TITLE:
The Advanced Hydraulic City Structure of the Royal City of Angkor Thom and Vicinity Revealed through a High-Resolution Red Relief Image Map
AUTHORS:
Shimoda Ichita, Haraguchi Tsuyoshi, Chiba Tatsuro, Shimoda Mariko
KEYWORDS:
Airborne Laser Scanning, Visualization, Urbanism, Water Management, Khmer
JOURNAL NAME:
Archaeological Discovery,
Vol.4 No.1,
January
5,
2016
ABSTRACT: Numerical topographic data acquired through airborne laser scanning (LiDAR) performed at the
Angkor Archaeological Park in Cambodia in April 2012 has revealed a large number of heretofore
obscured water channels and ponds (Evans et al., 2013). Using this data, a high-resolution red relief
image map (RRIM) was created of areas inside and outside the moated royal capital of Angkor
Thom built during the latter half of the 12th century. The land around Angkor Thom is extensively
covered by tropical jungle which has relatively well preserved the original urban structures and
middle/post-Angkorian period modifications and renovations by escaping human-induced surface
alteration except for the tourism-related infrastructure and renovations from the 20th century
onward. The RRIM provided a new visualization method of localizing, minute topographical
changes in regions with large undulations over a wide area. It has proved to be effective in mapping,
on a single wide-area map, the numerous buried remains that exist as comparable height
differences or minute undulations measuring less than 1 meter in height, and provides a unique
aerial view of their widespread distribution. Based on the RRIM map, past archaeological studies
were referenced to reconstruct the layout of the water channel network system. Past studies revealed
that a large number of ponds had been dug inside Angkor Thom. The RRIM expanded the
investigation and revealed the existence of many ponds outside the royal capital indicating that a
residential community had flourished outside the moat-surrounded capital city. This paper was
discussed the functional aspects of the water channel network and ponds that utilized the gentle
gradient of the natural land to overcome the climatic induced environmental changes that were
characterized by an extreme divide between the rainy and dry seasons.