Look, but Don’t Touch

Remote Sensing in Archaeology

4 min readNov 14, 2020

Dr. Chet Walker is operating magnetic survey equipment across the prairie with the mound at Town Creek Indian Mound visable. — A magnetic survey at Town Creek Indian Mound

Distance Archaeology

The field of archaeology has moved beyond its origins of digging large pits in search of fancy objects to fill museums and private collections. Archaeologists have long realized that careful, scientific research can yield an infinite amount of information that is limited only by our ability to understand and our technology. Excavations are unavoidably destructive and archaeologists are increasingly turning to other technologies and leaving the trowels at home. Collectively known as remote sensing, various tools are used to gather information about a site or artifact from a distance without disturbing or destroying the soil. Old and new technologies can direct excavation efforts by providing information from below the surface about the best places to dig. The more information on hand, the more time, money, and resources can be saved before the digging starts.

Remote sensing is a way of collecting data from an archaeological site without touching anything. The oldest and most accessible form of remote sensing is photography. Photographic images of a site, excavation, region, or artifact can showcase details that may be missed at first glance and preserve information that can be reviewed later. Cameras have long been attached to airplanes, kites, balloons, and drones to capture aerial photos which archaeologists can use to identify possible locations of sites. Multiple aerial photographs of a site can be fitted together to create a larger visual representation without sacrificing the quality of the image. Satellite images taken from space have been around since the Cold War and declassified images can help archaeologists understand some landscapes before the rapid pace of industrialization. In addition, publicly available satellite resources, such as Google Earth, can be used to identify sites in very remote places.

Some remote sensing technologies can detect objects and relay the information in a way that can be interpreted by archaeologists. Lidar (Light detection and ranging, also LiDAR) is a technique that sends rapid pulses of a laser from a plane to the ground. The light bounces off the surface and back to a plane or drone. The amount of time it takes for the light to travel is recorded and archaeological features become visible. Lidar is particularly effective in heavily wooded areas because the light traveling though the tree canopy can be accounted for when the data is analyzed. GPR (Ground Penetrating Radar) is a device that archaeologists roll across a site in an even grid pattern. Radio pulses from the equipment echo back to the surface and information about the depth and time of the pulses are recorded. Eventually, a rough, three-dimensional image of the soil can help archaeologists pick where to dig. Similarly, a magnetic survey can pick up fired clay, iron and other features below the earth’s surface that are different from the earth’s magnetic field. These are among the many forms of remote sensing that allow archaeologists to preserve the past for the future.

Technology in Your Life

What technologies do you use on a daily basis and what actives can you do with these technologies?
Did these technologies replace older tools?
What activities do you think could be replaced by new technologies in the future?
How do activities change when new technologies are introduced?

Each Tool Has a Task

Imagine you are an archaeologist. For each problem, pick a remote sensing technology that will help you complete your research project. The answers are provided at the bottom of the page.