Integrated Non-Invasive Geospatial Technologies for Archaeological Prospection, Documentation, and Heritage Management: A Case Study of Dholavira, Gujarat

Dholavira, India’s second-largest Harappan site after Rakhigarhi, dating from 3000 to 1500 BCE, is renowned for its sophisticated water management system and has attracted significant archaeological interest since its discovery in 1968. Despite decades of conventional surveys, many structures remain unidentified, constraining spatial understanding of the site. This study develops a multi-sensor, multi-platform framework using active and passive datasets (optical, microwave, and LiDAR) from satellite, UAV, and ground-based sources to support improved documentation and analysis of archaeological features. Earth Observation (EO) datasets were processed to identify surface anomalies using multi-sensor analysis, while Synthetic Aperture Radar (SAR) data were used to delineate potential subsurface zones for subsequent GPR investigations. UAV-LiDAR data were utilized to enhance high-resolution 3D surface mapping of the site. Guided by satellite-derived anomalies, Ground-Penetrating Radar (GPR) surveys were conducted at selected locations to investigate subsurface features. The GPR results revealed shallow hyperbolic reflections and stratigraphic discontinuities up to ~1.5 m in depth, indicative of buried structures and disturbed ground conditions, with depth estimates derived using an assumed velocity model for dry sandy soils. Terrestrial Laser Scanning (TLS) enabled high-resolution three-dimensional reconstruction of excavated structures, showing close agreement with Archaeological Survey of India (ASI) records. The results demonstrate an effective and interpretable framework for archaeological prospection and multi-scale analysis, with future potential for integrating machine learning to advance systematic site analysis and digital heritage conservation.