Geophysical Prospection
Between 1999 and 2002, magnetometric prospecting was used for a subproject of the Bavarian State Department for the Preservation of Cultural Heritage and the Research Institute for the Preservation of Cultural Heritage of Shaanxi Province (at that time Center for Conservation of Cultural Heritage Xi'an). Magnetometry allows for the large-scale exploration of hidden sites. Archaeological structures such as wall remnants, fire pits, waste pits, ditches and wooden palisades are revealed as anomalies of the Earth's magnetic field. These small anomalies, recorded point by point in a 25 x 25 cm raster roughly 30 cm above the ground, can be pieced together in the laboratory using imaging methods to yield so-called magnetograms. The resulting images show the archaeological finds below ground - similar to the way X-ray images are used in the medical field.
Two archaeological sites in Shaanxi Province were geophysically measured and archaeologically interpreted using this method, avoiding the use of spades or shovels and without causing any damage: the palace of Emperor Qin Shihuang in Wazigang and the Han-era mint in Zhaolun. The resulting detailed archaeological site maps show a palace complex in Wazigang measuring more than 20 hectares, as well as the largest mint of Ancient China in Zhaolun.
Dr. Jörg Fassbinder (Bavarian State Department for the Preservation of Cultural Heritage)