Visual Analysis of TerraSAR-X Backscatter Imagery for Archaeological Prospection

The use of satellite radar widens the possibilities of archaeological prospection extremely. The resolution of the available sensors however was quite limited until now and only the detection of huge upstanding monuments or cultural landscapes was possible. The launch of TerraSAR-X, a German radar satellite in 2007, however, now offers a resolution of up to 1 m, which is required as a minimum for detecting small archaeological remains. Whereas upstanding monuments are clearly identifiable, it was still uncertain, whether the used high-frequency X-band waves of TerraSAR-X could penetrate the soil and provide information on buried archaeology as well. This paper shows the results of two test sites in Syria and Italy. Both of them have in common that there are extensive surveys by ground-based geophysical surveys with magnetometry and ground-penetrating radar, which provide information on the buried archaeological remains. By a detailed visual comparison of these results with the TerraSAR-X data, we can prove that there is a slight penetration depth of a few decimetres.