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Uncovering archaeological landscapes at Angkor using lidar
Damian H Evans1, Roland J Fletcher, Christophe Pottier
1University of Sydney, Sydney 2006, Australia. damian.evans@sydney.edu.au
Summary
Airborne lidar technology mapped previously hidden urban landscapes of the Khmer Empire in Cambodia. This reveals extensive infrastructure and provides new insights into the civilization's decline.
Area of Science:
- Archaeology
- Geospatial technology
- Southeast Asian Studies
Background:
- The medieval Khmer Empire (9th-15th centuries C.E.) established successive capitals at Angkor, Cambodia, forming the largest preindustrial settlement complex.
- Dense forest cover has historically obscured crucial ceremonial centers and surrounding areas, hindering comprehensive archaeological mapping.
- Previous mapping efforts were limited by vegetation, leaving significant portions of the urban landscape unexamined.
Observation:
- Airborne laser scanning (lidar) was employed to penetrate vegetation and generate high-precision digital elevation models of the ground surface.
- This technology allowed for the visualization of subtle topographic features indicative of past human activity.
- Lidar data provided unprecedented detail of the ground surface beneath dense forest canopy.
Findings:
- An entire, previously undocumented, formally planned urban landscape was identified and mapped.
- Major temples, including Angkor Wat, were found to be integrated within this newly revealed urban structure.
- Lidar data revealed extensive anthropogenic landscape modifications on a vast scale.
Implications:
- The findings support the emerging consensus on factors contributing to the decline of the classical Khmer civilization.
- Infrastructural complexity, unsustainable subsistence practices, and climate variations are highlighted as crucial elements in the civilization's collapse.
- This study demonstrates the transformative potential of lidar technology in uncovering hidden archaeological landscapes.
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