....................................15 Activity 4. Going Separate Ways...............................................16 Activity 5. Slide and Shake........................................................18 Activity 6. Drop it Like It’s “Hot Spot”.........................................19 Performance Task............................................................................20 Summary/Synthesis/Feedback.........................................................22 Glossary of Terms.............................................................................24 References and Links.......................................................................26
- 4. Module 2. TheEarth’s Interior...............................................................27 Overview...........................................................................................27 Answers to Pre-assessment............................................................29 Studying the Earth’s Interior.............................................................32 Activity 1. Amazing Waves!........................................................33 The Composition of the Earth’s Interior............................................34 Activity 2. Our Dynamic Earth...................................................36 The Earth’s Mechanism....................................................................37 Activity 3. Let’s Fit it!.................................................................38 Activity 4. Drifted Supercontinent!.............................................38 Activity 5. Split and Separate!....................................................40 Activity 6. How fast does it go?.................................................41 Plate Tectonic Theory Activity 7. Push me up and aside..............................................42 Performance Task............................................................................43 Summary/Synthesis/Feedback........................................................43 Summative Assessment...................................................................46 Glossary of Terms.............................................................................50 References and links........................................................................51
- 5.
- 6.
- 7.
- 8.
- 9.
- 10.
- 11.
- 12.
- 13.
- 14.
- 15.
- 16.
- 17.
- 18.
- 19.
- 20.
- 21.
- 22.
- 23.
- 24.
- 25.
- 26.
- 27. 1 UNIT 1 Earth andSpace
- 28. 2 Unit 1: Earthand Space Introduction In your Grade 9 Science, part of the lessons was about volcanoes. Learners have learned about the position of the Philippines in the Ring of Fire and its relationship to the presence of active and inactive volcanoes in our country. For this quarter, the topics will focus solely on the theory that explains the existence of volcanoes and other geologic features. The learners will work on two modules to understand this theory better. In the first module, learners will use some of the science skills like graphing, measuring, analyzing and interpreting data, and inferring for them to attain the desired outcomes. What are the outcomes that are expected from the learners? First, learners should identify the types of boundaries created because of lithospheric movements. Secondly, they must relate the movement of Earth’s lithosphere to the occurrence of different geologic changes. Finally, the learners will explain the processes that are taking place along the boundaries. In the second module, learners will perform an activity that will allow them to probe the Earth’s interior by analyzing the behavior of seismic waves (Primary and Secondary waves). Learners will also have an opportunity to simulate one of the properties of the materials present in the mantle. Lastly, included in the module, and the most important part is the series of activities that will give learners an idea about the driving mechanism behind the motion of Earth’s lithosphere.
- 29. 3 Content Standard PerformanceStandard The learner demonstrates understanding of the relationship among the locations of volcanoes, earthquake epicenter, and mountain ranges The learners shall be able to demonstrate ways to ensure disaster preparedness during earthquakes, tsunamis, and volcanic eruptions. Overview: In the previous grade level, the students became familiar with the different types of volcanoes. They were also able to determine the factors that give the distinct conical shapes of volcanoes. Lastly, they understood how energy can be harnessed from volcanic activities. In this particular module, the activities included will allow the students to find out what causes volcanism. The learners will also determine the relationship among the locations of volcanoes, earthquake epicenters, and mountain ranges. Furthermore, they will have a chance to figure out what causes the formation of different geologic features such as mountain ranges, volcanic arcs, trenches, mid-ocean ridges, and rift valleys. Learning Competencies/Objectives In this Learner’s Material, the learners should be able to: 1. Describe the distribution of active volcanoes, earthquake epicenters, and major mountain belts. 2. Describe the different types of plate boundaries. 3. Explain the different processes that occur along the plate boundaries. Unit 1 MODULE 1 Suggested time allotment: 12 to 16 hours Plate Tectonics
- 30. 4 Pre-Assessment A. Choose theletter of the best answer. For questions 1 and 2, refer to the figure above: 1. You were provided with data showing the arrival time of the P and S waves recorded from three seismic stations. Which of these can you possibly determine? a. the damage at the focus c. the intensity of the earthquake b. the distance to the earthquake d. the location of the epicenter Answer: d 2. From the seismogram, the distance to the epicenter can be determined by measuring a. the arrival time of surface wave b. the difference in the arrival times of the P and S waves c. the ratio of the amplitude of the largest P and S waves d. the speed of the surface wave Answer: b 3. When two tectonic plates collide, the oceanic crust usually subducts beneath the continental crust because it is a. denser than continental crust c. thicker than continental crust b. less dense than continental crust d. thinner than continental crust Answer: a 4. If you will visit a place in the Pacific known to be along converging plates, which of these should you not expect to see? a. active volcanoes c. rift valleys b. mountain ranges d. volcanic islands Answer: c
- 31. 5 5. You arean oceanographer and want to map the ocean floor on the east coast of the Philippines. As you do your study, you noticed that there is a portion of the ocean floor which is relatively much deeper than the rest. What most likely is that deeper part? a. linear sea c. rift valley b. oceanic ridge d. trench Answer: d 6. What do you expect to find at a mid-ocean ridge? a. relatively young rocks c. thick accumulation of sediments b. reverse fault d. very ancient rocks Answer: a 7. Crustal Plate A is moving away from Crustal Plate B. What is the expected average rate of change in position between A and B? a. a few centimeters per year c. a few millimeters per century b. a few meters per month d. a few millimeters per day Answer: a 8. Which plate boundary is formed between the Philippine Plate and the Eurasian Plate? a. convergent c. reverse fault b. divergent d. transform fault Answer: a 9. Which of these is false true about crustal plates: a. have the same thickness everywhere b. include the crust and upper mantle c. thickest in the mountain region d. vary in thickness Answer: a 10. Which of these is not true about the Philippine Islands? a. Most are part of the Philippine Mobile Belt except for Palawan, Mindoro, and Zamboanga b. formed because of the convergence of the Philippine Plate and the Pacific Plate c. Originated geologically in an oceanic-oceanic convergence d. Some are products of subduction process Answer: b
- 32. 6 What is PlateTectonics? Lithosphere consists of crust and the upper portion of the mantle. Figure 1 in the LM shows two types of crust, the continental crust and the oceanic crust. The continental crust is thicker but less dense than the oceanic crust. Because of the difference in density, continental crust floats higher than the oceanic crust. Figure 1. Kinds of crust The lithosphere is said to be in constant but slow motion. These motions can range widely. The Arctic Ridge has the slowest rate (less than 2.5 cm/yr), and the East Pacific Rise near Easter Island, in the South Pacific about 3,400 km west of Chile, has the fastest rate (more than 15 cm/yr). This movement of the lithosphere is called tectonics. Figure 2 in the LM is a map showing the lithosphere of the Earth divided into segments called plates. But what are the basis of scientists in dividing the lithosphere in such manner? Continental crust Oceanic crust Mantle
- 33. 7 Figure 2. Mapof plate boundaries http://pubs.usgs.gov The next two activities will answer the question posted in previous page. Activity 1 Find the Center Teaching Tips 1. Let the students recall the different types of seismic waves particularly the body waves (Primary and Secondary waves). Students must recall also that Primary waves travel faster than Secondary waves. 2. Explain to them, that because of this difference in velocity between P and S waves, the distance of earthquake epicenter from the recording station can be determined. If they have data from three recording stations, the exact position of an earthquake epicenter can be located using the triangulation method. 3. Introduce Activity 1 “Find the Center,” which will allow the students to use the triangulation method in locating the epicenter of a hypothetical earthquake.
- 34. 8 Answers to questions Usingthe formula d = Where: d=distance (km) Td=time difference of P-wave and S-wave (seconds) Recording station Time difference of P-wave and S-wave (seconds) Distance of epicenter from the station (km) Batangas 44.8 560 Puerto Princesa 32 400 Davao 38.4 480 Since the scale of the Philippine map on page 9 of the LM is 1.5 cm: 200 km, set the drawing compass to the following computed distances on the map. Recording station How to compute the distance on the map Computed distance on the map (cm) Batangas 560 km (1.5 cm/200 km) 4.2 Puerto Princesa 400 km (1.5 cm/200 km) 3 Davao 480 km (1.5 cm/200km) 3.6 Q1. Where is the epicenter of this hypothetical earthquake? Answer: Since the three circles drawn intersect in Cebu City, it is where the epicenter is. Q2. What difficulty will you encounter if you only have data from two recording stations? Answer: Assuming that the two circles will intersect, the circles will intersect at two points. Therefore, there will be two locations that could possibly be the epicenter. The distance-time graph on page 10 of the LM shows that the S-P interval is about 10 minutes. Td ------------ = 100 km 8 seconds
- 35. 9 Q3. What isthe distance of the epicenter from the seismic station? Answer: 9000 km Q4. What do you think is the importance of determining the epicenter of an earthquake? Possible answer: * Locating earthquake epicenters will pinpoint which fault lines are active. Usually, the less active fault line stores great amount of potential energy that could cause major earthquake once released. Therefore, places near fault lines that remain inactive for a long period of time are due to experience a major earthquake. Key concepts: • In order to locate the epicenter of an earthquake, you need to determine the time interval between the arrival of the P and S waves (the S-P interval) on the seismograms from at least three different stations. You have to measure the interval to the closest second and then use a graph (Distance-time graph on page 10 of the LM) to convert the S-P interval to the epicentral distance. • Once you have the epicentral distances, you can draw circles to represent each distance on a map. The radius of each circle corresponds to the epicentral distance for each seismic recording station. Once you have drawn all three circles and located the point where all three intersect, you will have successfully located (triangulated) the epicenter of the earthquake. For instructions on how to perform triangulation method you may visit this website: http://www.youtube.com/watch?v=oBS7BKqHRhs
- 36. 10 Activity 2 Let’s Markthe Boundaries Teaching Tips 1. Let the students look at Figure 2: Map of Plate Boundaries on page 7 and you may ask them the following questions; a. What is the difference between Figure 1 and a regular World map? b. What do you think is the basis of dividing the world in such manner? 2. Introduce to the learners Activity 2 “Let’s Mark the Boundaries” and tell them that the next activity will help them confirm their answers to the last question. Answers to questions: Q5. How are earthquakes distributed on the map? Answer: The world’s earthquakes are not randomly distributed over the Earth’s surface. They tend to be concentrated in narrow zones. Q6. Where are they located? Answer: Some are located near the edges of the continents, some are in mid- continents, while others are in oceans . But not ALL edges of continents,mid-continents,or oceans can be places where earthquake might occur. Q7. Where are places with no earthquakes? Answer: Answers may vary. Some of the possible answers are: large part of the Pacific ocean, northernmost Asia, majority of Europe, eastern portion of North and South America and western Africa. Q8. Why do you think it is important for us to identify areas which are prone to earthquakes? Answer: It is important to identify areas which are prone to earthquakes so that necessary precautions could be done if ever you’re living in one of those places.
- 37. 11 Q9. How arevolcanoes distributed? Answer: Volcanoes are not randomly distributed. Majority of them are found along the edges of some continents. Q10. Where are they located? Answer: Majority are found along the edges of some continents, particularly in the western coast of North and South America, East and South East Asia. Q11. Based on the map, state a country that is unlikely to experience a volcanic eruption? Answer: Answers may vary Q12. Compare the location of majority of earthquake epicenters with the location of volcanoes around the world. Answer: Earthquake epicenters and volcanoes are both situated at the same locations. Q13. How will you relate the distribution of mountain ranges with the distribution of earthquake epicenters and volcanoes? Answer: Mountain ranges are found in places where volcanoes and/or earthquake epicenters are also located. Q14. What do you think is the basis of scientists in dividing Earth’s lithosphere into several plates? Answer: Geologic activities such as seismicity (occurrence of earthquake), volcanism and mountain formation are the basis of scientists in dividing Earth’s lithosphere. Key concepts: • Plates are large pieces of the upper few hundred kilometers of Earth that move as a single unit as it floats above the mantle. • The plates are in constant motion. As they interact along their margins, important geological processes take place, such as the formation of mountain belts, earthquakes, and volcanoes.
- 38. 12 To view aninteractive map that will show the relationship between plate boundaries and different geologic processes, you may visit; http://ees.as.uky. edu/sites/default/files/elearning/module04swf.swf Activity 3 Head-On Collision Teaching tips: 1. Let the students recall that there are two types of crust, continental and oceanic. Between the two, the oceanic crust is denser. 2. Introduce to the students that plates could either be a continental crust-leading plate or an oceanic crust-leading plate. 3. Introduce the next activity, Part A “Converging Continental plate and Oceanic plate.” This activity will allow the students to determine the effects of colliding oceanic and continental plates. Answers to Questions: Part A: Converging Continental Plate and Oceanic Plate Q15. What type of plate is Plate A? What about Plate B? Why did you say so? Answer: Plate A is an oceanic plate because it is relatively thinner compared to plate B. While Plate B is a continental plate because it is thicker and floats higher than the other plate. Q16. Describe what happens to Plate A as it collides with Plate B? Why? Answer: Plate A bends downward because Plate A is denser than Plate B. Tell the students that this sinking of plate beneath the other plate is called subduction. Point out also to the students that, because of the subduction process, a depression on the ocean floor called trench is also formed. Q17. What do you think will happen to the leading edge of PlateAas it continues to move downward? Why? Answer: The leading edge of Plate A will start to melt because the temperature beneath the crust (mantle) is higher.
- 39. 13 You may addthe fact that as the plate moves deeper into the mantle, it carries with it water which also causes the melting of rocks. Q18. What do you call this molten material? Answer: This molten material is called magma. Q19. What is formed on top of Plate B? Answer: Volcanoes are formed on top of Plate B. Tell the students that volcanoes are mountains that are built by the accumulation of their own eruptive products such as lava. Parallel to the trench, point out in the diagram that volcanoes are formed. Q20. As the plates continue to grind against each other, what other geologic event could take place? Answer: Earthquake could take place as the plates continue to grind against each other. Key concepts: 1. During the convergence of an oceanic plate and a continental plate, the denser oceanic plate slides under the continental plate. This process is called subduction. 2. Geologic events such as formation of volcanoes and trenches as well as occurrence of earthquake will take place because of this process. You can end the lesson at this point. An animated diagram of subduction process can be seen on this website; http://earthguide.ucsd.edu/eoc/teachers/t_tectonics/p_subduction.html
- 40. 14 Part B: Convergenceof Two Oceanic Plates Teaching tips: 1. Recall the subduction process and the geologic events that will take place because of the process. 2. Tell the students that two oceanic plates could also collide because of plate tectonics. 3. Introduce the next activity. This time the students will use the knowledge they acquired from the previous activity in predicting what events could take place due to this type of collision. 4. You may ask the students to draw a diagram showing what they think would be the outcome of this event. Q21. What are the geologic processes/events that will occur out of this plate movement? Answer: Possible answers are: • Plate B undergoes subduction process or the sinking of plate towards the mantle. • Earthquakes can happen since the two plates are grinding against each other. • Trench/es will form. • Volcanoes will form at the surface of Plate A. Q22. What geologic features might form at the surface of Plate A? Answer: Volcanoes might form at the surface of Plate A. The volcanic deposits pile up until they break through the surface of the ocean and form an island arc. Examples of island arcs created in this way are the Aleutians, the Kuriles, Japan, and the Philippines. Q23. If the edge of Plate A suddenly flicks upward, a large amount of water may be displaced. What could be formed at the surface of the sea? Answer: Tsunami is formed at the surface of the sea.
- 41. 15 Key concepts: 1. Whentwo oceanic plates converge they also undergo subduction process. This gives rise to the formation volcanic island arcs, trenches and generates shallow, intermediate, or deep earthquakes. 2. Strong earthquakes generated at the ocean floor may cause displacement of large volume of water and launch big waves called tsunami. Part C: Two Continental Plates Converging Teaching tips: 1. You may start the lesson by asking questions such as; a. What is the highest peak in the Philippines? Mt. Apo about 3144 meters b. How about the highest mountain in the world? Mt. Everest c. Do you have any idea how tall Mount Everest is? 8848 meters d. How do you think most of the tall mountains of the world are formed? 2. Just gather all the ideas the students will mention regarding the last question. After all the ideas had been presented, tell them that they will check their answers after they perform the next activity. Q24. What happened to the strips of clay as they were pushed from opposite ends? Answer: The strips of clay buckled upward. Q25. If the strips of clay represent the Earth’s lithosphere, what do you think is formed in the lithosphere? Answer: Mountains are formed in the lithosphere. Q26. What other geologic event could take place with this type of plate movement aside from your answer in Q25? Answer: Earthquakes will occur due to the collision of the two plates. (Since there is no subduction, only shallow earthquakes will happen) Q27. In terms of the consequences on the Earth’s lithosphere, how will you differentiate this type of convergent plate boundary with the other two? Answer: Since the two plates involved are both continental plates there is no subduction process (because both plates are low in density). As a result, mountains are formed instead of volcanoes.
- 42. 16 Key concept: 1. Whentwo continental plates meet head-on, neither is subducted. Instead, the crust tends to buckle and be pushed upward causing formation of mountain ranges and other highlands. Activity 4 Going Separate Ways Teaching tips: 1. You may start the lesson by saying this: “In a convergent plate boundary, the leading plates undergo destruction process as the crust is consumed in the mantle. But what do you think is happening on the other end of each plates?” (creation of new crust) (We cannot expect that the students will be able to answer this question correctly. This will just serve as the springboard for the next lesson.) 2. To find out the answer to this question, students will study the next type of plate boundary-the Divergent plate boundary. 3. The next activity “Going Separate Ways,” will require students to analyze four pictures. The two topmost pictures are rift valleys while the bottom two are oceanic ridges. Answers to Questions: Q28 What are common in the four pictures? Answers: All four pictures show a fissure or a crack between two land masses. Q29. What do you think is happening to the Earth’s crust in those pictures? Answer: The land masses are moving away from each other. Q30. If this event continues for millions of years, what do you think will be the effect on the crust? Answer: The distance between the land masses will be far greater than what is shown in the picture. Q31. Complete the drawing below to illustrate your answer in question number 3.
- 43. 17 Answer: The illustrationof the students should show a wider crack or fissure between the two land masses. Key concepts: 1. Divergent boundaries occur along spreading centers where plates are moving apart and new crust is created by magma pushing up from the mantle. 2. Effects that are found at a divergent boundary between oceanic plates include: a submarine mountain range such as the Mid-Atlantic Ridge; volcanic activity in the form of fissure eruptions; shallow earthquake activity; creation of new seafloor; and a widening ocean basin. 3. If a divergent boundary is between continental plates, the effects are: rift valley formation which will soon develop into linear sea; shallow earthquake activities, and numerous normal faults. After millions of years
- 44. 18 Activity 5 Slide andShake Teaching tips: 1. The next activity will be a simulation-type activity where students will simulate how transform-fault boundary is formed. 2. After the activity has been performed, you may ask the following questions: a. If the blocks of wood were plates, what kind of plate boundary is formed between Blocks 1 and 2? between 3 and 4? (divergent) b. Describe the relative motion of Blocks 2 and 3; Blocks 1 and 3; Blocks 2 and 4. (Same answer with guide questions 3 and 4) 3. Inform the students that this is another type of plate boundary called transform-fault boundary. 4. Tell students that most transform-fault boundaries are found in the ocean basins. Only few of which are found in the continents. The best example of transform-fault boundary in a continent is the San Andreas Fault. 5. Ask the students what they think would the consequence be if plates move horizontally past each other, (Shallow earthquakes). Answers to Questions: Q32. Were you able to pull the blocks of wood easily? Why or why not? Answer: No, because of the friction between the edges of the block of wood. Q33. What can you say about the relative motion of Blocks 1 and 2? How about Blocks 3 and 4? Answer: Block 2 is moving away from Block 1, while Block 3 is moving away from Block 4. Q34. How will you describe the interaction between Blocks 2 and 3 as you pull each block? Answer: Blocks 2 and 3 are sliding past each other.
- 45. 19 Q35. What isthe interaction between Blocks 1 and 3? How about between Blocks 2 and 4? Answer: Block 3 is sliding past block 1 while Block 2 is sliding past Block 4. Key concepts: 1. Transform-fault boundaries are where two plates are sliding horizontally past one another. 2. Most transform faults are found on the ocean floor. They commonly offset active spreading ridges, producing zig-zag plate margins, and are generally defined by shallow earthquakes. Activity 6 Drop It Like It’s “Hot Spot” Teaching tips: 1. Show the students an aerial picture of the Hawaiian islands.http:// www.aimforawesome.com/media-photos-ebooks-audio-videos/ photos/hawaiian-islands-aerial-satellite-photograph/ 2. Tell them that the Hawaiian islands are volcanic islands. 3. Let them realize that Hawaii is situated in the middle of Pacific plate and not along the plate boundaries. Ask them what gives rise to Hawaiian islands. 4. Introduce to them the next activity which is about intraplate activities. 5. The activity will simulate how hot spots give rise to volcanic islands. 6. You can also watch a video clip on this website:http://www.youtube. com/watch?v=AhSaE0omw9o Answers to questions Q36. What can you see on the surface of the paper? Answer: The surface of the paper which is directly in contact with the test tube became wet. Q37. Let’s say that the paper represents the Earth’s crust; what do you think is represented by the water in the test tube? Answer: Magma from the mantle is represented by the water in the test tube.
- 46. 20 Q38. What geologicfeature do you think will be formed at the surface of the crust? Answer: Volcanoes will be formed. Q39. Which of the features at the surface of the crust will be the oldest? the youngest? Label these on your paper. Answer: The oldest volcano will be the first one that developed while the youngest volcano is the last one that was formed. Q40. Which of the features will be the most active? The least active? Label these on your paper. Answer: The most active volcano is the youngest one (the one that is currently on top of the magma source). While the least active volcano, is the oldest (because it is already cut-off from the source of magma). Key concepts: 1. A “hot spot” is an area in the mantle from which hot materials rise as a thermal plume. 2. High heat and lower pressure at the base of the lithosphere (tectonic plate) facilitates melting of the rock. This melt, called magma, rises through cracks and erupts to form volcanoes. 3. As the tectonic plate moves over the stationary hot spot, the volcanoes are rafted away and new ones form in their place. This results in chains of volcanoes, such as the Hawaiian Islands. Performance Task Teaching tips: 1. The students will be asked to prepare an emergency kit for the whole family that they can use during or after a disaster. 2. This activity will require weeks of preparation on the part of the students. Assign this activity weeks before the actual lesson. 3. Some items needed in the kit may be costly, but as much as possible let us encourage the students to do their best to complete their kits.
- 47. 21 4. Let studentspresent their emergency kits in the class and explain why they think those items must be included in the kit. 5. Encourage debate and discussion. 6. Emphasize that an emergency kit must be prepared ahead of time, not right before or during an emergency 7. The scoring rubric below can be use in evaluating the emergency kit of the students. 1 pt. 2 pts. 3 pts. 4 pts. Survival Kit Items None of the items are necessary for survival during or after a disaster. . A few of the items are clearly necessary for survival during or after a disaster. At least 8 items are clearly necessary for survival during or after a disaster. At least 10 items are clearly necessary for survival during or after a disaster. Labels and Uses None of the items are labeled properly and there is no reason for including it in the survival kit. A few of the items are labeled properly and a reason for each item is included on a separate sheet of paper. At least 8 of the items are labeled properly and a reason for each item is included on a separate sheet of paper. At least 10 items are labeled properly and a reason for each item is stated on a separate sheet of paper. Neatness and Effort exerted The kit is not organized. It looks like the student threw it together at the last minute without much care. The kit is somewhat organized and it looks like the student ran out of time or didn’t take care of the project The kit is done well with some organization and labeling. It appears the student worked hard on it. The kit is neatly organized and labeled as necessary. Much time and effort were put into creating this project
- 48. 22 Emergency kit checklist source: http://www.redcross.org/ • Water—one gallon per person, per day (3-day supply for evacuation, 2-week supply for home) • Food—non-perishable, easy-to-prepare items (3-day supply for evacuation, 2-week supply for home) • Flashlight • Battery-powered radio • Extra batteries • First aid kit • Medications (7-day supply) and medical items • Multi-purpose tool • Sanitation and personal hygiene items • Copies of personal documents (medication list and pertinent medical information, proof of address, deed/lease to home, passports, birth certificates, insurance policies) • Cell phone with chargers • Family and emergency contact information • Extra cash • Emergency blanket • Map(s) of the area Summary/Synthesis/Feedback • According to the plate tectonics model, the entire lithosphere of the Earth is broken into numerous segments called plates. • Each plate is slowly but continuously moving. • As a result of the motion of the plates, three types of plate boundaries were formed: Divergent, Convergent, and Transform fault boundaries • Divergent boundary is formed when plates move apart, creating a zone of tension. • Convergent boundary is present when two plates collide. • Transform fault is characterized by plates that are sliding past each other. • Plate tectonics give rise to several geologic features and events.
- 49. 23 Answers to thesummative assessment: 1. Any of these three are the possible answers: mountains, volcanoes or trenches. 2. d 3. b 4. Transform-fault boundary 5. a 6. b 7. d 8. a and f 9. b and e 10. c and d
- 50. 24 Glossary of Terms Continentalvolcanic arc. Mountains formed in part by igneous activity associated with subduction of oceanic lithosphere beneath a continent. Convergent boundary. A boundary in which two plates move toward each other, causing one of the slabs of the lithosphere to subduct beneath an overriding plate. Crust. The outer portion of the earth. Continental Crust. The thick part of the Earth’s crust, not located under the ocean. Oceanic Crust. The thin part of the Earth’s crust located under the oceans. Divergent boundary. A region where the crustal plates are moving apart. Earthquake. Vibration of Earth due to the rapid release of energy. Fault. A break in a rock along which movement has occurred. Fracture. Any break in a rock in which no significant movement has taken place. Geology. The science that studies Earth. Hot spot. A concentration of heat in the mantle capable of creating magma. Magma. A mass of molten rock form from a depth, including dissolved gases and crystals. Mid-ocean ridge. A continuous mass of land with long width and height on the ocean floor. Plate. Rigid sections of the lithosphere that moves as a unit. Plate tectonics. A theory which suggests that Earth’s crust is made up of plates that interact in various ways, thus producing earthquakes, mountains, volcanoes and other geologic features. Primary (P) wave. The first type of seismic wave to be recorded in a seismic station.
- 51. 25 Rocks. Consolidated mixtureof minerals. Secondary (S) wave. Second type of earthquake wave to be recorded in a seismic station. Seismogram. A record made by a seismograph. Seismograph. A device used to record earthquake waves. Subduction. An event in which a slab of rock thrusts into the mantle. Transform fault boundary. A boundary produced when two plates slide past each other. Trench. A depression in the seafloor produced by subduction process. Volcanic Island arc. A chain of volcanoes that develop parallel to a trench.
- 52. 26 References and Links Departmentof Education, Bureau of Secondary Education. Project EASE Integrated Science 1, Module 12: Inside the Earth. Department of Education, Bureau of Secondary Education (2013). Science Grade 8 Learner’s Module. Vibal Publishing House, Inc. Tarbuck, E.J. et al. (2009). Earth Science 12th ed. Pearson Education South Asia Pte Ltd. http://www.skoool.ie/ accessed March 3, 2014 http://earthds.info/ accessed March 3, 2014 http://eqseis.geosc.psu.edu/ accessed March 4, 2014 http://thehistoryofthephilippines.blogspot.com/ accessed March 4, 2014 http://www.platetectonics.com/ accessed March 5, 2014 http://geology.com/ accessed March 5, 2014 http://www.nws.noaa.gov/ accessed March 6, 2014 http://csep10.phys.utk.edu/ accessed March 6, 2014 http://pubs.usgs.gov/ accessed March 6, 2014 http://www.moorlandschool.co.uk/earth/tectonic.htm accessed March 7, 2014 http://stream2.cma.gov.cn/pub/comet/Environment/TsunamiWarningSystems accessed March 3 2014 http://marc.fournier.free.free.fr accessed July 1, 2014 https://www.bucknell.edu/majors-and-minors/geology/location/geologic- history-of-central-pennsylvania/plate-tectonics.html accessed July 1, 2014 http://www.adelaidenow.com.au/ accessed July 2, 2014 http://www.wildjunket.com/ accessed July 2, 2014 http://www.jnb-birds.com/ accessed July 2, 2014 http://www.geo.hunter.cuny.edu/ accessed July 2, 2014 http://wowlegazpi.com/mayon-volcano-interesting-facts/#sthash.Q3mSKqYG. dpbs accessed July 2, 2014
- 53. 27 Content Standard: The learnersshall demonstrate an understanding of: The relationship among the locations of volcanoes, earthquake epicenters, and mountain ranges Performance Standard: The learners shall be able to: 1. demonstrate ways to ensure disaster preparedness during earthquakes, tsunamis, and volcanic eruptions; and 2. suggest ways by which he/she can contribute to government efforts in reducing damage due to earthquakes, tsunamis, and volcanic eruptions. Overview The topic on Plate Tectonics and the processes within the Earth’s interior conclude the spiralling concepts in Geology. In fact, Geology is the only strand discussed in Grade 10 Science because of the topic’s broadness. In this module, we focus on the Earth’s interior structure and processes. It is also discussed how these processes could possibly have affected the Earth’s surface and caused its physical appearance. There are seven activities in this module which slowly develop the concept of relating the Earth’s interior processes with the physical structure of the Earth’s surface. Unit 1 MODULE 2 Suggested time allotment: 15 to 18 hours The Earth’s Interior
- 54. 28 After allthese activities, a performance task is provided to connect and conclude the two modules for Earth and Space in this grade. The task is very important for the learners to understand the nature of our home planet and to instil in them how they could be part of reducing the risks brought by geologic phenomena. In the discussion, it would be best if the teacher focuses and directs the students towards the development of concepts by answering the following key questions: Learning Competencies In this module, you should be able to: 1. Describe the internal structure of the Earth. 2. Discuss the possible causes of plate movement. 3. Enumerate the lines of evidence that support plate movement.
- 55. 29 Answers to Pre-Assessment Directions: A.Choose the letter of the correct answer. For questions 1 and 2, refer to the figure below that shows the cross section of the Earth as seismic waves travel through it. Seismic waves as they travel through the Earth 1. An S-wave shadow zone is formed as seismic waves travel through the Earth’s body. Which of the following statements does this S-wave shadow zone indicate? a. The inner core is liquid. b. The inner core is solid. c. The mantle is solid. d. The outer core is liquid. Answer: D
- 56. 30 2. Why arethere no P-waves or S-waves received in the P-wave shadow zone? a. P-waves are aboserbed and S-waves are refracted by Earth’s outer core. b. P-waves are refracted and S-waves are absorbed by Earth’s outer core. c. Both the P-waves and S-waves are refracted by Earth’s outer core. d. Both the P-waves and S-waves are absorbed by Earths outer core. Answer: B 3. What makes up the lithosphere? a. Continental crust b. Crust and the upper mantle c. Oceanic crust and continental crust d. Upper mantle Answer: B 4. Miners dig into the Earth in search for precious rocks and minerals. In which layer is the deepest explorations made by miners? a. Crust c. Mantle b. Inner core d. Outer core Answer: A 5. How do you compare the densities of the Earth’s crust, mantle and core? a. The mantle is less dense than the core but denser than the crust. b. The mantle is less dense than both the core and the crust. c. The mantle is denser than the core but less dense than the crust. d. The mantle is denser than both the core and the crust. Answer: A 6. The movement of the lithospheric plates is facilitated by a soft, weak and plastic-like layer. Which of the following layers is described in the statement? a. Asthenosphere c. Lithosphere b. Atmosphere d. Mantle Answer: A 7. Alfred Wegener is a German scientist who hypothesized that the Earth was once made up of a single large landmass called Pangaea. Which of the following theories did Wegener propose? a. Continental Drift Theory c. Plate Tectonics b. Continental Shift Theory d. Seafloor Spreading Theory Answer: A
- 57. 31 8. If youare a cartographer, what will give you an idea that the continents were once joined? a. Ocean depth b. Position of the south pole c. Shape of the continents d. Size of the Atlantic Ocean Answer: C 9. Which observation was NOT instrumental in formulating the hypothesis of seafloor spreading? a. Depth of the ocean b. Identifying the location of glacial deposits c. Magnetization of the oceanic crust d. Thickness of seafloor sediments Answer: B 10. As a new seafloor is formed at the mid-ocean ridge, the old seafloor farthest from the ridge is destroyed. Which of the stated processes describes how the oceanic crust plunges into the Earth and destroyed at the mantle? a. Convection b. Construction c. Diversion d. Subduction Answer: D
- 58. 32 B. Answer brieflythe following questions. 1. What are the different layers of the Earth? Answer: The different layers of the Earth are the crust, the mantle, and the core. The core is made up of a solid inner core and liquid outer core. 2. Why is there a need to study the Earth’s layers? Answer: We need to study the Earth’s layers because the mechanisms in the inner layers facilitate the slow changes that occur on the Earth’s surface. Although these changes takes millions of years to shape the Earth, the tectonic activities that go along with these changes affect us very much. 3. What proves the existence of the boundary between the crust and the mantle? Answer: As seismic waves pass from the crust to the mantle, the velocity increases. If the velocity of waves changes, it means that the density of the media where they travel through are different, and thus proves a boundary. 4. What are the characteristics of the asthenosphere? Answer: The asthenosphere is the soft weak layer below the lithosphere. It has a temperature that facilitates a small amount of melting that gives it the capability to flow. 5. What do the shapes of the continents now tell us about their past? Answer: The shape of the continents seems like a jigsaw puzzle when put together. A picture will be formed and indicate that the continents were once together in the past. Studying the Earth’s Interior The knowledge about seismic waves is very important in understanding the discovery of the different layers of the Earth as well as in determining the properties of these layers. If the students are able to understand the characteristics of seismic waves, they will be able to relate how each layer of the Earth was discovered. The following activity will make the learners differentiate the types and understand the characteristics of seismic waves. It will prepare them in learning the properties and composition of the different layers of the Earth. The teacher can make it as an individual activity for fast-paced learners or as a group activity for those who are more inclined to group discussion.
- 59. 33 Activity 1 Amazing Waves! Ingiving points to students’ responses, you may refer to the following: 5 points – a graphic organizer that is complete and comprehensive 4 points – one part of the organizer is not filled but the given ideas are correct 3 points – two parts of the organizer is not filled but the given ideas are correct 2 points – two parts of the organizer is not filled and some of the given ideas are not correct 1 point – three parts of the organizer is not filled and some of the given ideas are not correct 0 point – no effort exerted
- 60. 34 Answers to questions: Q1.Differentiate surface waves from body waves. Surface waves travel only on the Earth’s surface like ripples of water while body waves travel through the Earth’s body (interior). In addition, surface waves arrive last at seismic recording stations compared to the body waves. Q2. Which type of wave do you think were useful to seismologists in their study of the Earth’s interior? Explain your answer. The body waves were used by seismologists because they can pass through the Earth’s interior. Allow to perform this activity in a way that the students will realize that it takes different properties (like reflection and refraction properties of waves) and characteristics to analyze and differentiate the media where they travel through. Discuss the characteristics of the seismic waves and how these characteristics led to the discovery of each layer of the Earth. The Composition of the Earth’s Interior As the teacher continues to discuss with the layers of the Earth, the teacher may opt to use a boiled egg that is cut across to represent the Earth and to demonstrate each layer. The teacher may ask the students to tell the limitations of the model to determine their understanding. In describing the lithosphere and asthenosphere, the teacher may use the cracked shell to represent the lithosphere and soft butter to represent the asthenosphere. Have the students slide the shell cracks over the soft butter. This will give them the idea how the lithosphere ride over the asthenosphere. The ability of the asthenosphere to flow slowly is termed as plasticity. To further demonstrate the characteristic of the asthenosphere, the teacher may do Predict-Observe-Explain for the following activity, before the readings and discussion of the mantle. This is to affirm the correctness of ideas cited and rectify misconceptions that may arise upon doing the activity. Post the questions on the board: “How will the mixture of cornstarch and water react? Will it act as liquid, solid or gas? The teacher writes the answers of the learners on the board but should not expect that they will give correct answers. Let the learners observe as the teacher performs the activity. After the activity is done, the teacher should correct the misconceptions of the students during the discussion.
- 61. 35 Demonstration: Simulating Plasticity (Adapted) Materials • 15 g cornstarch • 2 small cups • 20 ml tap water • medicine dropper • stirring rod or spoon Procedure: 1. Put 15 g cornstarch into one of the beakers. Put 10 ml water into the other beaker. 2. Add one drop full of water to the cornstarch. Stir the mixture. Ask the students the question: How does the mixture react like; solid, liquid or gas? 3. Continue to add water to the mixture, one drop full at a time. Stir the mixture after each addition. 4. Stop adding water when the mixture becomes difficult to stir. 5. Pour the mixture into your hand. 6. Roll the mixture into a ball and press it. Let the students explain what they have observed. Facilitate the students’ reactions with the following questions: Q1. How does the mixture behave like? A1: It behaves like solid. Q2. How is the mixture of cornstarch and water similar to the Earth’s mantle? A2: The mixture of cornstarch and water behaves like the mantle. It has the ability to flow slowly.. Q3. How is it different from the Earth’s mantle? A3: The cornstarch gained mobility due to addition of water while the mantle’s plasticity is due to partial melting aided by the heat of the inner layers of the earth. Q4. How does the plasticity of the Earth’s mantle influence the movement of the lithospheric plates?
- 62. 36 A4: Since themantle is capable of flowing slowly, it carries and facilitates the movement of lithospheric plates above it as it moves. Activity 2 Our Dynamic Earth Activity 2 will test the learners’ understanding on the different characteristics, properties and composition of the Earth’s layers. If possible, make it as an individual activity. Expected Output: Answers to questions: Q3. What element is the most abundant in the Earth’s crust? Oxygen is the most abundant element in the Earth’s crust. Q4. What elements make up most of the mantle? The elements silicon, oxygen, iron and magnesium make up the mantle.
- 63. 37 Q5. What isthe special feature of the upper mantle? The upper mantle has with it a soft weak layer called the asthenosphere, which is capable of flowing. This property facilitates the movement of the lithospheric plates. Q6. How did scientists discover that the outer core is liquid? The scientists were able to show that the outer core is liquid due to the fact that S- waves cannot travel through this Earth’s layer as proven by the S-wave shadow zone. Q7. What materials make up the inner core? The inner core is mostly made up of iron and nickel. Q8. Is the inner core solid, liquid or gas? What keeps it in this phase? The inner core is solid. This is due to the very high pressure that keeps it compacted together even if the temperature is really very high. Q9. Compare the inner core and the outer core. The outer and the inner core are made mostly of iron and nickel. The outer core reaches a temperature of 2000o C. With this temperature, the iron and nickel melt thus, this layer is liquid. The inner core has a temperature as high as 5000o C. It is compact despite of the very hot temperature because of the very great pressure that keeps this layer in the solid phase. The Earth’s Mechanism The teacher may introduce the lesson by linking the concept of the Earth’s interior structure with its interior processes, and then the effects of these processes. The teacher may ask this question: “Is the Earth’s interior processes related with the structure of the Earth’s surface?” Encourage responses from the students.
- 64. 38 Activity 3 Let’s Fitit! Divide the class into groups of 3 to 4 students and perform the activity as a group. This will serve as the teacher’s springboard to the next activity. The students’ reasoning ability will be enhanced. Conduct this activity as quickly as possible. Answers to questions: Q10. What features of the newspaper helped you to connect the pieces perfectly? Pictures and words in the newspaper helped us to connect the pieces perfectly. Q11. How do the lines of prints or texts in the newspaper help you to confirm that you have reassembled the newspaper/magazine page? The lines of prints make sure that the newspaper is fitted well. The words written serve as clues in connecting the pieces of newspaper together. The completed/connected words confirm that the newspaper has been reassembled. Q12. Show proofs that the newspaper is perfectly reassembled. The answers may vary. - The picture in the newspaper if completed. - The broken words were completed/connected. Activity 4 Drifted Supercontinent! Answers to questions: Q13. What does the Glossopteris fossils tell us about the early positions of the continents? Since it is impossible for Glossopteris fossils found in different regions or continents to be blown by the wind or carried by ocean waves, the only possibility is that these regions were once connected.
- 65. 39 Q14. If Glossopterisfossils were found in Antarctica, what does this indicate about the climate of this continent before? It proves that Antarctica had a tropical climate before. Q15. If the climate and the position of a place are relative to each other, where then was the initial location of Antarctica 250 million years ago? It tells us that Antarctica was nearer to the equator before as compared to where it is today. Q16. What does the presence of Mesosaurus fossils tell about the initial location and position of South America, Africa, and Antarctica? It tells us that these continents were connected before, since this kind of animal cannot swim across the vast ocean. Q17. What clues are useful in reconstructing Pangaea? The edges of the continents are useful in reconstructing Pangaea. Aside from the fitting of edges of the continents, the presence of evidences found in the same continents made the reconstruction easier. Q18. Which continents do you think were neighbors before? Possible answers: Europe and Asia were neighbors in the north. North America, South America and Africa in the middle. Australia and Antarctica, together with India in the South. Q19. Will there be a possibility that the current location of a continent would be different 100 years from now? Yes, if the continents continue to move. But it will not be very noticeable because it took 200 million years before the continents came to where they are now, based on the Continental Drift Theory. Q20. Where do you think was the Philippines located during the time that the Pangaea existed? Research on how the Philippine islands emerged. Knowing that the Philippines has or is near trenches, it could have not existed during the time of Pangaea but borne out of volcanic eruptions and other tectonic activities.
- 66. 40 Q21. If thecontinents will continue to move, try to predict the Philippines’ location 100 million years from now. Answers may vary. For the purpose of facilitating learning and in preparation for the class discussion, the teacher must perform the activity first before letting the students do it in the class. Activity 5 Split and Separate! (Adapted) Answers to questions Q22. What do the stripes in the paper represent? The stripes represent the rocks with normal and reverse polarities. Q23. What does the middle slit represent? What occurs in this region? The middle slit represents the mid-ocean ridge where the actual seafloor - spreading occurs. Q24. What is the role of the mid–ocean ridge in the movement of lithospheric plates? The mid-ocean ridge serves as the origin of lithospheric movement. It is the place where the force that pushes the lithosphere originates. Q25. How does the new seafloor form at the mid-ocean ridge? Hot, less dense material below the Earth’s crust rises towards the mid-ocean ridge. As this material flows sideways, it creates a crack in the crust where magma will flow out. This magma cools down and becomes the new seafloor. Q26. What process/es happen at the side slits? The side slits serve as subduction zone where the old seafloor plunges beneath another tectonic plate.
- 67. 41 Q27. Is theearth getting larger and wider when plates drift away from each other? Explain briefly. The Earth is not getting larger or smaller. If there is the production of a new seafloor in the mid-ocean ridge, there is a destruction of an old seafloor at subduction zones. Activity 6 Adapted (Glencoe Earth Science student edition copyright 2002) In this activity, students will compute for the rate of seafloor spreading. After the activity, they will be able to determine the distance a continent moves for every year. Reiterate to the students that NOT ALL plates move at the same rate. How fast does it go? Magnetic Polarity Map Answers to questions Q28. How far do the plates move away from each other every year? Answer: 2.5 cm per year Q29. If Africa is approximately 2,400 km away from the Mid-Atlantic Ridge, how long ago was it when Africa was directly at or near the Mid-Atlantic Ridge? Answer: 96000000 years or 96 million years After the activity, the teacher must relate the creation of a new seafloor with the one that causes it. This will pave the way to the concept of convection current.
- 68. 42 Recall the mechanismsof the Earth’s interior structure and properties. The teacher must make a strong idea about the properties of the mantle and the process it undergoes. This will lead the learners to connect the Seafloor Spreading Theory with the convection current that happens in the mantle. For Activity 7, the teacher must perform the activity first before letting the students perform so he could facilitate the class. The teacher must constantly remind the students to be extra careful in handling heating materials. Activity 7 (Adapted) Push me up and aside! Answers to questions Q30. How does the food coloring react? The food color rises and moves to the sides of the beaker then sinks. It demonstrates a cyclic motion. Q31. What do you call this behavior? This is called convection current. Q32. Enumerate the factors that cause the formation of a current. The difference in density in the molecules is caused by the difference in temperature. The rate of heating at the bottom and the rate of cooling at the top. Amount of heat supplied to the substance. Q33. What happens to the blocks? What does this resemble? The blocks are pushed up to the middle of the boiling water and then swayed towards the sides of the beaker. The small, light wood blocks resemble the lithospheric/tectonic plates that moved about slowly along the tectonic boundaries, pushing, sliding past and drifting away from each other because of convection current.
- 69. 43 The teacher shouldexplain that these are the possible causes of tectonic activities. Again, reiterate that the processes/activities in the Earth’s interior play a role in the processes along Earth’s surface. The teacher may opt to end the lesson with a video presentation on the evolution of the Earth or a video on how magnificent the Earth is if there are available videos that can be downloaded from the internet. The teacher should also emphasize that it is impossible to stop these tectonic activities from happening, but we can do something to mitigate their effects. Performance Task This is the performance task for the students. This activity shows the effects of geologic activities like volcanic eruptions and earthquake. This could be an individual or a group activity which aims to motivate students to be part in mitigating the effects of tectonic activities. 1. The teacher gives a situation where the students acts as a project engineer who wants to develop a subdivision, a realtor who sells a house & lot, a geologist visiting his/her hometown or simply a student seeking to help the government. However, the students are given an option to choose other characters in the society. 2. The performance task must be given at the start of the first grading period. 3. This should be presented at the end of the grading period. 4. The teacher must set a date for the learners’ to present their outputs in class.
- 70. 44 5. The teachermay consider the following rubric in rating the students. Criteria 4 3 2 1 Score Details and information Has included 5 things or more to remember before, during and after any tectonic activity. Has included 4 things to remember before, during and after any tectonic activity. Has included 3 things to remember before, during and after any tectonic activity. Has included 2 things to remember before, during and after any tectonic activity. Method of Presentation The method of presentation is easy to understand, unique and outstanding. The method of presentation is unique and organized. The method of presentation is organized but not unique. The method of presentation is not organized and not unique. Technique/ Creativity The presentation/ medium includes unusual and interesting features and components that excite the audience about the topic and add to the meaning. The presentation / medium includes some unusual and interesting features that interest the audience and relate to the meaning. The presentation / medium include unusual and interesting features, but they do not add to its meaning. The presentation / medium does not include unusual or interesting features. Accuracy Information contains no error. Information contains minimal error, none of which interferes with the clarity of communication Information contains minimal errors, of which interferes with the clarity of communication Information contains many errors. Feedback The clientele understood well the purpose and objective was attained. The clientele understood a little the purpose and objective was somewhat attained. The clientele understood the purpose. The clientele ignored the purpose.
- 71. 45 Summary/Synthesis/Feedback • The Earthis composed of three main layers: the crust, mantle, and core which is subdivided into outer core and inner core. • The crust is the outermost and thinnest layer of the Earth. • The mantle is the middle layer of the Earth. It makes most of the Earth’s volume and mass. • The crust and a part of the upper mantle make up the lithosphere. The lithosphere is subdivided into portions called lithospheric plates. • The asthenosphere is the weak layer of the mantle on which the lithosphere floats. • The outer core is made up of molten material. The outer core accounts for the Earth’s magnetic field. • The inner core is the deepest layer of the Earth. It is made up of solid nickel and iron. The temperature in the inner core reaches as high as 5000oC. • The speed, reflection and refraction properties of seismic waves are used by scientists to study the structure and composition of the Earth’s interior. • The Continental Drift Theory of Alfred Wegener states that the continents were once a part of a large landmass called Pangaea which splits apart and the continents moved away from each other towards their current positions. • Alfred Wegener based his theory on evidences from fossils embedded in rocks and rock formations. • Seafloor spreading is believed to occur as hot magma rises at the rift in the mid-ocean ridge. This magma cools down and becomes the new seafloor as it pushes the former. • The old seafloor is destroyed at the subduction zone and melts inside the mantle. • The age of rocks and the magnetic stripes in the ocean floor support the seafloor spreading theory. • The theory of plate tectonics helps explain the formation and destruction of the Earth’s crust and its movement over time. • Scientists believe that the plates’ movement is due to convection currents in the mantle.
- 72. 46 Summative Assessment A. Choosethe letter of the correct answer. 1. In 1912, Alfred Wegener proposed a theory that the Earth is once a single landmass. What is the name of the Mesozoic Supercontinent that consisted of all of the present continents? a. Eurasia b. Laurasia c. Pangaea d. Gondwanaland Answer: C 2. Who were the two scientists who proposed the theory of seafloor spreading in the early 1960s? a. Charles Darwin and James Hutton b. Harry Hess and Robert Dietz c. John Butler and Arthur Smite d. F. Vine and D. Mathews Answer: B 3. Which of the following diagrams best illustrates the convection occurring in the mantle? A. C. B. D. Answer: A
- 73. 47 4. During the1960s, scientists were already equipped with gadgets needed to explore the deep ocean. What discovery about the ocean floor is associated with the seafloor spreading? a. Mountains are denser than the mantle. b. The rotational poles of the Earth have migrated. c. The crust of the continents is denser than the crust of the ocean. d. The crust of the ocean is very young relative to the age of the crust of the continents. Answer: B 5. If the Atlantic Ocean is widening at a rate of 3 cm per year, how far (in kilometers) will it spread in a million years? a. 3 kilometers b. 30 kilometers c. 300 kilometers d. 3000 kilometers Answer: B 6. Which of the following increases with distance from a mid-ocean ridge? a. the age of oceanic lithosphere b. the thickness of the lithosphere c. the depth to the sea floor d. all of the above Answer: D 7. Which of the following can you infer from the continuous movement of the lithospheric plates over the asthenosphere? a. All the continents will cease to exist. b. All the volcanoes in the Philippines will become inactive. c. The continents will not be located in the same place as they are now. d. The islands of the Philippines will become scattered all over the world. Answer: C
- 74. 48 8. If allthe inner layers of the Earth are firm solid, what could have happened to Pangaea? a. It remained as a supercontinent. b. It would have become as it is today. c. It would have slowly disappeared in the ocean. d. It would have stretched and covered the whole world. Answer: A 9. Why does the oceanic crust sink beneath the continental crust at the subduction zone? a. The oceanic crust has a greater density. b. The oceanic crust is pulled downward by Earth’s magnetic field. c. The oceanic crust is pushed from the ridge. d. The continental crust has a denser composition. Answer: C 10. The lithospheric plates are believed to be moving slowly. What is the driving force that facilitates this movement? a. gravitational force of the moon b. magnetic force at the poles c. convection current in the mantle d. the force of the atmosphere Answer: C
- 75. 49 B. Complete theconcept map below on continental drift, seafloor spreading, and plate tectonics. Plate Tectonic Theory
- 76. 50 Glossary of Terms Asthenosphere.Soft, weak upper portion of the mantle where the lithospheric plates float and move around. Continental Drift Theory. States that all the continents were once one large landmass that broke apart and where the pieces moved slowly to their current locations. Convection current. Current in the mantle due to the heat from the inner layers of the Earth and is the force that drives the plates to move around. Lithosphere. The topmost, solid part of the Earth that is composed of several plates. Lithospheric Plates. The moving, irregularly shaped slabs that fit together to form the surface of the Earth. Mid-ocean ridge. Area in the middle of the ocean where new ocean floor is formed when lava erupts through the cracks in the Earth’s crust. Mohorovicic Discontinuity (Moho). The boundary that separates the crust and the mantle. Plasticity. The ability of solid to flow. Seafloor spreading. A process by which new ocean floor is formed near the mid-ocean ridge and moves outward. Subduction. The process in which the crust plunges back into the Earth. Tectonics. Branch of Geology that deals with the movements that shape the Earth’s crust.
- 77. 51 References and links Borrero,Francisco et al. (2008). Earth Science: Geology, the Environment, and the Universe. The McGraw-Hill Companies, Inc. Department of Education, Bureau of Secondary Education. Project EASE Integrated Science 1, Module 12: Inside the Solid Earth Department of Education, Bureau of Secondary Education (2013). Science – Grade 8 Learner’s Module. Vibal Publishing House, Inc. Feather Jr.,Ralph et al. (2002). Glencoe Earth Science. The McGraw-Hill Companies, Inc.. Maton, Anthea et al. (1999). Exploring Earth Science. Prentice Hall. Tarbuck, E.J. et al. (2009). Earth Science 12th ed. Pearson Education South Asia Pte Ltd.
- 78. 52 Internet http://www.geomag.bgs.ac.uk/education/reversals.html accessed March1, 2014 https://www.princeton.edu/~achaney/tmve/wiki100k/docs/Asthenosphere.html accessed March 1, 2014 http://www.learner.org/courses/essential/earthspace/session3/closer2.htm accessed March 3, 2014 http://loki.stockton.edu/~hozikm/geol/Courses/The%20Earth/Content%20Web %20Pages/Bugielski/webpage.htm accessed February 28, 2014 http://www.cyberphysics.co.uk/topics/earth/geophysics/Seismic%20Waves% 20Reading.htm accessed March 1, 2014 http://rieson.blogspot.com/2013/02/birth-of-earth.html accessed March 1, 2014 http://www.yourdictionary.com/magnetic-reversal accessed March 31, 2014 http://www.learner.org/courses/essential/earthspace/session3/closer2.htm accessed March 3, 2014 http://www.enchantedlearning.com/subjects/dinosaurs/glossary/Contdrift.html accessed March 7, 2014