GIS-Based Assessment of Salt Weathering Susceptibility in the Vicinity of Gangai Konda Cholapuram Temple, Tamil Nadu, India

Heritage stone structures in tropical and semi-arid environments are highly vulnerable to deterioration, which is caused by salt weathering, where crystallization leads to progressive material disintegration. This study presents a Geographic Information System (GIS)-based framework to map potential salt weathering susceptibility zones around Gangai Konda Cholapuram Temple, Ariyalur, Tamil Nadu, India.

The methodology integrates multiple geospatial datasets, including Sentinel-2 satellite imagery for surface condition analysis, NASA POWER climate data for temperature and atmospheric moisture, and Shuttle Radar Topography (SRTM) DEM for terrain analysis. Key environmental factors influencing salt weathering, including surface moisture, slope, elevation, and climate variations, were derived using GIS-based spatial analysis. All the thematic layers were standardized using min-max normalization to ensure comparability across the datasets.

A multi-criteria decision analysis (MCDA) approach using a weighted overlay technique was employed to generate a susceptibility map. The output classifies the study area into low-, moderate-, and high-susceptibility zones, found by the areas in favor of high moisture by the NDWI and based on salt accumulation.

This study gives a proxy-based modeling approach and does not include the laboratory confirmation of salt accumulation in those areas. However, the salt weathering risk map provides a preliminary decision for this kind of heritage place conservation.

The results demonstrate the effectiveness of integrating remote sensing and GIS-based MCDA for heritage vulnerability assessment and offer a great conservation plan for heritage places.