Plate Tectonics GIS Activities

Transcription

1 Plate Tectonics GIS Activities Introduction A Geographic Information System (GIS) is a system designed to capture, store, manipulate, analyse, manage, and present all types of geographical data. In the simplest terms, GIS is the combination of map making (cartography) and data analysis all undertaken by a computer program. What is GIS? (2.5 mins) The Geographic Information Systems (GIS) viewer that we will use for these activities is made up of a database. It is the information in the database, that creates the maps and the overlay layers that you will be using. Lesson summary The Orientation shows you how to access the GIS viewer and introduces you to the tools. Part A introduces how the layers work in the GIS viewer and also provides further practice with the tools. Part B explores the relationships between the tectonic plates, earthquakes, volcanoes, plate boundaries and resulting landforms. Part C develops and tests two hypotheses (or theories) to understand the relationship between earthquake magnitude and date of event and their impact on people. Remember: Computer steps are shown by a symbol Questions to be answered are numbered. Orientation How to access the GIS viewer and an introduction to the tools Open your browser and go to the following website The page may take a minute or two to load be patient! The base map will load first then the other data layers. If it stops at any point, just click the refresh button on your browser.. You will see a map of the world that looks like this.

2 On the left side of the map is a list of the data Layers, which are linked to this GIS viewer. The boxes, which have a tick in them, are the ones, which are turned on and are currently open so the information from these layers is visible to you you can see it! In the upper right corner are the Tools for this GIS viewer. If your map is especially small on your screen complete the following steps: Select the Zoom In tool. Move the mouse over to the left-hand side of the map, just north of North America. Left click the mouse then drag the mouse to the bottom right corner of the map. A red border should appear and the area you have selected will be highlighted. When you release the mouse, the map will enlarge automatically. If you make a mistake, don t worry! Select the Zoom to Full Extent tool and the map will return to its original size. Spend a few minutes exploring the tools. Zoom In: draw a box around the area you want to examine more closely. Fixed Zoom In: zooms into the map by a fixed amount with each click i.e. you see a smaller area. Pan: push the map view around the screen. Zoom to Previous Extent: takes you back to the view you last had. Identify Feature: provides information about the item, which has been clicked on. Measure Distance: identify the two points you wish to measure the distance between. Click on the first location and then drag the mouse to the second location and then release. A line is drawn between the two points. Ensure you record the distance in kilometres. Click on the line to delete it. Zoom Out: draw a box around the area you want to back out to a larger area. Fixed Zoom Out: zooms out of the map by a fixed amount with each click i.e. you see a larger area. Zoom to Full Extent: this will take you to the full extent of the map. For this map the full extent is the world. Zoom to Next Extent: takes you back to the view you last had. Draw on Map: this tool allows you to draw or annotate on the map. Clear Drawing: clear your drawings/annotations using this tool. 2

3 Help! Where am I? If you get totally zoomed in or out or are not sure where you are, don t panic! You can get back to the original view. Select the Zoom to Full Extent tool and the map will return to its original size. Part A How layers work and further practice with tools Turn off (untick) all the layers in the Layers menu on the left-hand side of the map. 1. Describe what you see now. This is known as the base map and all the other layers are linked to this base map. Turn on (tick) the Ocean and Country 2010 layers. 2. What do you see now? Using either the Zoom In tool or the Fixed Zoom In tool, change the view of the map so that Australia is much bigger. Use the Measure Distance tool to find the distance from the west coast of Australia to the east. 3. The distance from the west coast of Australia to the east is km Tick on the pink line to delete it. Select the Identify Feature tool and then click on Australia. A table should appear with lots of different information in about Australia. Use the scroll bar at the bottom of the table to access all the columns. 4. a. What country name is in the Name_1 column? b. What was the population in 2005? (POP2005_1) c. What was the population in 2010? (POP2010_1) d. Did life expectancy increase or decrease between 2005 and 2010? Provide data in your answer to prove your decision. (LEXP2005 and LEXP2010) 3

4 Close this table. Select the Pan tool and move around the Asia Pacific Region. Using the Identify Feature tool, select a different country and then answer the following questions. 5. a. What is the name of your chosen country? (Name_1) b. What was the population in 2005? (POP2005_1) c. What was the population in 2010? (POP2010_1) d. Did life expectancy increase or decrease between 2005 and 2010? Provide data in your answer to prove your decision. (LEXP2005 and LEXP2010) Close this table. Using the Pan and Zoom In tools, select any region of the world and make it fit the screen. Using the Draw On Map tool, draw a picture on your map. If you would like to save your picture, select File, Save As in the top left hand corner. To clear the map, select the Clear Drawing tool. Select the Zoom to Full Extent tool to return to the original map (if the map if too small then enlarge it). Investigate what happens to the map when some layers are ticked and others are not. 6. What layers did you find most useful to have on together? Explain your answer. Part B Exploring the relationships between tectonic plates, earthquakes, volcanoes, plate boundaries and landforms. Ensure that only the following layers are turned on (ticked): Volcanoes, Country 2010 and Ocean. What is spatial distribution? Spatial distribution is the arrangement of objects or features on the Earth s surface. As Geographers we look at features and see if they form any kind of pattern. For example, are the features dispersed i.e. are they spread out evenly? Are the features clustered i.e. are they grouped together? Are the features linear i.e. are they in a line? Are the features in a radial pattern i.e. are they arranged like the spokes on a bicycle wheel? Or are the features random i.e. there is no identifiable pattern? 4

5 1. Using the world map on the GIS viewer and the PQE approach below, complete the description of the spatial distribution of volcanoes in North and South America, by filling in the gaps. P - describe the general Pattern shown on the map Q - use appropriate examples and statistics to Quantify the pattern E - identifying any Exception to the general pattern The general pattern of volcanoes in North and South America shows that they are located on the coast of the continents creating a pattern. Of all the volcanoes located in North and South America approximately per cent can be found along the coast. Some exceptions to this pattern can be found in the United States of America where some volcanoes can be found up to km inland from the coast. (Hint: you could use the Measure Distance tool to help with this last answer). The next question will form part of your assessment for this task. When you have completed your answer, copy and paste it into a different document and save it as GIS Map Assessment in your Geography folder. Turn on (tick) the Plates layer. 2. Using the world map showing volcanoes and the PQE approach shown above, describe the spatial distribution of volcanoes in relation to the plate boundaries. (3 marks) In GIS, spatial data is classified as point, line or polygon (area). Features are almost always shown in one of these forms. Point A point feature has a specific location on a map. It is shown usually by a symbol to show where it is located e.g. a building, traffic lights or toilets. Line Line features will have a beginning and an end (but these will not always be on the map). Line features are either real e.g. roads or creeks or artificial e.g. state boundaries. Polygon A polygon is an enclosed area. It will have at least three sides and will have an area and a perimeter e.g. a park, paddocks or a council district. 3. Are the volcanoes you are looking at point, line or polygon data? Right click on the Volcanoes in the data layer table and open the Attribute Table. 5

6 Drag down the right hand corner of the table to make it bigger. This is the data which is used to create the map showing the volcanoes of the world. Each red triangle on the map will be in this table and will have its own row of attribute data i.e. data that is attributed or linked to it. 4. Complete the table below to explain what each of the attributes mean. Attribute name ELEV What it means LAT LOC LON NAME Shape TYPE Close the table by clicking on the cross in the top right hand corner of the table. Turn off (untick) the Volcanoes layer and turn on (tick) the earthquake layer Quakes. Leave the Plates layer on. The next question will form the second part of your assessment for this task. When you have completed your answer, copy and paste it into the document you previously saved as GIS Map Assessment in your Geography folder. 5. Using the world map showing earthquakes and the PQE approach, describe the spatial distribution of earthquakes in relation to the plate boundaries. (3 marks) P - describe the general Pattern shown on the map Q - use appropriate examples and statistics to Quantify the pattern E - identifying any Exception to the general pattern 6

7 Interconnection is the relationship that exists between two or more geographic characteristics. If both characteristics occur in the same place then they have a strong interconnection. If one characteristic occurs but very few (or none) exist of the other characteristic then they have a weak interconnection. To describe an interconnection you should answer the following: - Describe the interconnection between the two characertistics using terms such as "strong" or "weak" - Use statistics to quantify the relationship between the two characteristics - Use appropriate examples to illustrate the interconnection - Identify any exceptions to the relationship. Leave the Quakes (earthquake) layer turned on. Turn off the Plates layer. Turn on the Volcanoes layer. The next question will form the third part of your assessment for this task. When you have completed your answer, copy and paste it into the document you previously saved as GIS Map Assessment in your Geography folder. 6. Describe the interconnection between earthquakes and volcanoes. (4 marks) Turn on the Plates layer. 7. What is the general relationship between plates, earthquakes and volcanoes? 8. Look at the map below (on the next page of this document) showing generalised plate movement. The red arrows indicate the direction of the plate movement. 7

8 a. Name two sets of plates, which are moving apart from each other (diverging). b. Looking at the GIS viewer map, are there more volcanoes or more earthquakes along divergent plate boundaries? c. Name two sets of plates, which are moving towards each other (converging). d. Looking at the GIS viewer map, are there more volcanoes or more earthquakes along convergent plate boundaries? Turn off the Quakes and Volcanoes layers. 8

9 In this last part of Task B you are going to query the database. This means you are going to obtain specific information from the database like asking it a question! This is done by asking the computer to restrict the information it looks at by entering rules (it is in fact called Boolean logic). The computer applies these rules to the database and then selects only the information, which satisfies all the rules (or parameters). You are going to find the locations of convergent, divergent and transform plate boundaries and for each type of plate boundary you will name landforms found there. These plate boundaries are found in the legend of the Landforms layer. To see the legend follow these instructions: Click on the arrowhead of the Landforms layer but do not turn the layer itself on. This will expand the Landform legend. By undertaking the query you will be only selecting one of these categories each time and then obtaining information from it. Each plate boundary type creates specific landforms. The layers turned on should be as follows: Plates, Country 2010 and Ocean. We will be using the Landforms layer but the task is easier if it is not visible i.e. not turned on. Query of Convergent Landforms Right click the Landforms layer and choose Query Layer. A window will open which is called the Query Builder. Under Field Name double click type. The word type should appear in the box near the bottom of the window. Click the = sign. Click on Get Unique Values. Double click on Convergent. This process is creating a query string (a statement or equation) in the query builder. It is asking the computer to look specifically for data which is of the type convergent i.e. shows landforms on convergent plate boundaries. Click OK. A table should appear in which are listed all the locations on the map which have landforms that have formed along convergent plate boundaries. Note: You can make the Name column wider if you cannot see the whole name. 9

10 9. a. Name three landforms, which have formed as a result of convergent activity. b. Using the world map showing your query, describe the general location of convergent landforms. Are they on plate boundaries? The edges of continents? The middle of land masses? Close the table. Turn the Quake (earthquake) layer on. Using the Snipping Tool (This tool is not part of the GIS viewer. To locate this tool go to: Start bottom left hand corner of your computer - All Programs, Accessories, Snipping Tool) make a copy of your map and save it as Convergent in your Geography folder. Turn the Quake (earthquake) layer off. Clear the map by right clicking on the Landforms layer and click Clear Selection. Query of Divergent Landforms Right click the Landforms layer and choose Query Layer. Under Field Name double click type. The word type should appear in the box near the bottom of the window. Click the = sign. Click on Get Unique Values. Double click on Divergent. Click OK. A table should appear in which are listed all the locations on the map which have landforms that have formed along divergent plate boundaries. 10

11 10. a. Name the two landforms given, which have formed as a result of divergent activity. b. Using the world map showing your query, describe the general location of divergent landforms. Are they on plate boundaries? The edges of continents? The middle of land masses? Close the table. Turn the Quake (earthquake) layer on. Using the Snipping Tool make a copy of your map and save it as Divergent in your Geography folder. Turn the Quake (earthquake) layer off. Clear the map by right clicking on the Landforms layer and click Clear Selection. Transform plate boundaries (sometimes referred to as conservative plate boundaries) A transform plate boundary is where plates slide past each other. Here land is neither created or destroyed. Perhaps the most famous transform plate boundary is California s San Andrea s fault. Query of Transform Landforms Right click the Landforms layer and choose Query Layer. Under Field Name double click type. The word type should appear in the box near the bottom of the window. Click the = sign. Click on Get Unique Values. Double click on Transform. Click OK. A table should appear in which are listed all the locations on the map, which have been formed along transform plate boundaries. 11. a. Name the landform which has been formed as a result of transform plate activity. 11

12 b. Using the world map showing your query, describe the location of the transform landform. Is it on a plate boundary? The edge of continents? The middle of land masses? Close the table. Turn the Quake (earthquake) layer on. Using the Snipping Tool make a copy of your map and save it as Transform in your Geography folder. Turn the Quake (earthquake) layer off. Clear the map by right clicking on the Landforms layer and click Clear Selection. The next question will form the fourth part of your assessment for this task. Open your GIS Map Assessment document from your Geography folder. Insert the three maps you have recently saved as Convergent, Divergent and Transform. Make sure the maps are clearly labelled. (3 marks) Using these three maps, complete the questions below. 12. a. Which type of plate boundary produced the least earthquakes? Use evidence from the map to support your answer. (1 mark) b. Which type of plate boundary produced the most earthquakes? Use evidence from the map to support your answer. (1 mark) Now copy and paste these answers into your GIS Map Assessment document directly below the three maps. Put your name on this document, save it and submit it to your teacher. The Andes and the Cascade Mountains were formed (and are still being formed) as a result of oceanic plates converging with continental plates. This special type of convergent plate boundary is called a subduction zone. Follow the directions below to create a query that will select both these mountain areas. This is an advanced query statement as only two specific things are being selected it is not a general query. For each mountain you wish to select you will need a complete query statement. The two query statements will also need to be joined with the OR operator. We want the computer to look for data files for either the Andes Mountains OR the Cascade Mountains this is why we use the OR command and not the AND command in this query statement. 12

13 Right click the Landforms layer and choose Query Layer. Under Field Name double click NAME. Select the = sign. Click on Get Unique Values. Double click on Andes Mountain Range. Select Or. Double click NAME. Select the = sign. Double click on Cascade Mountain Range. The statement you have created should now read: NAME = Andes Mountain Range Or NAME = Cascade Mountain Range. Click OK. Ensure the Landforms layer is turned off. A table should appear in which the Andes and Cascade Mountain Ranges are displayed. The location of the mountains is also displayed on the world map. Turn on the Volcanoes layer and then turn on the earthquake layer Quakes. Zoom in to the west coasts of North and South America where the Andes and Cascade Mountains (your query) have been displayed. 13. Describe the interconnection between Volcanoes and the subduction zone in South America. 14. Describe the interconnection between Earthquakes and the subduction zone in South America. The aim of the next task is to identify the capital cities located in the convergent landform area of the subduction zone. Turn on the City layer. We are now going to query the city layer to select the capital cities. Right click on the City layer and select Query Layer. Under Field Name double click CAPITAL. Select the = sign. From Get Unique Values double click Y and then OK. A table will open listing all the capital cities of the world. The capital cities are also displayed on the map. Using either the Zoom In tool or the Fixed Zoom In tool, zoom in to the west coast of South America. 13

14 If the table is in your way close it. Using the Identify Feature tool, click on the capital cities which are located in the convergent landform area of the subduction zone. 15. Using the information obtained from the Identify Feature tool, complete the table below. Ensure they are in fact located in the subduction zone zoom in to check. Name of capital city Country Population 16. Based on the work you have completed why do you think it is important to understand the geography of convergent plate boundaries? 17. Do you think it is important for government agencies to understand that plate movement and population are interconnected? Explain your answer. Extension Construct your own query to establish the five capital cities which lie within the divergent plate boundaries of the Mid Atlantic Ridge and the East African Rift Valley. 14

15 Part C Developing and testing two hypotheses (or theories) to understand the relationships between earthquake magnitude and date of event and their impact on people. In this part you will be exploring two variables associated with earthquakes and how they may affect the death toll that results. In the database or spread sheet which creates the Quake layer, there are 3172 earthquake records i.e. there are 3172 rows one for each earthquake. These entries represent earthquakes from 2150 B.C to In this data, the deaths resulting from these earthquakes ranges from 0 to 1,100,000. The earthquakes to be examined are those which resulted in a death toll of greater than or equal to 70,000. To find these, you must first conduct a query of the data. Clear previous queries by right clicking on the Landforms Layer and then select Clear Selection. Ensure the only layers turned on are Plates, Quakes (earthquakes), Country 2010 and Ocean. Right click on the Quakes layer and select Query Layer. Under Field Name double click on DEATH (you ll need to scroll down to find it). Click on the >= sign. Click in the box near the bottom of the Query Builder and type in (no commas). Click OK and then enlarge the table so you can see all its contents. Look at the table showing the Query Results. Click on the column header NAME to sort the data into alphabetical order. 1. a. Which country has experienced the most earthquakes with deaths greater than or equal to 70,000? Sort the YEAR data. b. Which continent has experienced the last three earthquakes causing deaths greater than or equal to 70,000? Reduce the size of the table but do not close it. Use either the Zoom In tool or the Fixed Zoom In tool to get a closer look at your query result. The blue dots show the locations of earthquakes. 15

16 2. Using the PQE approach, describe the spatial distribution of earthquakes that have resulted in greater than or equal to 70,000 deaths. P - describe the general Pattern shown on the map Q - use appropriate examples and statistics to Quantify the pattern E - identifying any Exception to the general pattern In Geography (and also in Science), often a theory or hypothesis is created before data is created. When there are two different variables it is important to think what the relationship might be between them prior to data collection. In this example, the variables to be compared with the high death toll are the magnitude of the earthquake (measured using the Richter Scale) and the year the earthquake occurred. Remember the point of creating a hypothesis is to either prove or disprove it. Disproving a hypothesis is equally as useful as proving one. Sometimes the data will not prove or disprove the hypothesis in this case the hypothesis is partially accepted. 3. For the variables below write a hypothesis demonstrating what you believe the relationship is between the two variables. The first one has been partially completed to help you. a. Variables: magnitude and high death toll (complete the sentence) The relationship between magnitude and high death toll is that as the magnitude increases the death toll. b. Variables: year of event and high death toll Click on the MAG field to sort it. This column is the Richter Scale reading for each earthquake. 4. a. What is the highest and lowest magnitude recorded here? b. Describe the general relationship between MAG and DEATH? Explain your answer. Hint: you can drag the MAG field (or column) beside the DEATH field so it will be easier to compare. 16

17 Click on the YEAR field to sort it. 5. a. Describe the general relationship between Year and DEATH. b. What might explain this relationship? Turn off the Quake layer. Your earthquake data query will still be selected and highlighted. Zoom into the selected earthquakes in Asia. 6. What can you say about the location of these killer events and their relationship to plate boundaries? 7. Look at the data you have collected to assess your hypothesis looking at magnitude and high death toll. Think about how the data relates to the hypothesis. a. Complete the following statement by deleting the incorrect options: Based on the data I collected I accept / reject / partially accept* the hypothesis comparing magnitude with high death toll. *delete as necessary b. Explain your answer. 8. Look at the data you have collected to assess your hypothesis looking at year of event and high death toll. Think about how the data relates to the hypothesis. a. Complete the following statement by deleting the incorrect options: Based on the data I collected I accept / reject / partially accept* the hypothesis comparing year of event with high death toll. *delete as necessary 17

18 b. Explain your answer. Extension Construct your own query to establish the earthquake events which resulted in a tsunami and deaths greater than or equal to 70,000. Hint: think carefully about the logic term you use to join the two searches. a. Complete the table below with the results. Earthquakes which resulted in a tsunami and greater than or equal to 70,000 deaths. Year Country Number of deaths b. Describe the spatial distribution of the results using the PQE approach. 18