Imperial College London
Alternate

Dr Ian Bastow

Faculty of Engineering, Department of Earth Science & Engineering

Senior Lecturer
 
 
 
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Contact

 

+44 (0)20 7594 2974i.bastow Website

 
 
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Location

 

4.45Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Wojcicka:2020:10.1029/2020JE006540,
author = {Wojcicka, N and Collins, G and Bastow, I and Teanby, N and Miljkovic, K and Rajsic, A and Daubar, I and Lognonne, P},
doi = {10.1029/2020JE006540},
journal = {Journal of Geophysical Research: Planets},
pages = {1--20},
title = {The seismic moment and seismic efficiency of small impacts on Mars},
url = {http://dx.doi.org/10.1029/2020JE006540},
volume = {125},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Since landing in late 2018, the InSight lander has been recording seismic signals on the surface of Mars.  Despite nominal pre-landing estimates of 1–3 meteorite impacts detected per Earth year, none have yet been identified seismically.  To inform revised detectability estimates, we simulated numerically a suite of small impacts onto Martian regolith and characterized their seismic source properties.  For the impactor size and velocity range most relevant for InSight, crater diameters are 1-30 m.  We found that in this range scalar seismic moment is 106−1010Nm and increases almost linearly with impact momentum.  The ratio of horizontal to vertical seismic moment tensor components is∼1, implying an almost isotropic P-wave source, for vertical impacts.  Seismic efficiencies are ∼10−6, dependent on the target crushing strength and impact velocity.  Our predictions of relatively low seismic efficiency and seismic moment suggest that meteorite impact de-tectability on Mars is lower than previously assumed.  Detection chances are best for impacts forming craters of diameter>10m.
AU  - Wojcicka,N
AU  - Collins,G
AU  - Bastow,I
AU  - Teanby,N
AU  - Miljkovic,K
AU  - Rajsic,A
AU  - Daubar,I
AU  - Lognonne,P
DO  - 10.1029/2020JE006540
EP  - 20
PY  - 2020///
SN  - 2169-9097
SP  - 1
TI  - The seismic moment and seismic efficiency of small impacts on Mars
T2  - Journal of Geophysical Research: Planets
UR  - http://dx.doi.org/10.1029/2020JE006540
UR  - https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JE006540
UR  - http://hdl.handle.net/10044/1/83734
VL  - 125
ER  -
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