Criteria for mining area postponed due relevant seismicity and its impact on caving propagation

Authors: Constanzo, H; Parraguez, R; Balboa, S; Bustamante, J Download Paper

Cite As:
Constanzo, H, Parraguez, R, Balboa, S & Bustamante, J 2024, 'Criteria for mining area postponed due relevant seismicity and its impact on caving propagation', in Daniel Johansson & Håkan Schunnesson (eds), MassMin 2024: Proceedings of the International Conference & Exhibition on Mass Mining, Luleå University of Technology, Luleå, pp. 613-628.



Abstract:
In 2016, it was decided to postpone mining area ahead front of Bloque-2 of Esmeralda Mine, due to the occurrence of relevant seismic events in the development area (exposure of personnel). This deferred area, named "Postponed Polygon (P.P.)", encompassed a total area of 8,800 m2 and would be re-evaluated in the future to demonstrate a favorable geomechanical environment for the resumption of development and mining operations in the P.P. The primary proposal to induce a change in the geomechanical conditions involves continuing to advance towards the south and east of the postponed area, with the aim of modifying stress conditions through the development of a cavity connected to the upper levels. The conditions of the polygon were corroborated through the assessment of several parameters such as: geomechanical damage survey (evaluation of the support system in galleries), seismic parameters related to the maximum recorded event and the evolution of the energy index, mining activity in terms of drawbell commissioning and extraction heights of Bloque-2. The integrated analysis of these data confirmed the favorable geomechanical conditions of the deferred sector, allowing the resumption of development and construction activities, progressing with the blasting of drawbells and the extraction of the postponed area to generate a uniform global cavity in Block-2.