WETMAAP Technique 2
Lake Pontchartrain - Martello Castle Element 1

Technique 2: Manual GIS
Element 1: Making Feature Overlays

Materials:

        1:24,000 USGS Martello Castle Quadrangle

        (3) 11"x 17" clear film overlay

        drafting tape

        Colored marker pens: Red, blue, black

Exercise:

1. Use 1:24,000 scale USGS Martello Castle Quadrangle

2. Use clear film 11"x 17"overlay (large)

3. Tape clear film overlay on top of 1:24,000 scale map. Tape at the top edge.

4. Use the red pen to make four "corner marks" (tick mark ^) on the overlay, one at each corner of the study site.

5. Trace the shorelines of the Mississippi River Gulf Outlet (MRGO) in Red on the overlay.

6. At the bottom of the overlay (in red) draw a short horizontal line and label beside it "MRGO."

Hint: Use of a symbol with a short description beside it is a "key," or means of identifying selected features.

7. Remove the "MRGO" overlay.

8. Use a second 11"x 17"clear film overlay

9. Tape clear film overlay on top of 1:24,000 scale map. Tape at top edge.

10. Use the Blue pen

11. Use the Blue pen to make four "corner marks" (tick mark) on the overlay, one at each corner of the study site.

12. Trace only the pipelines in Blue on the overlay.

13. At the bottom (in blue) draw a short horizontal line the same length as the red line and label it "Pipelines."

14. Remove the "Pipelines" overlay

15. Use the third 11" x 17" clear film overlay

16. Tape clear film overlay on top of the 1:24,000 scale map. Tape the top edge.

17. Use the Black pen

18. Use the Black pen to make four "corner marks" (tick mark ^) on the overlay, one at each corner of the study site

19. Make a dot for each building (camp) and for Martello Castle in black on the overlay.

20. Label the dot that is Martello Castle.

21. At the bottom (in black) make a dot and label it "Buildings." Do not remove this overlay.

Hint: Combining several single "key" items creates a "legend." Every map should have a legend

22. Tape the "MRGO" and "Pipelines" overlays one on top of each other, over the "Buildings" overlay. Use the four corner marks to line-up (‘register’) the overlays on top of each other.

Hint: Tape one overlay at the bottom edge and the other overlay at the left or right edge. By attaching the overlays at opposite edges, you can flip the overlays up and down in various alignment. You have created a    manual GIS.