Geo-reference Map Generation Process

Using Google Earth

The software allows us to generate images and coordinates of determined area.

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The purpose of determining the Magnetic Declination is to identify the True North for the site. Note that a positive declination is east, while a negative declination is west.
Run Google Earth
Type Lake Okeechobee in the search box then select "Enter" key on keyboard.
On the toolbar of Google Earth, left mouse click on Tools/Options/Apply/OK. 246645222 Figure 1 and 246645222 Figure 2 show this process.
Add a temporary placemark ( see 246645222 Figure 3) to get coordinate of the placemark
Open USGS Web Calculator: http://ngdc.noaa.gov/geomag-web/ ( see 246645222 Figure 4).
Copy and paste coordinates of the placemark into the USGS web calculator. Note that select S/N and W/E accurately (see 246645222 Figure 5 ) then left mouse click on Calculate button.
Result of Magnetic Declination is displayed in 246645222 Figure 6.
Go back the Google Earth, enter the Magnetic Declination 6.26^oW (W mean that the Declination here is negative) on the heading of the placemark. (see 246645222 Figure 7) then left mouse click the OK button. We will see that the background image on Google Earth will rotate from the west to the east with an angle 6.26^o.
After the background image points the true north correctly. Now we can delete the temporary placemark by right mouse click on placemark then select Delete option.

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On toolbar of Google Earth, left mouse click on Tools/Options/Apply/OK. (See 246645222 Figure 8).
Add placemark as names UL and LR

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Figure 12 Choosing Premium resolution.

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