# Improvements in Rock Mass Description for Stope Design by Geophysical and Geochemical Methods
## 7 Conclusions  
This paper provides an overview of a research project that aimed to improve stope design by addressing the needs of mining professionals and by developing promising techniques to improve the stope design process. According to the literature research, numerical modelling has become an important tool for stope design. Both continuum and discrete numerical methods are used to simulate jointed rock masses in the stope scale, mainly to optimize stope boundaries, the production schedule, and development activities.  
According to the survey within the industry, additional geotechnical data, software improvements, and integration of design into mine planning are identified as the most urgent topics for improvement. Fast data acquisition and automation of the design process were also highlighted. Respondents ranked cutoff grade and dilution as the most important parameters affecting stope design. The survey also indicated that sublevel stoping is the most used underground mining method (46% of respondents), followed by the cut-and-fill method (22%). Personal expertise, numerical methods, and empirical methods are all commonly used in stope design.  
Laser-induced breakdown spectrometry (LIBS) techniques were improved in order to be conduct measurements at the tunnel face and from core boxes to facilitate rapid decision-making and to provide new insights into the ore body. Point load test correlation with point load values predicted from LIBS data suggest that the LIBS signal can also be used for geometallurgical characterization.  
Ground-penetrating radar (GPR) studies were conducted to improve discontinuity characterization. This research indicated that ground-penetrating radar might be a valuable tool for the mapping and characterization of the location, size, geometry, and orientation of fractures, fracture zones, and other geological features. This in turn allows for a more optimized planning of the excavation of rock mass.  
The rapid photogrammetric method presented in this study offers efficient and accurate rock mass data acquisition, specifically tailored for stope design in underground excavations. Three presented approaches demonstrate the effectiveness in capturing detailed rock mass measurements such as the location and orientation of planar discontinuities inside tunnels and stopes.  
The techniques discussed in this paper already have many industrial applications. This study suggests that they have a strong potential to be adopted and further developed to serve for ore and rock mass characterization for stope design.  
Methodology, M.R., M.J., S.P., R.K., L.K., I.L. and J.L.; investigation, M.J., S.P., R.K., L.K. and I.L.; data curation, M.J., S.P., R.K. and I.L.; writing--original draft preparation, M.R., M.J., S.P., L.U., R.K., L.L. and J.L.; writing--review and editing, M.R., M.J., S.P., L.U., R.K., L.K., I.L. and J.L.; visualization, M.J., S.P., R.K. and I.L.; supervision, M.R. and J.L.; project administration, R.K.; funding acquisition, M.R., M.J., S.P., L.U., R.K., L.K. and J.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Academy of Finland grant number 319798 and the APC was funded by Aalto University School of Engineering.  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The authors kindly acknowledge the survey respondents for participating in the industrial survey. The international partners TU Delft, University of A Coruna, and University of Vigo are acknowledged for their good cooperation.  
The authors declare no conflict of interest.