EGU25-15813, updated on 09 Apr 2025
https://doi.org/10.5194/egusphere-egu25-15813
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
The focal mechanism of Marsquake s1197a near Hesperia Planum
Jinlai Hao1,2, Quanhong Li1,2, Zhuowei Xiao1,2, and Juan Li1,2,3
Jinlai Hao et al.
  • 1Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of sciences, Beiing, china
  • 2College of Earth and Planetary Sciences, University of Chinese Academy of sciences, Beijing, China
  • 3Heilongiang Mohe Observatory of Geophysics, institute of Geology and Geophysics, Chinese Academy of sciences, Beiing, china

Our study, employing deep-learning-based polarization estimation to locate low-frequency family marsquakes, has detected seven marsquakes in the vicinity of Hesperia Planum. Among these, Marsquake s1197a is the largest event, with a magnitude of 3.6. The high signal-to-noise ratio (SNR) of the data has facilitated an in-depth investigation into its focal mechanism. We have determined the relative arrival time between the sS and S phases in the tangential component, which is approximately 15 seconds. This measurement, in conjunction with the previous Martian crustal model, has led to an estimated depth of 30 km for the marsquake. This depth was held constant throughout our subsequent focal mechanism analysis. To characterize the source of the marsquake, we utilized a double-couple focal mechanism model and calculated synthetic waveforms using the FK method. The focal mechanism was constrained by three components of the S wave and the vertical P wave. Our preferred focal mechanism is a thrust mechanism. Notably, non-extensional focal mechanisms are also included among our top 200 focal mechanisms. The consistency between our preferred focal mechanism and the older compressional structures near Hesperia Planum suggests that the region may have experienced marsquakes at present. This finding implies that the seismic activity on Mars is more active than previously thought.

How to cite: Hao, J., Li, Q., Xiao, Z., and Li, J.: The focal mechanism of Marsquake s1197a near Hesperia Planum, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15813, https://doi.org/10.5194/egusphere-egu25-15813, 2025.