Detection and modeling of Rayleigh wave induced patterns in the ionosphere

[1] Global Positioning System (GPS) allows the detection of ionospheric disturbances associated with the vertical displacements of most of the major shallow seismic events. We describe a method to model the time and space distributions of Rayleigh wave induced total electron content (TEC) patterns detected by a dense GPS array. We highlight the conditions for which a part of the ionospheric pattern can be directly measured, at teleseismic distance and above the epicenter. In particular, a satellite elevation angle lower than 40° is a favorable condition to detect Rayleigh wave induced ionospheric waves. The coupling between the solid Earth and its atmosphere is modeled by computing the normal modes of the solid Earth–atmosphere system. We show the dependency of the coupling efficiency on various atmospheric conditions. By summation of the normal modes we model the atmospheric perturbation triggered by a given earthquake. This shows that a part of the observation is a Rayleigh-induced radiation pattern and therefore characteristic of the seismic rupture. Through atmosphere-ionosphere coupling, we model the ionospheric perturbation. After the description of the local geomagnetic field anisotropic effects, we show how the observation geometry is strongly affecting the radiation pattern. This study deals with the related data for two earthquakes with far-field and near-field observations using the Japanese GPS network GEONET: after the 12 May 2008 Wenchuan earthquake (China) and after the 25 September 2003 Tokachi-Oki earthquake (Japan), respectively. Waveforms and patterns are compared with the observed TEC perturbations, providing a new step toward the use of ionospheric data in seismological applications.

[1]  Eric Jeansou,et al.  Ground-based GPS imaging of ionospheric post-seismic signal , 2006 .

[2]  Takashi Maruyama,et al.  Detection of ruptures of Andaman fault segments in the 2004 great Sumatra earthquake with coseismic ionospheric disturbances , 2006 .

[3]  Philippe Lognonné,et al.  Ionospheric remote sensing of the Denali Earthquake Rayleigh surface waves , 2003 .

[4]  Raphaël F. Garcia,et al.  Response of the ionosphere to the seismic trigerred acoustic waves: Electron density and electromagnetic fluctuations , 2009 .

[5]  H. Kanamori,et al.  Atmospheric pressure change associated with the 2003 Tokachi‐Oki earthquake , 2006, Geophysical Research Letters.

[6]  P. Lognonné,et al.  Normal modes modelling of post‐seismic ionospheric oscillations , 2001 .

[7]  P. Lognonné.  Normal modes and seismograms in an anelastic rotating Earth , 1991 .

[8]  G. Schubert,et al.  Atmospheric Airglow Fluctuations due to a Tsunami‐driven Gravity Wave Disturbance , 2010 .

[9]  Vladislav V. Kiryushkin,et al.  Two‐mode long‐distance propagation of coseismic ionosphere disturbances , 2009 .

[10]  P. Lognonné,et al.  85.16 Higher order perturbation theory: 3D synthetic seismogram package , 2003 .

[11]  Michael P. Hickey,et al.  Propagation of tsunami‐driven gravity waves into the thermosphere and ionosphere , 2009 .

[12]  H. Kanamori,et al.  Acoustic resonant oscillations between the atmosphere and the solid earth during the 1991 Mt. Pinatubo eruption , 2010 .

[13]  J. Bernard Minster,et al.  GPS detection of ionospheric perturbations following the January 17, 1994, Northridge Earthquake , 1995 .

[14]  Philippe Lognonné,et al.  Ionospheric gravity waves detected offshore Hawaii after tsunamis , 2010 .

[15]  Anthony J. Mannucci,et al.  A global mapping technique for GPS‐derived ionospheric total electron content measurements , 1998 .

[16]  Philippe Lognonné,et al.  Acoustic waves generated from seismic surface waves: propagation properties determined from Doppler sounding observations and normal-mode modelling , 2004 .

[17]  Glenn Joyce,et al.  Sami2 is Another Model of the Ionosphere (SAMI2): A new low-latitude ionosphere model , 2000 .

[18]  Philippe Lognonné,et al.  Nostradamus: The radar that wanted to be a seismometer , 2010 .

[19]  W. Hooke.  The ionospheric response to internal gravity waves: 1. The F2 region response , 1970 .

[20]  D. Bilitza,et al.  International Reference Ionosphere 2007: Improvements and new parameters , 2008 .

[21]  J. Bernard Minster,et al.  Ionospheric signature of surface mine blasts from Global Positioning System measurements , 2002 .

[22]  Hélène Hébert,et al.  Three‐dimensional waveform modeling of ionospheric signature induced by the 2004 Sumatra tsunami , 2006 .

[23]  Shuanggen Jin,et al.  TEC response to the 2008 Wenchuan Earthquake in comparison with other strong earthquakes , 2010 .

[24]  Yousuke Miyagi,et al.  Surface deformation caused by shallow magmatic activity at Okmok volcano, Alaska, detected by GPS campaigns 2000–2002 , 2004 .

[25]  Nils Olsen,et al.  The 10th generation international geomagnetic reference field , 2005 .

[26]  Takeshi Sagiya,et al.  A decade of GEONET: 1994–2003 —The continuous GPS observation in Japan and its impact on earthquake studies— , 2004 .

[27]  Hiroo Kanamori,et al.  COMPUTATION OF SEISMOGRAMS AND ATMOSPHERIC OSCILLATIONS BY NORMAL-MODE SUMMATION FOR A SPHERICAL EARTH MODEL WITH REALISTIC ATMOSPHERE , 1998 .

[28]  D. Drob,et al.  Nrlmsise-00 Empirical Model of the Atmosphere: Statistical Comparisons and Scientific Issues , 2002 .

[29]  T. M. Georges,et al.  Wave‐induced fluctuations in ionospheric electron content: A model indicating some observational biases , 1970 .

[30]  Philippe Lognonné,et al.  Geomagnetic dependence of ionospheric disturbances induced by tsunamigenic internal gravity waves , 2007 .

[31]  Yuji Yagi,et al.  Source rupture process of the 2003 Tokachi-oki earthquake determined by joint inversion of teleseismic body wave and strong ground motion data , 2004 .

[32]  D. L. Anderson,et al.  Preliminary reference earth model , 1981 .

[33]  N. Kobayashi,et al.  A new method to calculate normal modes , 2007 .

[34]  É. Calais,et al.  Lithosphere-atmosphere-ionosphere coupling after the 2003 explosive eruption of the Soufriere Hills Volcano, Montserrat , 2009 .

[35]  H. Kanamori,et al.  Ionospheric detection of gravity waves induced by tsunamis , 2005 .

[36]  E. Astafyeva,et al.  Dependence of waveform of near-field coseismic ionospheric disturbances on focal mechanisms , 2009 .

[37]  E. L. Afraimovich,et al.  The shock-acoustic waves generated by earthquakes , 2001 .

[38]  S. Aoi,et al.  Three‐dimensional finite difference simulation of long‐period ground motions for the 2003 Tokachi‐oki, Japan, earthquake , 2008 .

[39]  M. A. Macleod.  Sporadic E Theory. I. Collision-Geomagnetic Equilibrium , 1966 .

[40]  J. Ping,et al.  Directivity and apparent velocity of the coseismic ionospheric disturbances observed with a dense GPS array , 2005 .

[41]  François Crespon.  Tomographie 2D et 3D de l'ionosphère par GPS : applications aux aléas géophysiques , 2007 .