@article{fdi:010085978,
  title = {{D}etecting preseismic signals in {GRACE} gravity solutions : application to the 2011 {T}ohoku {M}-w 9.0 earthquake},
  author = {{P}anet, {I}. and {N}arteau, {C}. and {L}emoine, {J}. {M}. and {B}onvalot, {S}ylvain and {R}{\'e}my, {D}ominique},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e conduct a global analysis of {GRACE}-reconstructed gravity gradients from {J}uly 2004 to {F}ebruary 2011, to test whether the deep signals preceding the {M}arch 2011 {T}ohoku earthquake can be detected before the event as a specific feature originating from solid {E}arth. {F}irst, we improve the angular resolution of the gravity gradients using two overlapping ranges of azimuthal sensitivity to investigate short-term signals of large amplitude aligned with the orientation of the {N}orthwestern {P}acific subduction. {T}hen, we set-up a method to identify consistent solid {E}arth signals shared by different {GRACE} gravity models. {R}obust signals in a model are selected based on their spatial overlap and relative intensity with the signals of another model, so that their sensitivity to the {GRACE} data processing and ocean dealiasing product can be tested. {W}e show that the dipolar gravity gradient anomaly before the {T}ohoku earthquake is nearly unique in space and time in the {GRACE} {GRGS}03 solutions. {A} well-resolved dipolar spatial pattern, typical of dislocations within the solid {E}arth and poorly sensitive to the ocean dealiasing model, is detected. {I}n addition, the preseismic gravity gradient increase is highly consistent between the {GRGS}03 and {CSR}06 solutions, independently from their respective oceanic corrections, and can be clearly distinguished from rare anomalies of similar amplitudes all associated with the water cycle over continental areas. {O}ur approach offers solutions for the continuous monitoring of the {P}acific subduction belt to document transient slabs motions in real time from global satellite gravity fields, and their relation with shallower deformations and seismic events.},
  keywords = {{JAPON} ; {TOHOKU}},
  booktitle = {},
  journal = {{J}ournal of {G}eophysical {R}esearch : {S}olid {E}arth},
  volume = {127},
  numero = {8},
  pages = {e2022{JB}024542 [26 ]},
  ISSN = {2169-9313},
  year = {2022},
  DOI = {10.1029/2022jb024542},
  URL = {https://www.documentation.ird.fr/hor/fdi:010085978},
}