Uncovering archaeological landscapes at Angkor using lidar

Abstract

Previous archaeological mapping work on the successive medieval capitals of the Khmer Empire located at Angkor, in northwest Cambodia (∼9th to 15th centuries in the Common Era, C.E.), has identified it as the largest settlement complex of the preindustrial world, and yet crucial areas have remained unmapped, in particular the ceremonial centers and their surroundings, where dense forest obscures the traces of the civilization that typically remain in evidence in surface topography. Here we describe the use of airborne laser scanning (lidar) technology to create high-precision digital elevation models of the ground surface beneath the vegetation cover. We identify an entire, previously undocumented, formally planned urban landscape into which the major temples such as Angkor Wat were integrated. Beyond these newly identified urban landscapes, the lidar data reveal anthropogenic changes to the landscape on a vast scale and lend further weight to an emerging consensus that infrastructural complexity, unsustainable modes of subsistence, and climate variation were crucial factors in the decline of the classical Khmer civilization.Southeast Asia | urbanism | sustainability | resilience | water management

Now You See It… Now You Don’t: Understanding Airborne Mapping LiDAR Collection and Data Product Generation for Archaeological Research in Mesoamerica

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3D Point Clouds in Archaeology: Advances in Acquisition, Processing and Knowledge Integration Applied to Quasi-Planar Objects

“…It is a powerful tool to analyse past settlement and landscape modification at a large scale. Use cases such as in [20][21][22][23] helped remove preconceptions about settlements size, scale, and complexity by providing a complete view of the topography and alterations to the environment, but while it provided new research and analysis directions, the LiDAR data did not leverage 3D point clouds considered too heavy and too raw to provide a source of information.…”

Airborne Laserscanning in Archaeology: Maturing Methods and Democratizing Applications

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