Here is a relief map of Guam. It resulted from the use of the "surface" command in openSCAD.

Data was taken from the file 10n120e_20101117_gmted_mea075.tif, a part of the USGS GMTED2010 data set available from earth explorer.

http://earthexplorer.usgs.gov/

The portion around Guam was converted to an array, (210x240), of real numbers with a fortran program.

OpenSCAD code and the array of numbers are included.