Douglas-Brown, RE 2022, 'Monitoring and controls for sublevel caving in an anisotropic rock mass', in Y Potvin (ed.), Caving 2022: Proceedings of the Fifth International  Conference on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth, pp. 517-528, https://doi.org/10.36487/ACG_repo/2205_35
(https://papers.acg.uwa.edu.au/p/2205_35_Douglas-Brown/)
Abstract: Nickel West Venus orebody at Leinster, Western Australia is being mined using the sublevel caving (SLC) method. Learnings from the initial caving area, a small footprint SLC project within a high stress environment, are presented in this paper. The Venus orebody is situated within a heterogenous, anisotropic geological setting creating complexities for easy cave creation. Factoring in all geotechnical variables and potential risks, including, but not limited to, seismic response, dilution of ore, airgap creation, mud rush and surface subsidence impacting existing infrastructure. The first section of the Venus orebody SLC was created from three levels and established a means to calibrate the impacts of draw controls in an area with distinct changes in rock mass strength vertical to drawpoints. The draw strategy focused not only on maximising ore extraction but maintaining an adequate crown pillar due to the inferred subsidence zone and potential for interaction with surface infrastructure.  
Cave monitoring included seismic analysis, Elexon Smart Markers, fragmentation for bulking factor of blasted and caved material. Displacement of sigma one stress was inferred from seismic analysis, with expected energy release zones established. Cave height was tracked through a combination of all datasets, seismicity, geotechnical instrumentation, and height of draw (HOD). 

Keywords: sublevel caving, cave monitoring, draw control, seismicity, height of draw