Calderon, J, Barnes, R & Shilov, E 2025, 'Automatic multi-stage slow movement analysis for 
early warning monitoring systems for surface mining', in JJ Potter & J Wesseloo (eds), SSIM 2025: Fourth International Slope Stability in Mining Conference, Australian Centre for Geomechanics, Perth, https://doi.org/10.36487/ACG_repo/2535_50
(https://papers.acg.uwa.edu.au/p/2535_50_Calderon/)
Abstract: The development of processing techniques for radar monitoring data has significantly aided geotechnical practitioners in managing slope stability risks, especially when the radar system operates in real-time. Notable improvements have been made to address weather conditions and understand velocity behaviour to predict slope failure once the velocity measured on the slope becomes evident, using a real-time radar-based system.
Real-time radar monitoring using interferometry principles has limitations regarding measurable velocities. The maximum measurable velocity is typically constrained by phase ambiguity, mainly due to the radar frequency and the minimum time between scans. In the lower band, the minimum measurable velocity is limited by the instrument’s precision.
This work aims to establish a system that enables geotechnical practitioners to monitor the behaviour of lowvelocity ranges using different calculation periods for slow movement analysis, in a practical and automatic manner. This approach detects potential slope failures with minimal displacement rates, enhancing control effectiveness and operational continuity. Geotechnical engineers can inform potential slope stability issues significantly earlier compared to real-time systems for ground-based radars.
The new approach, called automatic multi-stage slow movement analysis, captures different ranges of lower band velocities. It automates data visualisation in parallel with real-time monitoring to detect displacement from natural slope deconfinement processes to initial indications of potential failures. This work details the pilot, methodology, and testing – using actual cases within BHP operations – highlighting the benefits of understanding initial slope deformations that are typically undetectable using real-time settings.

Keywords: monitoring automation, geotechnical monitoring system, slow movement analysis, slope performance, geotechnical monitoring, monitoring integration, ground-based radar, thresholds, interferometry