Lidar is a remote sensing technology that allows archaeologists to gain a better understanding of the geographical features in an area without surveying on the ground. It is utilized by pulsing lasers from a plane or drone down to the earth, and registering the time they take to return (US Department of Commerce, NOAA 2019). This data, combined with information from GPS, can generate an extremely accurate and precise topographic model of the area. It is especially useful because it is able to see through the treeline to the forest floor, which is vital in dense forested areas that would otherwise be difficult to ground survey or analyze through satellite imagery (Renfrew and Bahn 2018).
One region where the technology has been applied with great success is South and Central America. These regions have sections of extremely dense forest, as well as very little information recorded about pre-Hispanic societies, forcing archaeologists and historians to take different approaches to information gathering. While some societies, like the Inca and Maya, are the subject of a decent amount of recorded knowledge, in most other less established societies there is very little documentation. Lidar has proved to be extremely useful in discovering more about societal organization, agriculture, and infrastructure in lesser-studied parts of South and Central America.
Figure 1. Map of lidar-analyzed site with outlines known and possible features picked up by lidar. Map created by Rivera-Collazo et al., 2021.
Researchers have celebrated the role of lidar in the examination of thus far under-studied areas in Latin America. One group used lidar imaging to examine areas of Puerto Rico for ancient indigenous architecture. While there is limited lidar data for the Caribbean, open-access datasets revealed large-scale architectural planning, including plazas, paths, and possible agricultural areas. The authors discuss the helpfulness of lidar for this area in particular, which is densely forested and therefore difficult to access by ground survey or satellite imagery (Rivera-Collazo, Rodríguez-Delgado, and Rodríguez-Miranda 2021). This research reinforces the need for more lidar coverage in forested areas of the world, as it provides archaeological information that is not readily available in other forms. Another researcher discussed the use of lidar in the Bolivian Amazon, a region where researchers previously had known very little about pre-Hispanic societies. It was used to penetrate the treeline and two pre-hispanic low-density urban sites were discovered (Prümers et al. 2022). This type of society is harder for researchers to investigate because of a lack of written documents and permanent infrastructure, but the use of lidar can enhance search efforts.
Figure 2. Topographical map created by lidar of the site Cotoca, a large settlement found in the Bolivian Amazon. Map created by Prümers et al. 2022.
Many researchers in South and Central America support the use of lidar to discover more about Latin American pre-hispanic societies. The frequency of dense forests in these regions combined with the lack of comprehensive records of Indigenous societies and activities pre-colonialism makes it an excellent candidate for the use of lidar technology for initial archaeological survey. Lidar still requires corroboration, however, so it is not a replacement of fieldwork, but it can be used to narrow down sites for ground survey and excavation.
Prümers, Heiko, Carla Jaimes Betancourt, José Iriarte, Mark Robinson, and Martin Schaich. 2022. “Lidar Reveals Pre-Hispanic Low-Density Urbanism in the Bolivian Amazon.” Nature 606 (7913): 325–28. https://doi.org/10.1038/s41586-022-04780-4.
Renfrew, Colin, and Paul G Bahn. 2018. Archaeology Essentials : Theories, Methods, Practice with 303 Illustrations. London: Thames & Hudson Ltd.
Rivera-Collazo, Isabel, Eric Rodríguez-Delgado, and Marisol Rodríguez-Miranda. 2021. “Lidar Inspection for Indigenous Architecture at Caguana Ceremonial Complex, Borikén.” Latin American Antiquity 33 (1): 205–11. https://doi.org/10.1017/laq.2021.86.
US Department of Commerce, National Oceanic and Atmospheric Administration. 2019. “What Is LIDAR?” Noaa.gov. 2019. https://oceanservice.noaa.gov/facts/lidar.html.
Lost cities of the Amazon discovered from the air; https://www.smithsonianmag.com/science-nature/lost-cities-of-the-amazon-discovered-from-the-air-180980142/
Lidar reveals oldest and biggest Maya structure yet found; https://www.sciencenews.org/article/lidar-reveals-oldest-biggest-ancient-maya-structure-found-mexico
What are some of the limitations of Lidar? How can other archaeological techniques help us to supplement these limitations?