Joint Inversion of 1-D Magnetotelluric and Surface-Wave Dispersion Data with an Improved Multi-Objective Genetic Algorithm and Application to the Data of the Longmenshan Fault Zone

SUMMARY Multiphysics imaging for data inversion is of growing importance in many branches of science and engineering. Cross-gradient constraint has been considered as a feasible way to reduce the non-uniqueness problem inherent in inversion process by finding geometrically consistent images from multigeophysical data. Based on OCCAM inversion algorithm, a direct inversion method of 2-D profile velocity structure with surface wave dispersion data is proposed. Then we jointly invert the profiles of magnetotelluric and surface wave dispersion data with cross-gradient constraints. Three synthetic models, including block homogeneous or heterogeneous models with consistent or inconsistent discontinuities in velocity and resistivity, are presented to gauge the performance of the joint inversion scheme. We find that owning to the complementary advantages of the two geophysical data sets, the models recovered with structure coupling constraints exhibit higher resolution in the classification of complex geologic units and settle some imaging problems caused by the separate inversion methods. Finally, a realistic velocity model from the NE Tibetan Plateau and its corresponding resistivity model calculated by empirical law are used to test the effectiveness of the joint inversion scheme in the real geological environment.

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3D v P and v S models of southeastern margin of the Tibetan plateau from joint inversion of body-wave arrival times and surface-wave dispersion data

Earthquake Science ◽

10.1007/s11589-017-0175-6 ◽

2017 ◽

Vol 30 (1) ◽

pp. 17-32 ◽

Cited By ~ 2

Author(s):

Lina Gao ◽

Haijiang Zhang ◽

Huajian Yao ◽

Hui Huang

Keyword(s):

Surface Wave ◽

Joint Inversion ◽

Body Wave ◽

Wave Dispersion ◽

The Tibetan Plateau ◽

Surface Wave Dispersion ◽

Arrival Times ◽

Dispersion Data ◽

Southeastern Margin ◽

Wave Arrival

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USTClitho2.0: Updated Unified Seismic Tomography Models for Continental China Lithosphere from Joint Inversion of Body-Wave Arrival Times and Surface-Wave Dispersion Data

Seismological Research Letters ◽

10.1785/0220210122 ◽

2021 ◽

Author(s):

Shoucheng Han ◽

Haijiang Zhang ◽

Hailiang Xin ◽

Weisen Shen ◽

Huajian Yao

Keyword(s):

Surface Wave ◽

Joint Inversion ◽

Body Wave ◽

Wave Dispersion ◽

Surface Wave Dispersion ◽

Arrival Times ◽

Velocity Models ◽

Dispersion Data ◽

Wave Travel ◽

Wave Arrival

Abstract Xin et al. (2019) presented 3D seismic velocity models (VP and VS) of crust and uppermost mantle of continental China using seismic body-wave travel-time tomography, which are referred to as Unified Seismic Tomography Models for Continental China Lithosphere 1.0 (USTClitho1.0). Compared with previous models of continental China, the VP and VS models of USTClitho1.0 have the highest spatial resolution of 0.5°–1.0° in the horizontal direction and are useful for better understanding the complex tectonics of continental China. Although USTClitho1.0 is implicitly constrained by surface-wave data by using the VS model from surface-wave tomography and the converted VP model as initial models for body-wave travel-time tomography, the predicted surface-wave dispersion curves from USTClitho1.0 do not fit the observed data well. Here, we present updated 3D VP and VS models of the continental China lithosphere (USTClitho2.0) by joint inversion of body-wave arrival times and surface-wave dispersion data. Compared with the previous joint inversion scheme of Zhang et al. (2014), similar to Fang et al. (2016), it is further improved by including the sensitivity of surface-wave dispersion data to VP in the new joint inversion system. As a result, the shallow VP structure is also better imaged. In addition, the new joint inversion scheme considers the large topography variations between the eastern and western parts of China. Thus, USTClitho2.0 better resolves the upper-crustal structure of the Tibetan plateau. Compared with USTClitho1.0, USTClitho2.0 fits both body-wave arrival times and surface-wave dispersion data. Thus, the new velocity models are more accurate and can serve as a better reference model for regional-scale tomography and geodynamic studies in continental China.

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Imaging the subsurface using induced seismicity and ambient noise: 3-D tomographic Monte Carlo joint inversion of earthquake body wave traveltimes and surface wave dispersion

Geophysical Journal International ◽

10.1093/gji/ggaa230 ◽

2020 ◽

Vol 222 (3) ◽

pp. 1639-1655

Author(s):

Xin Zhang ◽

Corinna Roy ◽

Andrew Curtis ◽

Andy Nowacki ◽

Brian Baptie

Keyword(s):

Surface Wave ◽

Ambient Noise ◽

Velocity Structure ◽

Joint Inversion ◽

Body Wave ◽

Source Parameters ◽

Wave Dispersion ◽

Inversion Method ◽

Surface Wave Dispersion ◽

Wave Data

SUMMARY Seismic body wave traveltime tomography and surface wave dispersion tomography have been used widely to characterize earthquakes and to study the subsurface structure of the Earth. Since these types of problem are often significantly non-linear and have non-unique solutions, Markov chain Monte Carlo methods have been used to find probabilistic solutions. Body and surface wave data are usually inverted separately to produce independent velocity models. However, body wave tomography is generally sensitive to structure around the subvolume in which earthquakes occur and produces limited resolution in the shallower Earth, whereas surface wave tomography is often sensitive to shallower structure. To better estimate subsurface properties, we therefore jointly invert for the seismic velocity structure and earthquake locations using body and surface wave data simultaneously. We apply the new joint inversion method to a mining site in the United Kingdom at which induced seismicity occurred and was recorded on a small local network of stations, and where ambient noise recordings are available from the same stations. The ambient noise is processed to obtain inter-receiver surface wave dispersion measurements which are inverted jointly with body wave arrival times from local earthquakes. The results show that by using both types of data, the earthquake source parameters and the velocity structure can be better constrained than in independent inversions. To further understand and interpret the results, we conduct synthetic tests to compare the results from body wave inversion and joint inversion. The results show that trade-offs between source parameters and velocities appear to bias results if only body wave data are used, but this issue is largely resolved by using the joint inversion method. Thus the use of ambient seismic noise and our fully non-linear inversion provides a valuable, improved method to image the subsurface velocity and seismicity.

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Reliable workflow for inversion of seismic receiver function and surface wave dispersion data: a “13 BB Star” case study

Journal of Seismology ◽

10.1007/s10950-019-09888-1 ◽

2019 ◽

Vol 24 (1) ◽

pp. 101-120

Author(s):

Kajetan Chrapkiewicz ◽

Monika Wilde-Piórko ◽

Marcin Polkowski ◽

Marek Grad

Keyword(s):

Surface Wave ◽

Inverse Problems ◽

Receiver Function ◽

Joint Inversion ◽

Wave Dispersion ◽

Receiver Functions ◽

P Wave ◽

Surface Wave Dispersion ◽

Phase Velocity Dispersion ◽

Wide Range

AbstractNon-linear inverse problems arising in seismology are usually addressed either by linearization or by Monte Carlo methods. Neither approach is flawless. The former needs an accurate starting model; the latter is computationally intensive. Both require careful tuning of inversion parameters. An additional challenge is posed by joint inversion of data of different sensitivities and noise levels such as receiver functions and surface wave dispersion curves. We propose a generic workflow that combines advantages of both methods by endowing the linearized approach with an ensemble of homogeneous starting models. It successfully addresses several fundamental issues inherent in a wide range of inverse problems, such as trapping by local minima, exploitation of a priori knowledge, choice of a model depth, proper weighting of data sets characterized by different uncertainties, and credibility of final models. Some of them are tackled with the aid of novel 1D checkerboard tests—an intuitive and feasible addition to the resolution matrix. We applied our workflow to study the south-western margin of the East European Craton. Rayleigh wave phase velocity dispersion and P-wave receiver function data were gathered in the passive seismic experiment “13 BB Star” (2013–2016) in the area of the crust recognized by previous borehole and refraction surveys. Final models of S-wave velocity down to 300 km depth beneath the array are characterized by proximity in the parameter space and very good data fit. The maximum value in the mantle is higher by 0.1–0.2 km/s than reported for other cratons.

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Surface wave dispersion and upper mantle structure beneath southern Germany from joint inversion of network recorded teleseismic events

Geophysical Research Letters ◽

10.1029/93gl02685 ◽

1993 ◽

Vol 20 (21) ◽

pp. 2375-2378 ◽

Cited By ~ 22

Author(s):

Stefan Stange ◽

Wolfgang Friederich

Keyword(s):

Surface Wave ◽

Upper Mantle ◽

Joint Inversion ◽

Wave Dispersion ◽

Mantle Structure ◽

Surface Wave Dispersion ◽

Southern Germany ◽

Upper Mantle Structure ◽

Teleseismic Events

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Short-period surface-wave dispersion and shallow crustal structure of central and eastern Tennessee

Bulletin of the Seismological Society of America ◽

10.1785/bssa0820020962 ◽

1992 ◽

Vol 82 (2) ◽

pp. 962-979

Author(s):

Paul C. Yao ◽

James Dorman

Keyword(s):

Surface Wave ◽

Half Space ◽

Crustal Structure ◽

Group Velocity Dispersion ◽

Wave Dispersion ◽

Surface Wave Dispersion ◽

Zero Crossing ◽

Clastic Rocks ◽

Dispersion Data ◽

Short Period

Abstract Group velocity dispersion of explosion-generated seismic surface waves with periods ranging from 0.2 to 1.5 sec is used to investigate shallow crustal structure of eastern and central Tennessee. Several modes of both Rayleigh and Love waves can be identified and separated on the seismograms of seven SARSN regional network stations by zero-phase digital filtering. Dispersion data for sinusoidal wave motion were based on digitized zero-crossing times. By forward modeling, we find that a wave guide of at least two layers over a half-space can adequately represent our particular multi-mode, narrow-band observations. In a layered section about 3 km thick, lower velocities characterize outcropping clastic rocks of the Cumberland plateau, and higher velocities correspond to shallow carbonate rocks of the Nashville Dome. Half-space shear velocities of about 3.9 km/sec appear to represent lower Paleozoic carbonate lithology deeper than 2 to 4 km on most of the observed paths. Our best data, interpreted jointly with earlier data of Oliver and Ewing (1958) and of Chen et al. (1989), have a composite period range of 0.2 to 40 sec, but they represent different Appalachian paths. Group velocities over this broad spectrum are satisfied by a complex model with two low-velocity layers. The uniqueness of this model cannot be demonstrated, but it represents important hypotheses concerning regional geologic features that can be tested more rigorously by improved surface-wave dispersion data.

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