Remote sensing in archaeology

Remote sensing techniques in archaeology are an increasingly important component of the technical and methodological tool set available in archaeological research. The use of remote sensing techniques allows archaeologists to uncover unique data that is unobtainable using traditional archaeological excavation techniques. Remote Sensing methods employed in the service of archaeological investigations include: Aerial, UAV and Satellite Imaging Aerial photography Multispectral and Hyperspectral Sensors Thermal Infrared Multispectral Scanner (TIMS) Color Infrared Film (CIR) Microwave Radar Satellite Imaging Laser altimeters or light detection and ranging (LIDAR) Synthetic Aperture Radar (SAR) INSAR - Interferometric SAR Ground-based geophysical methods such as Ground Penetrating Radar and Magnetometry are also used for archaeological imaging. Although these are sometimes classed as remote sensing, they are usually considered a separate discipline (see Geophysical survey (archaeology)). Satellite archaeology is an emerging field of archaeology that uses high resolution satellites with thermal and infrared capabilities to pinpoint potential sites of interest in the earth around a meter or so in depth. The infrared light used by these satellites have longer wavelengths than that of visible light and are therefore capable of penetrating the Earth's surface. The images are then taken and processed by an archaeologist who specializes in satellite remote sensing in order to find any subtle anomalies on the Earth's surface. Landscape features such as soil, vegetation, geology, and man-made structures of possible cultural interest have specific signatures that the multi-spectral satellites can help to identify. The satellites can then make a 3D image of the area to show if there are any man-made structures beneath soil and vegetation that can not be seen by the naked eye. Commercially available satellites have a .4m-90m resolution that make it possible to see most ancient sites and their associated features in such places as Egypt, Perù and Mexico.