Sensing Techniques

LiDAR (Light Detection and Ranging) is a remote sensing technology that uses laser pulses to measure distances between the sensor and objects on the Earth's surface. By emitting thousands of laser pulses per second and measuring the time it takes for each pulse to return after reflecting off an object, LiDAR creates precise, three-dimensional maps of terrain, vegetation, and built structures. It's particularly valuable in uncovering features hidden beneath dense forest canopies, such as ancient roads, buildings, or other archaeological sites. LiDAR is also widely used in applications like urban planning, autonomous vehicles, environmental monitoring, and disaster management, offering unmatched accuracy and detail in mapping and spatial analysis. See the USGS site for more details about this technology.

The use of False-Color Infrared Photography has increased the versatility of aerial photography and the development of photogrammetry allows the accurate mapping of both archaeological and geographical information. Recordings of thermographic and radar images complements photographic methods. Aerial Photography has proved to be one of the most successful methods of discovering archaeological sites. Large areas of ground can be covered quickly and the ground plan of a new site can be plotted from the photographs.

False-Color Infrared Photography is a technique of aerial photography used in archaeology especially in the Americas. Infrared film reacts to the varying water absorption qualities of different features, thus allowing changes in vegetation, the occurrence of buried features filled with disturbed soil and the presence of otherwise invisible roadways to be detected. The false color refers to the accentuation of specific features in red, pink, yellow, blue etc., which emphasize the contrasts but which are not the true colors of the features. Also, this technique often achieves greater resolution than conventional photography because the wavelengths are unaffected by atmospheric haze.