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1. First observations of core-transiting seismic phases on Mars.

Author

Irving, Jessica CE, Irving, Jessica CE, Lekić, Vedran, Durán, Cecilia, Drilleau, Mélanie, Kim, Doyeon, Rivoldini, Attilio, Khan, Amir, Samuel, Henri, Antonangeli, Daniele, Banerdt, William Bruce, Beghein, Caroline, Bozdağ, Ebru, Ceylan, Savas, Charalambous, Constantinos, Clinton, John, Davis, Paul, Garcia, Raphaël, Domenico Giardini, Horleston, Anna Catherine, Huang, Quancheng, Hurst, Kenneth J, Kawamura, Taichi, King, Scott D, Knapmeyer, Martin, Li, Jiaqi, Lognonné, Philippe, Maguire, Ross, Panning, Mark P, Plesa, Ana-Catalina, Schimmel, Martin, Schmerr, Nicholas C, Stähler, Simon C, Stutzmann, Eleonore, Xu, Zongbo, Irving, Jessica CE, Irving, Jessica CE, Lekić, Vedran, Durán, Cecilia, Drilleau, Mélanie, Kim, Doyeon, Rivoldini, Attilio, Khan, Amir, Samuel, Henri, Antonangeli, Daniele, Banerdt, William Bruce, Beghein, Caroline, Bozdağ, Ebru, Ceylan, Savas, Charalambous, Constantinos, Clinton, John, Davis, Paul, Garcia, Raphaël, Domenico Giardini, Horleston, Anna Catherine, Huang, Quancheng, Hurst, Kenneth J, Kawamura, Taichi, King, Scott D, Knapmeyer, Martin, Li, Jiaqi, Lognonné, Philippe, Maguire, Ross, Panning, Mark P, Plesa, Ana-Catalina, Schimmel, Martin, Schmerr, Nicholas C, Stähler, Simon C, Stutzmann, Eleonore, and Xu, Zongbo

Abstract

We present the first observations of seismic waves propagating through the core of Mars. These observations, made using seismic data collected by the InSight geophysical mission, have allowed us to construct the first seismically constrained models for the elastic properties of Mars' core. We observe core-transiting seismic phase SKS from two farside seismic events detected on Mars and measure the travel times of SKS relative to mantle traversing body waves. SKS travels through the core as a compressional wave, providing information about bulk modulus and density. We perform probabilistic inversions using the core-sensitive relative travel times together with gross geophysical data and travel times from other, more proximal, seismic events to seek the equation of state parameters that best describe the liquid iron-alloy core. Our inversions provide constraints on the velocities in Mars' core and are used to develop the first seismically based estimates of its composition. We show that models informed by our SKS data favor a somewhat smaller (median core radius = 1,780 to 1,810 km) and denser (core density = 6.2 to 6.3 g/cm3) core compared to previous estimates, with a P-wave velocity of 4.9 to 5.0 km/s at the core-mantle boundary, with the composition and structure of the mantle as a dominant source of uncertainty. We infer from our models that Mars' core contains a median of 20 to 22 wt% light alloying elements when we consider sulfur, oxygen, carbon, and hydrogen. These data can be used to inform models of planetary accretion, composition, and evolution.

Published
2023

2. Seismic detection of a deep mantle discontinuity within Mars by InSight.

Author

Huang, Quancheng, Huang, Quancheng, Schmerr, Nicholas C, King, Scott D, Kim, Doyeon, Rivoldini, Attilio, Plesa, Ana-Catalina, Samuel, Henri, Maguire, Ross R, Karakostas, Foivos, Lekić, Vedran, Charalambous, Constantinos, Collinet, Max, Myhill, Robert, Antonangeli, Daniele, Drilleau, Mélanie, Bystricky, Misha, Bollinger, Caroline, Michaut, Chloé, Gudkova, Tamara, Irving, Jessica CE, Horleston, Anna, Fernando, Benjamin, Leng, Kuangdai, Nissen-Meyer, Tarje, Bejina, Frederic, Bozdağ, Ebru, Beghein, Caroline, Waszek, Lauren, Siersch, Nicki C, Scholz, John-Robert, Davis, Paul M, Lognonné, Philippe, Pinot, Baptiste, Widmer-Schnidrig, Rudolf, Panning, Mark P, Smrekar, Suzanne E, Spohn, Tilman, Pike, William T, Giardini, Domenico, Banerdt, W Bruce, Huang, Quancheng, Huang, Quancheng, Schmerr, Nicholas C, King, Scott D, Kim, Doyeon, Rivoldini, Attilio, Plesa, Ana-Catalina, Samuel, Henri, Maguire, Ross R, Karakostas, Foivos, Lekić, Vedran, Charalambous, Constantinos, Collinet, Max, Myhill, Robert, Antonangeli, Daniele, Drilleau, Mélanie, Bystricky, Misha, Bollinger, Caroline, Michaut, Chloé, Gudkova, Tamara, Irving, Jessica CE, Horleston, Anna, Fernando, Benjamin, Leng, Kuangdai, Nissen-Meyer, Tarje, Bejina, Frederic, Bozdağ, Ebru, Beghein, Caroline, Waszek, Lauren, Siersch, Nicki C, Scholz, John-Robert, Davis, Paul M, Lognonné, Philippe, Pinot, Baptiste, Widmer-Schnidrig, Rudolf, Panning, Mark P, Smrekar, Suzanne E, Spohn, Tilman, Pike, William T, Giardini, Domenico, and Banerdt, W Bruce

Abstract

Constraining the thermal and compositional state of the mantle is crucial for deciphering the formation and evolution of Mars. Mineral physics predicts that Mars' deep mantle is demarcated by a seismic discontinuity arising from the pressure-induced phase transformation of the mineral olivine to its higher-pressure polymorphs, making the depth of this boundary sensitive to both mantle temperature and composition. Here, we report on the seismic detection of a midmantle discontinuity using the data collected by NASA's InSight Mission to Mars that matches the expected depth and sharpness of the postolivine transition. In five teleseismic events, we observed triplicated P and S waves and constrained the depth of this discontinuity to be 1,006 [Formula: see text] 40 km by modeling the triplicated waveforms. From this depth range, we infer a mantle potential temperature of 1,605 [Formula: see text] 100 K, a result consistent with a crust that is 10 to 15 times more enriched in heat-producing elements than the underlying mantle. Our waveform fits to the data indicate a broad gradient across the boundary, implying that the Martian mantle is more enriched in iron compared to Earth. Through modeling of thermochemical evolution of Mars, we observe that only two out of the five proposed composition models are compatible with the observed boundary depth. Our geodynamic simulations suggest that the Martian mantle was relatively cold 4.5 Gyr ago (1,720 to 1,860 K) and are consistent with a present-day surface heat flow of 21 to 24 mW/m2.

Published
2022

3. Constraints on the martian crust away from the InSight landing site.

Author

Li, Jiaqi, Li, Jiaqi, Beghein, Caroline, McLennan, Scott M, Horleston, Anna C, Charalambous, Constantinos, Huang, Quancheng, Zenhäusern, Géraldine, Bozdağ, Ebru, Pike, WT, Golombek, Matthew, Lekić, Vedran, Lognonné, Philippe, Bruce Banerdt, W, Li, Jiaqi, Li, Jiaqi, Beghein, Caroline, McLennan, Scott M, Horleston, Anna C, Charalambous, Constantinos, Huang, Quancheng, Zenhäusern, Géraldine, Bozdağ, Ebru, Pike, WT, Golombek, Matthew, Lekić, Vedran, Lognonné, Philippe, and Bruce Banerdt, W

Abstract

The most distant marsquake recorded so far by the InSight seismometer occurred at an epicentral distance of 146.3 ± 6.9o, close to the western end of Valles Marineris. On the seismogram of this event, we have identified seismic wave precursors, i.e., underside reflections off a subsurface discontinuity halfway between the marsquake and the instrument, which directly constrain the crustal structure away (about 4100-4500 km) from the InSight landing site. Here we show that the Martian crust at the bounce point between the lander and the marsquake is characterized by a discontinuity at about 20 km depth, similar to the second (deeper) intra-crustal interface seen beneath the InSight landing site. We propose that this 20-km interface, first discovered beneath the lander, is not a local geological structure but likely a regional or global feature, and is consistent with a transition from porous to non-porous Martian crustal materials.

Published
2022

4. Seismic detection of a deep mantle discontinuity within Mars by InSight

Author

Huang, Quancheng, Schmerr, Nicholas C., King, Scott D., Kim, Doyeon, Rivoldini, Attilio, Plesa, Ana-Catalina, Samuel, Henri, Maguire, Ross R., Karakostas, Foivos, Lekić, Vedran, Charalambous, Constantinos, Collinet, Max, Myhill, Robert, Antonangeli, Daniele, Drilleau, Melanie, Bystricky, Misha, Bollinger, Caroline, Michaut, Chloe, Gudkova, Tamara, Irving, Jessica C. E., Horleston, Anna, Fernando, Benjamin, Leng, Kuangdai, Nissen-Meyer, Tarje, Bejina, Frederic, Bozdag, Ebru, Beghein, Caroline, Waszek, Lauren, Siersch, Nicki C., Scholz, John-Robert, Davis, Paul M., Lognonné, Philippe, Pinot, Baptiste, Widmer-Schnidrig, Rudolf, Panning, Mark P., Smrekar, Suzanne E., Spohn, Tilman, Pike, William T., Giardini, Domenico, Banerdt, W. Bruce, Huang, Quancheng, Schmerr, Nicholas C., King, Scott D., Kim, Doyeon, Rivoldini, Attilio, Plesa, Ana-Catalina, Samuel, Henri, Maguire, Ross R., Karakostas, Foivos, Lekić, Vedran, Charalambous, Constantinos, Collinet, Max, Myhill, Robert, Antonangeli, Daniele, Drilleau, Melanie, Bystricky, Misha, Bollinger, Caroline, Michaut, Chloe, Gudkova, Tamara, Irving, Jessica C. E., Horleston, Anna, Fernando, Benjamin, Leng, Kuangdai, Nissen-Meyer, Tarje, Bejina, Frederic, Bozdag, Ebru, Beghein, Caroline, Waszek, Lauren, Siersch, Nicki C., Scholz, John-Robert, Davis, Paul M., Lognonné, Philippe, Pinot, Baptiste, Widmer-Schnidrig, Rudolf, Panning, Mark P., Smrekar, Suzanne E., Spohn, Tilman, Pike, William T., Giardini, Domenico, and Banerdt, W. Bruce

Abstract

Constraining the thermal and compositional state of the mantle is crucial for deciphering the formation and evolution of Mars. Mineral physics predicts that Mars’ deep mantle is demarcated by a seismic discontinuity arising from the pressure-induced phase transformation of the mineral olivine to its higher-pressure polymorphs, making the depth of this boundary sensitive to both mantle temperature and composition. Here, we report on the seismic detection of a midmantle discontinuity using the data collected by NASA’s InSight Mission to Mars that matches the expected depth and sharpness of the postolivine transition. In five teleseismic events, we observed triplicated P and S waves and constrained the depth of this discontinuity to be 1,006 ± 40 km by modeling the triplicated waveforms. From this depth range, we infer a mantle potential temperature of 1,605 ± 100 K, a result consistent with a crust that is 10 to 15 times more enriched in heat-producing elements than the underlying mantle. Our waveform fits to the data indicate a broad gradient across the boundary, implying that the Martian mantle is more enriched in iron compared to Earth. Through modeling of thermochemical evolution of Mars, we observe that only two out of the five proposed composition models are compatible with the observed boundary depth. Our geodynamic simulations suggest that the Martian mantle was relatively cold 4.5 Gyr ago (1,720 to 1,860 K) and are consistent with a present-day surface heat flow of 21 to 24 mW/m2

Published
2022
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5. Seismic detection of a deep mantle discontinuity within Mars by InSight

Author

Huang, Quancheng, Schmerr, Nicholas C., King, Scott D., Kim, Doyeon, Rivoldini, Attilio, Plesa, Ana-Catalina, Samuel, Henri, Maguire, Ross R., Karakostas, Foivos, Lekić, Vedran, Charalambous, Constantinos, Collinet, Max, Myhill, Robert, Antonangeli, Daniele, Drilleau, Melanie, Bystricky, Misha, Bollinger, Caroline, Michaut, Chloe, Gudkova, Tamara, Irving, Jessica C. E., Horleston, Anna, Fernando, Benjamin, Leng, Kuangdai, Nissen-Meyer, Tarje, Bejina, Frederic, Bozdag, Ebru, Beghein, Caroline, Waszek, Lauren, Siersch, Nicki C., Scholz, John-Robert, Davis, Paul M., Lognonné, Philippe, Pinot, Baptiste, Widmer-Schnidrig, Rudolf, Panning, Mark P., Smrekar, Suzanne E., Spohn, Tilman, Pike, William T., Giardini, Domenico, Banerdt, W. Bruce, Huang, Quancheng, Schmerr, Nicholas C., King, Scott D., Kim, Doyeon, Rivoldini, Attilio, Plesa, Ana-Catalina, Samuel, Henri, Maguire, Ross R., Karakostas, Foivos, Lekić, Vedran, Charalambous, Constantinos, Collinet, Max, Myhill, Robert, Antonangeli, Daniele, Drilleau, Melanie, Bystricky, Misha, Bollinger, Caroline, Michaut, Chloe, Gudkova, Tamara, Irving, Jessica C. E., Horleston, Anna, Fernando, Benjamin, Leng, Kuangdai, Nissen-Meyer, Tarje, Bejina, Frederic, Bozdag, Ebru, Beghein, Caroline, Waszek, Lauren, Siersch, Nicki C., Scholz, John-Robert, Davis, Paul M., Lognonné, Philippe, Pinot, Baptiste, Widmer-Schnidrig, Rudolf, Panning, Mark P., Smrekar, Suzanne E., Spohn, Tilman, Pike, William T., Giardini, Domenico, and Banerdt, W. Bruce

Abstract

Constraining the thermal and compositional state of the mantle is crucial for deciphering the formation and evolution of Mars. Mineral physics predicts that Mars’ deep mantle is demarcated by a seismic discontinuity arising from the pressure-induced phase transformation of the mineral olivine to its higher-pressure polymorphs, making the depth of this boundary sensitive to both mantle temperature and composition. Here, we report on the seismic detection of a midmantle discontinuity using the data collected by NASA’s InSight Mission to Mars that matches the expected depth and sharpness of the postolivine transition. In five teleseismic events, we observed triplicated P and S waves and constrained the depth of this discontinuity to be 1,006 ± 40 km by modeling the triplicated waveforms. From this depth range, we infer a mantle potential temperature of 1,605 ± 100 K, a result consistent with a crust that is 10 to 15 times more enriched in heat-producing elements than the underlying mantle. Our waveform fits to the data indicate a broad gradient across the boundary, implying that the Martian mantle is more enriched in iron compared to Earth. Through modeling of thermochemical evolution of Mars, we observe that only two out of the five proposed composition models are compatible with the observed boundary depth. Our geodynamic simulations suggest that the Martian mantle was relatively cold 4.5 Gyr ago (1,720 to 1,860 K) and are consistent with a present-day surface heat flow of 21 to 24 mW/m2

Published
2022

6. Thickness and structure of the martian crust from InSight seismic data

Author

Knapmeyer-Endrun, Brigitte, Panning, Mark P., Bissig, Felix, Joshi, Rakshit, Khan, Amir, Kim, Doyeon, Lekić, Vedran, Tauzin, Benoit, Tharimena, Saikiran, Plasman, Matthieu, Compaire, Nicolas, Garcia, Raphael F., Margerin, Ludovic, Schimmel, Martin, Stutzmann, Éléonore, Schmerr, Nicholas, Bozdağ, Ebru, Plesa, Ana-Catalina, Wieczorek, Mark A., Broquet, Adrien, Antonangeli, Daniele, Mclennan, Scott M., Samuel, Henri, Michaut, Chloé, Pan, Lu, Smrekar, Suzanne E., Johnson, Catherine L., Brinkman, Nienke, Mittelholz, Anna, Rivoldini, Attilio, Davis, Paul M., Lognonné, Philippe, Pinot, Baptiste, Scholz, John-Robert, Stähler, Simon, Knapmeyer, Martin, van Driel, Martin, Giardini, Domenico, Banerdt, W. Bruce, Knapmeyer-Endrun, Brigitte, Panning, Mark P., Bissig, Felix, Joshi, Rakshit, Khan, Amir, Kim, Doyeon, Lekić, Vedran, Tauzin, Benoit, Tharimena, Saikiran, Plasman, Matthieu, Compaire, Nicolas, Garcia, Raphael F., Margerin, Ludovic, Schimmel, Martin, Stutzmann, Éléonore, Schmerr, Nicholas, Bozdağ, Ebru, Plesa, Ana-Catalina, Wieczorek, Mark A., Broquet, Adrien, Antonangeli, Daniele, Mclennan, Scott M., Samuel, Henri, Michaut, Chloé, Pan, Lu, Smrekar, Suzanne E., Johnson, Catherine L., Brinkman, Nienke, Mittelholz, Anna, Rivoldini, Attilio, Davis, Paul M., Lognonné, Philippe, Pinot, Baptiste, Scholz, John-Robert, Stähler, Simon, Knapmeyer, Martin, van Driel, Martin, Giardini, Domenico, and Banerdt, W. Bruce

Published
2021

7. Thickness and structure of the martian crust from InSight seismic data

Author

Knapmeyer-Endrun, Brigitte, Panning, Mark P., Bissig, Felix, Joshi, Rakshit, Khan, Amir, Kim, Doyeon, Lekić, Vedran, Tauzin, Benoit, Tharimena, Saikiran, Plasman, Matthieu, Compaire, Nicolas, Garcia, Raphael F., Margerin, Ludovic, Schimmel, Martin, Stutzmann, Éléonore, Schmerr, Nicholas, Bozdağ, Ebru, Plesa, Ana-Catalina, Wieczorek, Mark A., Broquet, Adrien, Antonangeli, Daniele, Mclennan, Scott M., Samuel, Henri, Michaut, Chloé, Pan, Lu, Smrekar, Suzanne E., Johnson, Catherine L., Brinkman, Nienke, Mittelholz, Anna, Rivoldini, Attilio, Davis, Paul M., Lognonné, Philippe, Pinot, Baptiste, Scholz, John-Robert, Stähler, Simon, Knapmeyer, Martin, van Driel, Martin, Giardini, Domenico, Banerdt, W. Bruce, Knapmeyer-Endrun, Brigitte, Panning, Mark P., Bissig, Felix, Joshi, Rakshit, Khan, Amir, Kim, Doyeon, Lekić, Vedran, Tauzin, Benoit, Tharimena, Saikiran, Plasman, Matthieu, Compaire, Nicolas, Garcia, Raphael F., Margerin, Ludovic, Schimmel, Martin, Stutzmann, Éléonore, Schmerr, Nicholas, Bozdağ, Ebru, Plesa, Ana-Catalina, Wieczorek, Mark A., Broquet, Adrien, Antonangeli, Daniele, Mclennan, Scott M., Samuel, Henri, Michaut, Chloé, Pan, Lu, Smrekar, Suzanne E., Johnson, Catherine L., Brinkman, Nienke, Mittelholz, Anna, Rivoldini, Attilio, Davis, Paul M., Lognonné, Philippe, Pinot, Baptiste, Scholz, John-Robert, Stähler, Simon, Knapmeyer, Martin, van Driel, Martin, Giardini, Domenico, and Banerdt, W. Bruce

Published
2021

8. Planned Products of the Mars Structure Service for the InSight Mission to Mars

Author

UCL - SST/ELI/ELIC - Earth & Climate, Panning, Mark P., Lognonné, Philippe, Bruce Banerdt, W., Garcia, Raphaël, Golombek, Matthew, Kedar, Sharon, Knapmeyer-Endrun, Brigitte, Mocquet, Antoine, Teanby, Nick A., Tromp, Jeroen, Weber, Renee, Beucler, Eric, Blanchette-Guertin, Jean-Francois, Bozdağ, Ebru, Drilleau, Mélanie, Gudkova, Tamara, Hempel, Stefanie, Khan, Amir, Lekić, Vedran, Murdoch, Naomi, Plesa, Ana-Catalina, Rivoldini, Atillio, Schmerr, Nicholas, Ruan, Youyi, Verhoeven, Olivier, Gao, Chao, Christensen, Ulrich, Clinton, John, Dehant, Véronique, Giardini, Domenico, Mimoun, David, Thomas Pike, W., Smrekar, Sue, Wieczorek, Mark, Knapmeyer, Martin, Wookey, James, UCL - SST/ELI/ELIC - Earth & Climate, Panning, Mark P., Lognonné, Philippe, Bruce Banerdt, W., Garcia, Raphaël, Golombek, Matthew, Kedar, Sharon, Knapmeyer-Endrun, Brigitte, Mocquet, Antoine, Teanby, Nick A., Tromp, Jeroen, Weber, Renee, Beucler, Eric, Blanchette-Guertin, Jean-Francois, Bozdağ, Ebru, Drilleau, Mélanie, Gudkova, Tamara, Hempel, Stefanie, Khan, Amir, Lekić, Vedran, Murdoch, Naomi, Plesa, Ana-Catalina, Rivoldini, Atillio, Schmerr, Nicholas, Ruan, Youyi, Verhoeven, Olivier, Gao, Chao, Christensen, Ulrich, Clinton, John, Dehant, Véronique, Giardini, Domenico, Mimoun, David, Thomas Pike, W., Smrekar, Sue, Wieczorek, Mark, Knapmeyer, Martin, and Wookey, James

Abstract

The InSight lander will deliver geophysical instruments to Mars in 2018, including seismometers installed directly on the surface (Seismic Experiment for Interior Structure, SEIS). Routine operations will be split into two services, the Mars Structure Service(MSS) and Marsquake Service (MQS), which will be responsible, respectively, for defining the structure models and seismicity catalogs from the mission. The MSS will deliver a series of products before the landing, during the operations, and finally to the Planetary Data System(PDS) archive. Prior to the mission, we assembled a suite of a priori models of Mars,based on estimates of bulk composition and thermal profiles. Initial models during the mission will rely on modeling surface waves and impact-generated body waves independent of prior knowledge of structure. Later modeling will include simultaneous inversion of seismic observations for source and structural parameters. We use Bayesian inversion techniques to obtain robust probability distribution functions of interior structure parameters. Shallow structure will be characterized using the hammering of the heatflow probe mole, as well as measurements of surface wave ellipticity. Crustal scale structure will be constrained by measurements of receiver function and broadband Rayleigh wave ellipticity measurements. Core interacting body wave phases should be observable above modeled martian noise levels, allowing us to constrain deep structure. Normal modes of Mars should also be observable and can be used to estimate the globally averaged 1D structure, while combination with results from the InSight radio science mission and orbital observations will allow for constraint of deeper structure.

Published
2016

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