Detection of underground remains by remote sensing and geophysics

Shenmingpu Site, located in Henan Province in China, will be a part of the flooded areas during the magnificent South-North Water Transfer Project. According to previous records and land surface investigations, there may be some remains of underground burial so it is urgent to conduct a rescue excavation. Due to a large size of the site, it will cost high expense, substantial labor and time if we totally rely on traditional methods to detect them. Both remote sensing and geophysics are powerful tools for detecting surface and underground archaeological information, especially when they are combined. Remote sensing is useful in large-scale observation and detection when the remains are buried not very deep and make the soil or vegetation covering them different from the surrounding in physical or chemical appearance, which makes discrepant features appear on satellite imageries; geophysics can detect the underground structural compositions of small-scale areas based on the differences of density or resistivity. Multi-temporal CBERS-02 images were used to find the anomaly in the large protected area because the winter wheat planted above underground burial matured later than the surrounding. For the anomalous area on the images, two geophysical prospecting methods, the natural electric field method and high-density resistivity method, were conducted to validate the anomaly. After an in-situ excavation on the chosen anomalous ground, a group of graves including brick-chamber graves and shaft graves were unearthed.