EGU24-9007, updated on 08 Mar 2024
https://doi.org/10.5194/egusphere-egu24-9007
EGU General Assembly 2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

A mechanical insight into the continuous chatter of a fault volume

Harsha Bhat1, Michelle Almakari1, Navid Kheirdast1, Carlos Villafuerte2, and Marion Thomas3
Harsha Bhat et al.
  • 1Ecole Normale Supérieure, Paris, France
  • 2Universidad Nacional Autónoma de México, Mexico City, Mexico
  • 3Sorbonne Université, Paris, France

In recent decades, there has been a proliferation of observations related to spatiotemporally intricate slip events occurring in fault systems. These events encompass a spectrum of transient energy releases, ranging from slow slip events to low-frequency earthquakes (LFEs) and tremors, in addition to the more familiar creep and fast ruptures. The prevailing focus in recent research has been to interpret these events by considering variations in frictional behavior along the fault plane.

However, it is crucial to acknowledge the inherent geometric complexity of fault systems across multiple scales. Recent studies have illuminated the significance of incorporating a fault volume or damage zone surrounding the fault in the analysis of slip dynamics. In the context of this study, we endeavor to investigate the influence of "realistic" fault geometry on the dynamics of slip events. To achieve this, we approach the problem from three interrelated perspectives:

  • Forward Source Modeling: We employ forward source modeling techniques to simulate and understand the behavior of slip events.
  • Bridging Source Modeling and Observations: We establish a connection between our source modeling and observed data by generating synthetic surface records that can be compared to actual observations.
  • Energy Budget Analysis: We meticulously analyze the variations in the energy budget that occur throughout the earthquake cycles to gain insights into the mechanics of slip events.

Our primary objectives include deciphering how deformation within the volume is accommodated by both the off-fault damage zone and the primary fault. Specifically, we aim to determine the proportion of the supplied moment rate that is absorbed by off-fault fractures during an earthquake cycle. Additionally, we seek to unravel how the diverse sequences of complex behavior observed on the fault plane manifest in the signals recorded by seismic stations. This entails assessing the distinct contributions of the main fault and off-fault fractures to the radiated signals detected at the monitoring stations. Lastly, we delve into the evolution of the medium's energy budget throughout the earthquake cycles and evaluate the dissipative contribution of off-fault fractures to ascertain their energetic role in the context of earthquake cycles.

How to cite: Bhat, H., Almakari, M., Kheirdast, N., Villafuerte, C., and Thomas, M.: A mechanical insight into the continuous chatter of a fault volume, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9007, https://doi.org/10.5194/egusphere-egu24-9007, 2024.