Seismo-Acoustic Responses of Explosions, Mining and Machining in Different Geological Materials: A Parametric Study of Different Emplacements and Different Energy Depositions.
Date: 4/26/2019
Time: 06:00 PM
Room: Fifth Avenue
We have performed quasi-3D high-resolution numerical simulations of surface and underground explosions using LLNL’s massively parallel eulerian hydrocode GEODYN to assess the impact of parameters such as, first, yield from explosion sources and noise sources from mining and industrial machining; second, height & depth of burst (HOB and DOB, respectively) of explosions versus mining and industrial machining emplacements; and, third, geological material on the overall source resulting overpressure in air and seismic motions at distance. The material properties span a large spectrum from hard rock, such as granite with low porosity, limestone, sandstone, tuff, salt, and very weak material, such as dry and wet alluvium. Arrival times to surface station are determined by the shock wave propagation and the coupling of ground motion. We show that for explosion overpressures and peak velocities due to the same yield at the same scaled HOB/DOB are functionally very similar regardless the geological fabric and therefore the response can be scaled. Moreover, the impulse is calculated by integrating the initial positive pressure time-history. It was found that the functional form of the impulse as a function of scaled HOB/DOB is also consistent for emplacements above ground, at ground level and down to depths where cratering occurs regardless for all geological materials even though the material properties show drastic geomechanical variations. While the current study used numerical simulation from idealized settings, additional factors can complicate observed seismo-acoustic signals and bias the amplitudes and subsequent source characteristics signatures and emplacements estimates. For example, we show that the emplacement geological uncertainties strongly impact the seismo-acoustic amplitudes and could impede source and source parameters identification.
Presenting Author: Souheil M. Ezzedine
Authors
Souheil M Ezzedine ezzedine1@llnl.gov Lawrence Livermore National Laboratory, Livermore, California, United States Presenting Author
Corresponding Author
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Oleg Y Vorobiev vorobiev1@llnl.gov Lawrence Livermore National Laboratory, Livermore, California, United States |
Madonna K Yoder yoder6@llnl.gov Lawrence Livermore National Laboratory, Livermore, California, United States |
Arthur J Rodgers rodgers7@llnl.gov Lawrence Livermore National Laboratory, Livermore, California, United States |
Tarabay H Antoun antoun1@llnl.gov Lawrence Livermore National Laboratory, Livermore, California, United States |
William R Walter walter5@llnl.gov Lawrence Livermore National Laboratory, Livermore, California, United States |
Seismo-Acoustic Responses of Explosions, Mining and Machining in Different Geological Materials: A Parametric Study of Different Emplacements and Different Energy Depositions.
Category
Non-traditional Application of Seismo-acoustics for Non-traditional Monitoring