• DOI:10.1126/science.abf2966
• Corpus ID: 236179554

Upper mantle structure of Mars from InSight seismic data

@article{Khan2021UpperMS,
  title={Upper mantle structure of Mars from InSight seismic data},
  author={Amir Khan and Savas Ceylan and Martin van Driel and Domenico Giardini and Philippe Henri Lognonn{\'e} and Henri Samuel and Nicholas Charles Schmerr and Simon C. Stähler and Andrea C. Duran and Quancheng Huang and Doyeon Kim and Adrien Pierre Michel Broquet and Constantinos Charalambous and John Francis Clinton and Paul M. Davis and M{\'e}lanie Drilleau and Foivos Karakostas and Vedran Leki{\'c} and Scott M. McLennan and Ross R. Maguire and Chlo{\'e} Michaut and Mark Paul Panning and William T. Pike and Baptiste Pinot and Matthieu Plasman and John‐Robert Scholz and Rudolf Widmer-Schnidrig and Tilman Spohn and Suzanne E. Smrekar and William Bruce Banerdt},
  journal={Science},
  year={2021},
  volume={373},
  pages={434 - 438}
}

• Amir Khan, S. Ceylan, +27 authors W. Banerdt
• Published 22 July 2021
• Geology
• Science

Single seismometer structure Because of the lack of direct seismic observations, the interior structure of Mars has been a mystery. Khan et al., Knapmeyer-Endrun et al., and Stähler et al. used recently detected marsquakes from the seismometer deployed during the InSight mission to map the interior of Mars (see the Perspective by Cottaar and Koelemeijer). Mars likely has a 24- to 72-kilometer-thick crust with a very deep lithosphere close to 500 kilometers. Similar to the Earth, a low-velocity layer probably exists beneath the lithosphere. The crust of Mars is likely highly enriched in radioactive elements that help to heat this layer at the expense of the interior. The core of Mars is liquid and large, ∼1830 kilometers, which means that the mantle has only one rocky layer rather than two like the Earth has. These results provide a preliminary structure of Mars that helps to constrain the different theories explaining the chemistry and internal dynamics of the planet. Science, abf2966, abf8966, abi7730, this issue p. 434, p. 438, p. 443 see also abj8914, p. 388 Data from the InSight mission on Mars help constrain the structure and properties of the martian interior. For 2 years, the InSight lander has been recording seismic data on Mars that are vital to constrain the structure and thermochemical state of the planet. We used observations of direct (P and S) and surface-reflected (PP, PPP, SS, and SSS) body-wave phases from eight low-frequency marsquakes to constrain the interior structure to a depth of 800 kilometers. We found a structure compatible with a low-velocity zone associated with a thermal lithosphere much thicker than on Earth that is possibly related to a weak S-wave shadow zone at teleseismic distances. By combining the seismic constraints with geodynamic models, we predict that, relative to the primitive mantle, the crust is more enriched in heat-producing elements by a factor of 13 to 20. This enrichment is greater than suggested by gamma-ray surface mapping and has a moderate-to-elevated surface heat flow.