Qu, Q, Duan, J, Hoehn, K, Lin, X, Harpley, D & van de Werken, M 2026, 'Caving monitoring with integrated fibre-optic acoustic and strain sensing: a field experiment', in A van As, D Cumming-Potvin & J Wesseloo (eds), Caving 2026: Proceedings of the Sixth International  Conference on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth, pp. 1-12, https://doi.org/10.36487/ACG_repo/2645_48
(https://papers.acg.uwa.edu.au/p/2645_48_Qu/)
Abstract: Reliable monitoring of rock mass conditions is critical to ensuring safe and efficient resource extraction using the underground caving method, particularly under complex geological and mining conditions. Distributed fibre-optic sensing, with its spatially dense measurement capabilities, shows high potential for capturing detailed insights into rock mass deformation and fracturing activities, especially in the vertical direction. 
This paper presents a field experiment on monitoring rock mass fracturing and deformation propagation using an integrated distributed acoustic sensing (DAS) and distributed strain sensing (DSS) approach. Fibre-optic cables were installed in two surface boreholes and a surface trench, along with two geophones in each borehole for validation. Monitoring data were continuously acquired over a 10-month period, during which extensive seismic activity was recorded. The inferred rock mass deformation and fracturing activities are consistent with conventional understanding while revealing additional information that can complement geotechnical assessment. The trial also demonstrated the capability to detect low-magnitude events at specific depth intervals to support assessment of weak zone behaviour. 

Keywords: caving, distributed fibre-optic sensing, distributed acoustic sensing, distributed strain sensing, subsidence