One of the most highly touted competitive advantages of drones is their ability to conduct aerial site surveys that are more cost-effective and technically accurate than field surveys conducted on foot. Thousands of farmers and mining and construction company owners already swear by drones. But drones are also proving their worth identifying the ruins and artifacts of ancient civilizations and bringing to light hitherto unknown dimensions of their economic and cultural life.
In fact, the use of aerial vehicles to enhance archaeological field surveys is not entirely new. Archaeologists have deployed small airplanes, kites and balloons for decades to capture a bird’s-eye view of ancient sites. But drones can expand that view in myriad ways: with their superior maneuverability and advanced camera technology, they can explore areas of sites overlooked by earlier methods; they can also provide images – including 3-D images – with much higher resolution.
And through the use of AI-generated algorithms, a drone’s images can be fed into a computer and exposed to advanced analytics, dissected, and then compared with images collected from other sites, speeding and enhancing archaeological investigation and interpretation.
One artifact archaeologists typically look for is pottery – or the fragments thereof. In traditional site surveys, field inspectors may walk a recently plowed farmer’s field to detect if any fragments (known as potsherds) or other artifacts such as flint tools might have risen to the surface. These simple artifacts can reveal much about an ancient society – the way it farmed and prepared food and hunted, among other activities. “Pedestrian surveying” – as the age-old field technique is known – is tedious time-consuming work and despite their diligence even trained field inspectors can easily miss clues that might uncover important archaeological evidence, experts say. A single drone can survey an entire field in a single afternoon compared to the three days a paid six-man ground team might require – with the added cost of their food and lodging.
Not that drone surveying is perfect. Identifying potsherds through color and pixel imaging can still result in the identification of false positives – pieces of brick rather than pottery, for example – or false negatives, ruling out legitimate artifacts. And many drones have limited flight time and their use is restricted to open fields where aerial detection is not obstructed by trees, bushes and even weeds. But technology is rapidly improving, and with advanced sensors and better cameras. drones can often detect the likely presence of artifacts in previously obstructed or partially obstructed sites.
Another way archaeological drones are being used is to identify and document pre-modern rock sculptures and carvings that reflect the belief systems of ancient civilizations. This summer a dozen drone-qualified students at Embry-Riddle Aeronautical University embarked on a service-learning trip to New Mexico and Arizona to assist local archeologists to map 4,000-old cities in the two states. The extensive site mapping – aided by advanced sensor-imaging technology,including LIDAR – was impressive enough, but while there, the students also stumbled upon never before-seen “petroglyphs” carved into rocks on the property of a landowner in Tularosa, New Mexico. Some of the carvings depicted animals and scenes of everyday life but others displayed more abstract images with an esoteric meaning that archaeologists are still studying. Without the drones, these never-before-seen images might never have been discovered.
“The main purpose [of the trip] was to give students studying [drones] a real-world experience that meets a need,” Prof. Dan Macchiarella, the team’s leader, noted in a campus press release. “[Drones] bring a new aerial perspective to remote sensing. We can achieve levels of detail that exceed the best Google Earth images by a factor of over 25.”
Archaeologists working in other remote corners of the world have also begun deploying drones not only to discover and document potsherds and rock carvings but also to find new and promising areas to excavate. The Saudi Arabia-based Oriental Institute has begun surveying remote areas of eastern Jordan with remotely piloted drones in addition to small manned aircraft. Using 3D photogrammetry, the Institute’s team has been able to identify the rich flora and fauna of the region that existed 8,000 years ago – very different from the arid desert of today – as well as collapsed basalt structures that provide critical new evidence about the ways area residents lived and worked millennia ago.
The drones have another added benefit: while tracking the progress of the site over a period of years, they can monitor the inevitable looting of antiquities that occurs and alert Jordanian authorities to the need for stronger preservation efforts.
While drones cannot replace other archaeological methods completely – human surveyors still need to inspect sites and collect field samples, for example – their competitive advantage is undeniable. The Institute’s drones can create a comprehensive map of an entire archaeological site in a matter of hours (not days or even weeks) and come away with high-resolution images for analysis that even the best ground-level photography can’t match.
“We are in the middle of a revolution in aerial survey for archaeology,” says Yorke Rowan, senior research associate at the Institute