NSC Lecture on Seeing Through the Forest: Lost Cities, Remote Sensing and LiDAR Applications in Archaeology

Dr. D. Kyle Latinis, Visiting Fellow at the Nalanda-Sriwijaya Centre (NSC), discussed the latest advances in remote sensing technology for archaeological research – LiDAR (Light Detection and Ranging). LiDAR is revolutionizing the study of ancient urban landscapes in Southeast Asia.

NALANDA-SRIWIJAYA CENTRE
Lecture: Seeing Through the Forest: Lost Cities, Remote Sensing and LiDAR Applications in Archaeology

Friday, 21 April 2017 – Dr. D. Kyle Latinis, Visiting Fellow at the Nalanda-Sriwijaya Centre (NSC), discussed the latest advances in remote sensing technology for archaeological research – LiDAR (Light Detection and Ranging). LiDAR is revolutionizing the study of ancient urban landscapes in Southeast Asia. It has significant impacts on sampling and methodological approaches. 

Dr Stephen Murphy from the Asian Civilisations Museum chairing the session with Dr D. Kyle Latinis, Visiting Fellow at the Nalanda-Sriwijaya Centre (Source: ISEAS – Yusof Ishak Institute)

The lecture, entitled “Seeing through the Forest: Lost Cities, Remote Sensing and LiDAR Applications in Archaeology,” was held at the ISEAS – Yusof Ishak Institute.  The lecture drew nearly 30 people, including diplomats, government officials, academics, museum curators, students, and members of the public.  Those who attended the lecture were provided LiDAR image handouts which encouraged them to identify ancient structures. 

LiDAR technology allows researchers to digitally peel away forest canopies as part of an aerial scan. The laser scan produces a 3-D point cloud. Vegetative cover can be digitally removed. A topography of the landscape remains. The application is ideal for areas with heavy biomass.

Structures and landscape modifications such as ancient temples, roads, walls, water features and household mounds can be readily identified. Gridded patterns indicate entire neighbourhoods and agricultural systems. Entire urban landscapes can be revealed with sub-meter accuracy.

Dr D. Kyle Latinis giving his lecture on LiDAR (Source: ISEAS – Yusof Ishak Institute)

However, LiDAR cannot determine how old the features are. Archaeological survey and testing are still required to determine age. Interestingly, certain patterns may be particular to a particular cultures and time periods. Once programmed into the analytical software, pattern recognition becomes a very powerful tool to help unravel entire landscape and settlement histories.

Although currently very expensive, Latinis argues that the technology is cost-effective in the long-term. What would normally take years and decades to achieve on foot with large teams, can now be done in hours and days by a small crew with increased accuracy and precision. Furthermore, the technology allows one to see large features in entirety that would be missed on foot; such as massive rock quarries, planned neighbourhoods, agricultural systems, and complex infrastructure. Knowing the larger picture also allows developers and planners to make better and more cost-effective decisions vis-à-vis heritage and environmental conservation concerns.

Latinis discussed two recent NSC projects in Cambodia as case studies: the 9th century Angkorian capital of Mahendraparvata at Phnom Kulen and the 10th century Angkorian capital at Koh Ker. At Mahendraparvata, Latinis showcased how a simple LiDAR map enabled him to calculate the cubic meters of earth moved to build the ancient palace. The results provide proxy variables to estimate labour, time, capital, management levels and organization. This also allows us to consider power, wealth, social complexity, and other factors.  These can be compared to other urban complexes in different places and times for a variety of analytical purposes. For the Koh Ker site, Latinis demonstrated how LiDAR data allowed the team to identify and investigate a potential residential neighbourhood. Similar volumetric analyses will be applied. Furthermore, the neighbourhoods and complex patterns at Koh Ker are being used to test pattern recognition capabilities.

Participants at the lecture (Source: ISEAS – Yusof Ishak Institute)

LiDAR’s potential role in heritage management was discussed during the Q&A.  Latinis recommended that because LiDAR is likely to increase the number of new potential sites for a vast area in a short period of time, governments should consider investing in LiDAR, ground truthing, and obtain local feedback as part of a proactive zoning and heritage management initiative.  In terms of practical applications, LiDAR can also be used to periodically to track changes (check on flood damage, visualize tourist impact). 

Report by Foo Shu Tieng