SPATIAL - TEMPORAL RE-ENTRY PROTOCOL DEVELOPMENT BASED ON SEISMICITY PARAMETERS ANALYSIS IN

• Main Author: Ryano, Kevin
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/75336
• Institution: Institut Teknologi Bandung

Underground mining operations in hard rock formations have the potential to induce microseismic events. The seismicity level increases after major events and gradually decays over a specific time period. The heightened seismic activity poses risks to mining personnel and can even lead to damage to mining facilities within the mining field. Therefore, it is necessary to develop a protocol to restrict access to zones that are expected to be impacted by increased seismic activity during certain time intervals. This protocol is known as the re-entry protocol. In this study, the author conducted an analysis of seismicity parameters at the "UC" mining field to develop a spatial-temporal re-entry protocol. The DBSCAN clustering method was employed to identify spatial clusters of aftershock sequences related to the main events. Subsequently, the exclusion zone radius was calculated using the principle of sum of seismic moments, while the re-entry time was determined using the Omori-Utsu Law for each major event. From the analysis of 20 aftershock sequences spanning from January 2021 to October 2022, 11 sequences were selected that exhibited decay patterns in the seismicity level following the OmoriUtsu Law. These sequences were utilized as regression data to calculate empirical equations for the exclusion zone radius and re-entry time. The regression results demonstrated a significant relationship between the exclusion zone radius and reentry time, with coefficient of determination values of 0,65 and 0,57, respectively