Lesson 1_ Volcanoes, Earthquake and Mountain Ranges.pptx

Lesson 1_ Volcanoes, Earthquake and Mountain Ranges

1. Earth and Space: Volcanoes, Earthquakes, Mountain Ranges and Earthquake Epicenter

2. WORD SEARCH PUZZLE:

3. What is Plate Tectonics? Lithosphere consists of crust and the upper portion of the mantle. 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. Continental crust Oceanic crust Mantle Figure 1

4. Map of plate Boundaries According to the plate tectonics model, the entire lithosphere of the Earth is broken into numerous segments called plates (see Figure 2). Figure 2

5. Map of plate Boundaries 7 relatively large plates And a number of smaller ones, including the Philippine plate

6. Map of plate Boundaries The plates move very slowly but constantly, and this movement is called tectonics thus, the theory of moving lithospheric plates is called plate tectonics.

7. Activity 1: Find the Center What is the difference between P waves and S waves?

8. Primary (P-waves), Secondary (S-waves), and Long surface waves (L-waves). The first two travel into the Earth’s interior while the last one on the surface. These waves travel at different velocities; thus, do not arrive at a seismic recording station at the same time. The farther the recording instrument is from the focus, the greater the difference in arrival times of the first P-wave compared to the first S-wave. The difference in the arrival time will tell us the distance of the earthquake’s focus from the seismic recording station However, it does not tell in which direction it came from.

9. the epicenter can be determined using the triangulation method. It uses distance information from three seismic stations to locate the earthquake epicenter. On a map, circles are drawn around each seismic station. The radii of the circles are scaled to the estimated distance from the station to the earthquake. The three circles will intersect at one point that locates the earthquake.

10. DISTANCE-TIME GRAPH But, if the earthquake took place at a far greater distance, seismologists use the distance-time graph similar to the figure 2 in determining the location of the epicenter.

11. The distance-time graph above shows that the S-P interval is about 10 minutes. Q3. What is the distance of the epicenter from the seismic station? Q4. What do you think is the importance of determining the epicenter of an earthquake?

12. Map of earthquake distribution (Red, green, and blue dots represent earthquake epicenters)

13. Q5. How are earthquakes distributed The world’s earthquake are not randomly distributed over the Earth’s surface. They tend to be concentrated in Narrow Zones.

14. Q6. Where are the located? Some are located near the edge of the continents, some are in mid-continents, while others are in the oceans.

15. Q7. What are places with no earthquake? Large part of Pacific Oceans Northernmost Asia Majority of Europe Eastern portion of North and South America Western Africa

16. Q8. Why do you think it is important for us to identify areas which are prone to earth quake? It is important to Identify areas which are prone to earthquake so that necessary precautions could be done if ever you’re living in one of those place.

17. How are volcanoes distributed? Volcanoes are not randomly distributed. Majority of the are found along the edge of some continents,

18. Where are they locate? Majority are found along the edges of some continents, particularly in the western coast of North and South America, East and South East Asia.

19. Based on the Map, state a country that is unlikely to experience a volcanic Eruption

20. Q12: Compare the location of majority of earthquake epicenters with the location volcano around the world? Earthquake epicenters and volcanoes are bith situated the same locations.

21. Q13: How will you relate the distributions of mountain Mountain ranges are found in places where volcanoes and/ or earthquake epicenters are also located.

22. What do you think is the basis of scientist in dividing the Earth's lithosphere? Answer: Geologic activities such as seismicity (occurrence of earthquake), volcanism and mountain formation are the basis of scientists in dividing Earth’s lithosphere.