Spare

In any step, click the Show me link to reveal extra information. Click on images to see an enlarged image on its own page. If you prefer a printout of the full set of instructions for this part, choose Print from the File menu.

Step 1 - Download and Launch GeoMapApp Software Application

  1. Open the GeoMapApp homepage in a new window.

    2. Geomapapp home download links
    • From the Download Links panel on the left, click the link for your computer's operating system.
    • On the Web page that comes up for your computer, scroll to the bottom of the page, read the terms of distribution, and click AGREE to download the software.
  2. When the download is complete, locate the program file on your computer (wherever your downloads are stored) and double-click the GeoMapApp icon to start the program.
    • Click OK to select the default Mercator Base Map.
      GeoMapApp
    • You'll have an opportunity to create a directory or folder to store preferences for the program. Click Cancel to skip this step for your initial exploration.
  3. Once GeoMapApp is running, you'll see a map of Earth.

    When we look at world maps, we usually focus on the continents. Try to reverse your thinking and look at the ocean floor as the main feature of this map. As you visually explore the map, you may notice something quite odd...

    - Think about what you see: What do you think the different colors represent on this map? Do you have any ideas for how the map might have been made? Why do you think some continents appear twice?

    As recently as fifty years ago, many oceanographers believed that the bottom of the deep ocean was a flat, featureless surface. In the years during and after WWII, researchers like Harry Hess and others began experimenting with new SONAR technologies and discovered that the ocean depths contained many more topographic features than previously believed, including guyots, mountain ranges, and canyons.

    One researcher in particular deserves mention here. Marie Tharp began her career in the 1950s by drawing ocean floor maps from data collected by colleagues since women were not allowed on board ships until the 1960's. Her detailed maps provided clear evidence that the ocean bottom was not a wide open plane but rather a highly dramatic and varied terrain. Her contributions were fundamental in creating the first accurate picture that scientists had of the entire, rugged ocean floor, and helped ocean geologists in particular to lead the way in developing the theories of plate tectonics that are commonly accepted today.

    The GMRT map that you are seeing here is a compilation of research by hundreds of scientists during the past twenty years, using data collected from submersibles, ships, satellites, and even the space shuttle. It is a global digital elevation model of the ocean bottom mapped to a resolution of about 100 meters. GeoMapApp is able to view higher-resolution bathymetry data for specific areas that the user selects, as we will see in Part 2 of this activity.

  4. If you prefer, you can launch GeoMapApp directly from the Internet using Java Web Start. To do this, use the "here" link instead of the Download Links. Click on the question mark if you need help using Java Web Start.

Step 2 – Become Familiar With Basic Tools and Features of GeoMapApp

  1. Zoom in and out.
    2. magnify and demagnify buttons

    To zoom in on the map, click the magnifying glass with a plus sign in the toolbar then click on the location you want to enlarge. Use the magnifying glass with the minus sign to zoom out.

  2. Read the cursor location.
    3. Location of LatLong values

    Move your cursor across the map image and notice the changing values at the top of the map. These values show your cursor's location as a set of latitude and longitude coordinates. The longitude value (E or W) tells how far east or west of the prime meridian the location is. The latitude value (N or S) tells how far north or south of the equator the location is.

  3. Display a distance scale.

    4. Access the Overlays drop-down menu and select Distance Scale to turn on a distance scale.

    A NOTE ABOUT SCALES: On rectangular maps of our round planet, distance scales change with latitude. Scales in GeoMapApp only apply to the latitude where they are displayed. To see a distance scale for other latitudes, click the arrows at the side or bottom of the window to scroll the map: the map image will "slide" beneath the stationary scale and the scale will adjust to show accurate distances at whatever latitude it is displayed.

Step2 was added from Seafloor chapter

Step 3 – Locate the Galapagos Discovery Site

  1. Choose Datasets > Oceanic Hydrothermal Vents > Global Vent Distribution - InterRidge.

  2. Examine the distribution of oceanic hydrothermal vents around the world and look for patterns. How are the vents distributed?
    3. [thumbnail XXXXX 550] Insert a screenshot showing the vents on the map.
    The vent pattern seems to follow the coasts or be in the middle of the ocean floor. Vents appear to be located along plate boundaries.
  3. Look at the table at the bottom of the map.
    • You will need to move the table scroll bar horizontally to find the last column, labeled "citation". Move the "citation" column by clicking on the heading and dragging it next to the first column, "Name ID". Increase the width of the column by click on the right-hand column header divider and dragging to the right in order to read the full citation easily.
      • table for Galapagos vents - historic 1976
    • Sort the table to find all the sites near the Galapagos islands. Click once on the "Name ID" column header to sort the column alphabetically.
      • table alpha order and citations column moved
    • Scroll down the Name ID column until you find the sites named "Galapagos". The discovery site is labeled with a citation from 1976.
      • Galapagos Vents in the table
    • Click on the 1976 row in the table to highlight the discovery site and view its location on the global map. It will be highlighted on the map as a red dot.

    • Use the zoom tool to view the topography around the discovery site more closely. (you may have to reselect the appropriate site and check the plot/refresh box again)

Step 4 - Explore Images from the Galapagos Discovery Expeditions

  1. Download the spreadsheet file (Galapagos Discovery images (Excel 22kB Jan26 10)) and save the file to your desktop or to a location on your computer where you can find it easily.
  2. Use the File pulldown menu in GeoMapApp to import the spreadsheet file by selecting Import Table or Spreadsheet > From Excel-formatted (.xls) file, and browse to the location where you saved the file on your computer.

  3. After the table is imported, a Config window will appear. Reduce the symbol scale size percent to about 25, and adjust the color so you can distinguish the image locations from the vent locations in the main map window.

  4. Click OK and the locations of each of the seven images will be visible along the Galapagos rift. To view all of the image locations in the main map window, use the zoom tool in the Layer Manager window to adjust the view to the appropriate size.

  5. Click in any row in the data table to view a thumbnail of the image at a particular location.
    Part 1 Sample Product

    The arrows in the thumbnail viewer can be used to navigate through the list of images. As you switch between images, the location will be highlighted on the GeoMapApp window with a red dot. You can also increase the size of the thumbnail viewer to see more detail in the images.

    6. Warn about clicking the hotlinks in the table

  6. As you view the images, you can read a caption describing each image in the data table. Adjust the column width as you did in Step 3, number 3 to read the full caption.

Have users quit GeoMapApp