More and more archaeologists who once relied on shovels and surveys now regularly collect data with digital sensors and use computer-based management systems to carry out complex analyses. Geographic information systems (GIS) and geographic information science (GISc), satellite remote sensing, aerial and close-range photography, terrestrial and aerial Light Detection and Ranging (LiDAR), near-surface geophysics, and a wide array of visualization schemes designed to integrate and display data from multiple platforms are now integral to every stage of archaeological investigation, interpretation, and reporting. Even though these methods are an increasing part of archaeological research worldwide, there have been few conferences, meetings, or workshops dedicated to sharing methods and applications in digital archaeology in North America or even in the Western Hemisphere, with the exception of a few special sessions in regional or general archaeological conferences. This deficit is particularly striking in comparison with the situation in Europe, where several societies dedicated to archaeological geomatics regularly hold both continental and regional meetings.

Medium-scale archaeological phenomena (large settlements, landscape features and infrastructural systems, road networks, etc.) pose significant challenges to archaeological documentation. Traditionally, such features are mapped either schematically or via labor-intensive (or otherwise costly) high-resolution methods. The advent of inexpensive, packable unmanned aerial vehicles (UAVs) and lighter-than-air platforms, combined with increasingly sophisticated photogrammetric and mobile geographic information system (GIS) software systems, presents opportunities for improving on these compromises. Here, we present results from test flights and photogrammetric mapping using UAVs and a meteorological balloon, combined with mobile GIS-based attribute registry of architectonic features at a large, complex colonial planned settlement (Mawchu Llacta de Tuti) in highland colonial Peru. First, the operating parameters of UAVs are presented, as well as the imagery capture and photogrammetric processing work flows. Second, we provide an overview of the tablet-based mobile GIS system used to digitize a site plan (based on the imagery from the UAV) and register architectural attributes from each building. The results from initial testing suggest that in the near future, such combined close-range photogrammetry and mobile GIS-based systems will significantly enhance and expedite high-resolution data registry of a wide range of archaeological features, sites, and landscapes.

Archaeologists from the Center for American Archeology (CAA) in Kampsville, Illinois, are engaged in a program to test the potential for ground-penetrating radar (GPR) and electrical resistance tomography (ERT) to effectively document the internal structure of a variety of Middle (ca.2200–1550 B.P.) and Late Woodland (ca.1550–950 B.P.) mounds in the Lower Illinois River Valley (LIV). This project, embedded within ongoing CAA regional research efforts and the Arizona State University Kampsville Field School, demonstrates that both GPR and ERT permit the identification and measurement of significant internal mound structures. Key structural elements can be confidently identified in the geophysical data from the five test mounds, and excavation results can be conclusively linked with results of excavation in mounds that have been tested. This study opens the way for the development of a set of procedures for a regional research initiative in the LIV to understand structural variation between Middle and Late Woodland mounds using ground-based remote sensing methods as a primary source of data and thus minimizing invasive and destructive investigation techniques.

In large arid floodplains, like that of southern Iraq, the rise of the water table associated with irrigation can result in surface salt concentrations over the remains of subsurface architecture. These traces are visible only from the air but are sometimes captured by commercially available submeter pixel imagery. This article describes the methods used and some of the results of a project using QuickBird, WorldView-1, and WorldView-2 imagery to investigate settlement systems in southern Mesopotamia dating between the fourth and first millennia B.C. Following a discussion of methods used to better predict which images of which sites will produce the desired results, a brief exploration of key anthropological questions that these data allow us now to ask will be presented.

Remote sensing applications are increasingly common in archaeology but they often focus on high resolution imagery and direct archaeological site detection. Moderate spatial resolution remote sensing instruments, which have (near) daily repeat intervals, but contain less detailed spectral and spatial information, have been employed much less frequently in archaeology. However, moderate remote sensing data offer distinct advantages for archaeological research as they can be used to relate archaeological, ecological, and climactic data at vast spatial scales. To show this potential, we use moderate remote sensing data to examine the impact of landscape heterogeneity on the spread of indigenous maize horticulture in the northern Great Lakes during Late Precontact (ca. AD 1200-1600). Analyzing National Aeronautics and Space Administration (NASA) Moderate Resolution Imaging Spectroradiometer (MODIS) imagery, we identify differences in freeze/thaw cycles across inland lakes in Michigan, showing that some large inland lakes produce a microclimatic amelioration, possibly extending the growing season for prehistoric maize cultivation. Conducting geospatial analyses, we find that burial mounds and maize cultivation practices were associated preferentially with larger inland lakes with microclimates. We could not have found these dynamic interrelationships between microclimates, burial mounds, and maize cultivation if not for both the frequent temporal imaging and large spatial coverage provided by moderate resolution remote sensing imagery.

The use of airborne LiDAR (Light Detection and Ranging) in western Belize, Central America, has revolutionized our understanding of the spatial dynamics of the ancient Maya. This technology has enabled researchers to successfully demonstrate the large-scale human modifications made to the ancient tropical landscape, providing insight on broader regional settlement. Before the advent of this laser-based technology, heavily forested cover prevented full coverage and documentation of Maya sites. Mayanists could not fully recover or document the extent of ancient occupation and could never be sure how representative their mapped and excavated samples were relative to ancient settlement. Employing LiDAR in tropical and subtropical environments, like that of the Maya, effectively provides ground, as well as forest cover information, leading to a much fuller documentation of the complexities involved in the ancient human-nature interface. Airborne LiDAR was first flown over a 200 km2 area of the archaeological site of Caracol, Belize, in April 2009. In April and May 2013 an additional 1,057 km2 were flown with LiDAR, permitting the contextualization of the city of Caracol within its broader region and polity. The use of this technology has transformed our understanding of regional archaeology in the Maya area.

With the ever expanding quantity of high-resolution aerial and satellite imagery available to archaeologists, numerous researchers have sought to address this “big data” challenge by developing automated methods to aid in the discovery and mapping of archaeological sites and features. This paper reviews several notable efforts to create automated discovery tools, including both spectral and object-based approaches, and highlights the difficulties these projects have encountered. Arguing instead for the critically important role of a human analyst in archaeological discovery, I illustrate interim results of an ongoing project that utilizes CORONA satellite imagery to document previously unknown sites in a 300,000 km2 study area in the northern Fertile Crescent. The project is based on what I term “brute force” methods, relying on systematic exploration of imagery by trained analysts, and has now successfully created a database of more than 14,000 sites, some 10,000 of which are previously undocumented. Results of the project highlight the need for human intervention to make any archaeological discovery meaningful, suggesting that imagery analysis, like any act of archaeological investigation, requires an engaged, thoughtful and creative scholar.