Forward and adjoint simulations of seismic wave propagation on fully unstructured hexahedral meshes

Peter, Daniel; Komatitsch, Dimitri; Luo, Yuanqiu; Martin, Roland; Goff, Nicolas Le; Casarotti, Emanuele; Loher, Pieyre Le; Magnoni, Federica; Liu, Qinya; Blitz, Céline; Nissen‐Meyer, Tarje; Basini, Piero; Tromp, Jeroen

doi:10.1111/j.1365-246x.2011.05044.x

Cited by 298 publications

(188 citation statements)

References 129 publications

(193 reference statements)

Supporting

Mentioning

187

Contrasting

Order By: Relevance

“…Moreover, the method uses high-order Lagrange polynomials to interpolate the wavefield, together with Gauss-Lobatto-Legendre (GLL) quadrature, both defined on the same GLL points, thus leading to a perfectly diagonal mass matrix. Therefore, it is possible to adopt an explicit time scheme to integrate the global system, thereby accommodating a very efficient implementation on parallel computers (e.g., Tromp et al, 2008;Komatitsch, 2011;Peter et al, 2011). In addition, the highdegree Lagrange polynomials assure exponential spatial accuracy.…”

Section: Methodsmentioning

confidence: 99%

“…In the following sections we present source and wavespeed models implemented in the SEM code SPECFEM3D_ Cartesian (Peter et al, 2011) for simulations of the 2009 M w 6.3 L'Aquila earthquake. Comparisons between observed data and SEM synthetics produced for flat versus undulating models emphasize the importance of topography for realistic ground-motion simulations.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Spectral-Element Simulations of Seismic Waves Generated by the 2009 L'Aquila Earthquake

Magnoni¹,

Casarotti²,

Michelini³

et al. 2013

Bulletin of the Seismological Society of America

View full text Add to dashboard Cite

We adopt a spectral-element method (SEM) to perform numerical simulations of the complex wavefield generated by the 6 April 2009 M w 6.3 L'Aquila earthquake in central Italy. The mainshock is represented by a finite-fault solution obtained by inverting strong-motion and Global Positioning System data, testing both 1D and 3D wavespeed models for central Italy. Surface topography, attenuation, and the Moho discontinuity are also accommodated. Including these complexities is essential to accurately simulate seismic-wave propagation. Three-component synthetic waveforms are compared to corresponding velocimeter and strong-motion recordings. The results show a favorable match between data and synthetics up to ∼0:5 Hz in a 200 km × 200 km × 60 km model volume, capturing features mainly related to topography or low-wavespeed basins. We construct synthetic peak ground velocity maps that, for the 3D model, are in good agreement with observations, thus providing valuable information for seismic-hazard assessment. Exploiting the SEM in combination with an adjoint method, we calculate finite-frequency kernels for specific seismic arrivals. These kernels capture the volumetric sensitivity associated with the selected waveform and highlight prominent effects of topography on seismic-wave propagation in central Italy.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Spectral-Element Simulations of Seismic Waves Generated by the 2009 L'Aquila Earthquake

Magnoni¹,

Casarotti²,

Michelini³

et al. 2013

Bulletin of the Seismological Society of America

View full text Add to dashboard Cite

show abstract

“…Very accurate and perfectly scalable on parallel computers, this method has a long success history in modelling seismic wave propagation (e.g. Padovani et al 1994;Fichtner et al 2009;Peter et al 2011;Cupillard et al 2012). The 3-D earth model used contains all main global discontinuities included in PREM (Dziewonski & Anderson 1981) and the recent 3-D S-velocity mantle model from Ritsema et al (2011).…”

Section: Synthetic Seismogramsmentioning

confidence: 99%

Arrival angle anomalies of Rayleigh waves observed at a broadband array: a systematic study based on earthquake data, full waveform simulations and noise correlations

et al. 2015

View full text Add to dashboard Cite

S U M M A R YDeviation of seismic surface waves from the great-circle between source and receiver is illustrated by the anomalies in the arrival angle, that is the difference between the observed backazimuth of the incident waves and the great-circle. Such arrival angle anomalies have been known for decades, but observations remain scattered. We present a systematic study of arrival angle anomalies of fundamental mode Rayleigh waves (20-100 s period interval) from 289 earthquakes and recorded by a broadband network LAPNET, located in northern Finland. These observations are compared with those of full waveform synthetic seismograms for the same events, calculated in a 3-D Earth and also compared with those of seismograms obtained by ambient noise correlation. The arrival angle anomalies for individual events are complex, and have significant variations with period. On average, the mean absolute deviation decreases from ∼9 • at 20 s period to ∼3 • at 100 s period. The synthetic seismograms show the same evolution, albeit with somewhat smaller deviations. While the arrival angle anomalies are fairly well simulated at long periods, the deviations at short periods are very poorly modelled, demonstrating the importance of the continuous improvement of global crustal models. At 20-30 s period, both event data and numerical simulations have strong multipathing, and relative amplitude changes between different waves will induced differences in deviations between very closely located events. The source mechanism has only limited influence on the deviations, demonstrating that they are directly linked to propagation effects, including near-field effects in the source area. This observation is confirmed by the comparison with seismic noise correlation records, that is where the surface waves correspond to those emitted by a point source at the surface, as the two types of observations are remarkably similar in the cases where earthquakes are located close to seismic stations. This agreement additionally confirms that the noise correlations capture the complex surface wave propagation.

show abstract

“…The latest tool for assimilating this information into seismic velocity models is fully three-dimensional (3-D) waveform tomography [e.g., Tarantola, 1988;Tromp et al, 2005;Chen et al, 2007aChen et al, , 2007bBen Hadj Ali et al, 2009a, 2009bChen, 2011;Fichtner, 2011;Lekic and Romanowicz, 2011;Liu and Gu, 2012;Colli et al, 2013;Fichtner et al, 2013;French et al, 2013;Prieux et al, 2013;Schiemenz and Igel, 2013]. Full-3-D tomography (F3DT) accounts for the physics of wave excitation and propagation by numerically solving the inhomogeneous equations of motion for a heterogeneous, anelastic solid [Olsen et al, 1995;Komatitsch and Tromp, 1999;Cui et al, 2010;Peter et al, 2011]. The starting model is 3-D, and the Fréchet (sensitivity) kernels are calculated using the full physics of 3-D wave propagation [Zhao et al, 2005[Zhao et al, , 2006Tromp et al, 2005;Liu and Tromp, 2006].…”

Section: Introductionmentioning

confidence: 99%

Full‐3‐D tomography for crustal structure in Southern California based on the scattering‐integral and the adjoint‐wavefield methods

et al. 2014

View full text Add to dashboard Cite

We have successfully applied full-3-D tomography (F3DT) based on a combination of the scattering-integral method (SI-F3DT) and the adjoint-wavefield method (AW-F3DT) to iteratively improve a 3-D starting model, the Southern California Earthquake Center (SCEC) Community Velocity Model version 4.0 (CVM-S4). In F3DT, the sensitivity (Fréchet) kernels are computed using numerical solutions of the 3-D elastodynamic equation and the nonlinearity of the structural inversion problem is accounted for through an iterative tomographic navigation process. More than half-a-million misfit measurements made on about 38,000 earthquake seismograms and 12,000 ambient-noise correlagrams have been assimilated into our inversion. After 26 F3DT iterations, synthetic seismograms computed using our latest model, CVM-S4.26, show substantially better fit to observed seismograms at frequencies below 0.2 Hz than those computed using our 3-D starting model CVM-S4 and the other SCEC CVM, CVM-H11.9, which was improved through 16 iterations of AW-F3DT. CVM-S4.26 has revealed strong crustal heterogeneities throughout Southern California, some of which are completely missing in CVM-S4 and CVM-H11.9 but exist in models obtained from previous crustal-scale 2-D active-source refraction tomography models. At shallow depths, our model shows strong correlation with sedimentary basins and reveals velocity contrasts across major mapped strike-slip and dip-slip faults. At middle to lower crustal depths, structural features in our model may provide new insights into regional tectonics. When combined with physics-based seismic hazard analysis tools, we expect our model to provide more accurate estimates of seismic hazards in Southern California.

show abstract

Forward and adjoint simulations of seismic wave propagation on fully unstructured hexahedral meshes

Cited by 298 publications

References 129 publications

Spectral-Element Simulations of Seismic Waves Generated by the 2009 L'Aquila Earthquake

Spectral-Element Simulations of Seismic Waves Generated by the 2009 L'Aquila Earthquake

Arrival angle anomalies of Rayleigh waves observed at a broadband array: a systematic study based on earthquake data, full waveform simulations and noise correlations

Full‐3‐D tomography for crustal structure in Southern California based on the scattering‐integral and the adjoint‐wavefield methods

Contact Info

Product

Resources

About