The Marsquake Service Reference Catalogue

The Marsquake Service (MQS) [1] is finalizing the release of the reference catalogue of Martian seismicity recorded by NASA’s InSight mission. Previous catalogue versions [2] listed over 1300 events classified by their observed frequency content into i) low frequency (LF) and broadband (BB) - the key events for constraining interior structure, ii) 2.4 Hz and high frequency (HF) -  representing the majority of events with weak signals and enigmatic origin,  and iii) very high frequency (VF) events, including several nearby impacts [3].

Since the last release in April 2023, directly following the mission end, MQS has reviewed the entire data set, also using denoised data sets [4,5] to refine phase picks, back azimuths, and ensuring consistency across the catalogue. 

For distance computation, MQS has adopted an updated suite of interior models, now applied to all event types [6, 7]. Previously 2.4 Hz, HF, and VF events were located using constant crustal velocities. However,  new insights from observations of impacts and surface waves [8,9,10] suggest these events propagate through deeper interior layers, leading to significantly larger distances.

MQS has revised the frequency-based event classification, incorporating spectral analysis [11] and other parameters such as distance and seasonality to improve event characterization. Events are grouped into three interpretation types:

• i) Tectonic events, mostly located ~30° east of InSight in Cerberus Fossae and in few other regions with deeper sources, include most LF and BB events with low corner frequencies.
• ii) Swarm events are a subset of HF and 2.4 Hz events clustered in ~44° distance with shallow seasonal sources, though their source region remains speculative; this group has been significantly expanded through deep learning techniques [5].
• iii) Meteorite impacts, characterized by high corner frequencies, encompass VF events, several large BB events, and HF/2.4Hz events located outside of the swarm region.

The reference catalogue includes over 1900 events with improved locations and new interpretation types, providing a more comprehensive view of Martian seismicity observed by InSight.

[1] Clinton et al (2018), 10.1007/s11214-018-0567-5

[2] Ceylan et al. (2022), 10.1016/j.pepi.2022.106943

[3] Garcia et al (2022), 10.1038/s41561-022-01014-0

[4] Scholz et al (2020), 10.1029/2020EA001317

[5] Dahmen et al. (2024), 10.1093/gji/ggae279

[6] Khan et al. (2023), 10.1038/s41586-023-06586-4

[7] Samuel et al. (2023), 10.1038/s41586-023-06601-8

[8] Posiolova et al. (2022), 10.1126/science.abq7704

[9] Panning et al. (2023), 10.1029/2022GL101270

[10] Charalambous et al. (in press)

[11] Stähler et al. (in prep.)