The first module of our Special Topics in Archaeology course begins a three module project using remotely sensed data to locate Mayan pyramids in dense jungle terrain. As seen above, we produced three rasters depicting a single area in El Mirador, Guatemala, with the intent of noting any noticeable characteristics in the raster data indicating the presence of the La Danta pyramid. The Landsat 7 data were downloaded from the USGS Earth Explorer website (http://earthexplorer.usgs.gov). The first raster we looked at was composed solely of Landsat 7's band 8. This panchromatic (sensitive to visible light) band is of a higher resolution than the other bands (15 meter versus 30 meter), yet the La Danta pyramid is far from obvious in the raster. We next combined Landsat 7 bands 1, 2 and 3 into a composite raster to replicate natural colors. Again, the pyramid does not show up as terribly obvious. The finally raster produced this module was another 3 band composite, only this one utilized bands 2, 3 and 4 to create a false color raster showing near-infrared data (band 4) as red in the final image. While perhaps a slight improvement over the previous two rasters, I was still unable to clearly identify the pyramid in the false color raster.
In addition to the bands utilized in this module, Landsat 7 data include three additional bands of short-wave and thermal infrared remotely sensed data. Further raster composites are possible utilizing these bands for more analytical tasks in the infrared wavelengths. Perhaps these bands will draw out the La Danta pyramid more clearly in the next two modules.
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