Surface-wave eikonal tomography for dense geophysical arrays
Surface-wave tomography often involves the construction of phase (or group) velocity maps through linearized inversion of measured phase (group) arrival times. Such inversions require a priori information about the medium (that is, a reference model) in order to calculate source-receiver paths, whic...
| Main Authors: | , , , |
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| Other Authors: | |
| Format: | Technical Report |
| Language: | en_US |
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Massachusetts Institute of Technology. Earth Resources Laboratory
2014
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| Subjects: | |
| Online Access: | http://hdl.handle.net/1721.1/90468 |
| _version_ | 1811094666148315136 |
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| author | Gouedard, Pierre Yao, Huajian Ernst, Fabian van der Hilst, Robert D. |
| author2 | Massachusetts Institute of Technology. Earth Resources Laboratory |
| author_facet | Massachusetts Institute of Technology. Earth Resources Laboratory Gouedard, Pierre Yao, Huajian Ernst, Fabian van der Hilst, Robert D. |
| author_sort | Gouedard, Pierre |
| collection | MIT |
| description | Surface-wave tomography often involves the construction of phase (or group) velocity maps through linearized inversion of measured phase (group) arrival times. Such inversions require a priori information about the medium (that is, a reference model) in order to calculate source-receiver paths, which is inaccurate for complex media, and requires regularization. The surface-wave eikonal tomography proposed here bypasses these limitations and has the advantage of being simple to implement and use, with virtually no input parameters. It relies on accurate phase arrival time measurement, which can be challenging for dispersive waves and complex waveforms. We present a measurement method based on the evaluation of phase arrival time diff erences at nearby receivers.We show, using an exploration data set, that the produced Rayleigh-wave velocity maps are in agreement with results from traditional tomography, but the latter have lower resolution due to the need of regularization to accommodate for the heterogeneity of the study area and noise in data. Eikonal tomography requires averaging over results from multiple sources to produce a proper image, and we evaluate this requirement to a 200 m source spacing in the considered scattering environment. In addition, we validate the approach of combining seismic interferometry and eikonal tomography, for the cases where the source coverage is inappropriate. |
| first_indexed | 2024-09-23T16:03:06Z |
| format | Technical Report |
| id | mit-1721.1/90468 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T16:03:06Z |
| publishDate | 2014 |
| publisher | Massachusetts Institute of Technology. Earth Resources Laboratory |
| record_format | dspace |
| spelling | mit-1721.1/904682019-04-12T22:07:57Z Surface-wave eikonal tomography for dense geophysical arrays Gouedard, Pierre Yao, Huajian Ernst, Fabian van der Hilst, Robert D. Massachusetts Institute of Technology. Earth Resources Laboratory tomography Surface-wave tomography often involves the construction of phase (or group) velocity maps through linearized inversion of measured phase (group) arrival times. Such inversions require a priori information about the medium (that is, a reference model) in order to calculate source-receiver paths, which is inaccurate for complex media, and requires regularization. The surface-wave eikonal tomography proposed here bypasses these limitations and has the advantage of being simple to implement and use, with virtually no input parameters. It relies on accurate phase arrival time measurement, which can be challenging for dispersive waves and complex waveforms. We present a measurement method based on the evaluation of phase arrival time diff erences at nearby receivers.We show, using an exploration data set, that the produced Rayleigh-wave velocity maps are in agreement with results from traditional tomography, but the latter have lower resolution due to the need of regularization to accommodate for the heterogeneity of the study area and noise in data. Eikonal tomography requires averaging over results from multiple sources to produce a proper image, and we evaluate this requirement to a 200 m source spacing in the considered scattering environment. In addition, we validate the approach of combining seismic interferometry and eikonal tomography, for the cases where the source coverage is inappropriate. Shell Research 2014-09-30T14:13:23Z 2014-09-30T14:13:23Z 2012 Technical Report http://hdl.handle.net/1721.1/90468 en_US Earth Resources Laboratory Industry Consortia Annual Report;2012-19 application/pdf Massachusetts Institute of Technology. Earth Resources Laboratory |
| spellingShingle | tomography Gouedard, Pierre Yao, Huajian Ernst, Fabian van der Hilst, Robert D. Surface-wave eikonal tomography for dense geophysical arrays |
| title | Surface-wave eikonal tomography for dense geophysical arrays |
| title_full | Surface-wave eikonal tomography for dense geophysical arrays |
| title_fullStr | Surface-wave eikonal tomography for dense geophysical arrays |
| title_full_unstemmed | Surface-wave eikonal tomography for dense geophysical arrays |
| title_short | Surface-wave eikonal tomography for dense geophysical arrays |
| title_sort | surface wave eikonal tomography for dense geophysical arrays |
| topic | tomography |
| url | http://hdl.handle.net/1721.1/90468 |
| work_keys_str_mv | AT gouedardpierre surfacewaveeikonaltomographyfordensegeophysicalarrays AT yaohuajian surfacewaveeikonaltomographyfordensegeophysicalarrays AT ernstfabian surfacewaveeikonaltomographyfordensegeophysicalarrays AT vanderhilstrobertd surfacewaveeikonaltomographyfordensegeophysicalarrays |