Upper mantle structure beneath southern African cratons from seismic finite-frequency P- and S-body wave tomography.
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| Title: | Upper mantle structure beneath southern African cratons from seismic finite-frequency P- and S-body wave tomography. |
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| Authors: | Youssof, M.1 soliman@gfz-potsdam.de, Thybo, H.1, Artemieva, I.M.1, Levander, A.2 |
| Source: | Earth & Planetary Science Letters. Jun2015, Vol. 420, p174-186. 13p. |
| Subjects: | Cratons, Earthquake zones, Shear waves, Earth's mantle, Kaapvaal Craton (South Africa) |
| Geographic Terms: | South Africa |
| Abstract: | We present a 3D high-resolution seismic model of the southern African cratonic region from teleseismic tomographic inversion of the P- and S-body wave dataset recorded by the Southern African Seismic Experiment (SASE). Utilizing 3D sensitivity kernels, we invert traveltime residuals of teleseismic body waves to calculate velocity anomalies in the upper mantle down to a 700 km depth with respect to the ak135 reference model. Various resolution tests allow evaluation of the extent of smearing effects and help defining the optimum inversion parameters (i.e., damping and smoothness) for regularizing the inversion calculations. The fast lithospheric keels of the Kaapvaal and Zimbabwe cratons reach depths of 300–350 km and 200–250 km, respectively. The paleo-orogenic Limpopo Belt is represented by negative velocity perturbations down to a depth of ∼ 250 km , implying the presence of chemically fertile material with anomalously low wave speeds. The Bushveld Complex has low velocity down to ∼ 150 km , which is attributed to chemical modification of the cratonic mantle. In the present model, the finite-frequency sensitivity kernels allow to resolve relatively small-scale anomalies, such as the Colesberg Magnetic Lineament in the suture zone between the eastern and western blocks of the Kaapvaal Craton, and a small northern block of the Kaapvaal Craton, located between the Limpopo Belt and the Bushveld Complex. [ABSTRACT FROM AUTHOR] |
| Copyright of Earth & Planetary Science Letters is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) | |
| Database: | Engineering Source |
| FullText | Text: Availability: 0 |
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| Items | – Name: Title Label: Title Group: Ti Data: Upper mantle structure beneath southern African cratons from seismic finite-frequency P- and S-body wave tomography. – Name: Author Label: Authors Group: Au Data: <searchLink fieldCode="AR" term="%22Youssof%2C+M%2E%22">Youssof, M.</searchLink><relatesTo>1</relatesTo><i> soliman@gfz-potsdam.de</i><br /><searchLink fieldCode="AR" term="%22Thybo%2C+H%2E%22">Thybo, H.</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Artemieva%2C+I%2EM%2E%22">Artemieva, I.M.</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Levander%2C+A%2E%22">Levander, A.</searchLink><relatesTo>2</relatesTo> – Name: TitleSource Label: Source Group: Src Data: <searchLink fieldCode="JN" term="%22Earth+%26+Planetary+Science+Letters%22">Earth & Planetary Science Letters</searchLink>. Jun2015, Vol. 420, p174-186. 13p. – Name: Subject Label: Subjects Group: Su Data: <searchLink fieldCode="DE" term="%22Cratons%22">Cratons</searchLink><br /><searchLink fieldCode="DE" term="%22Earthquake+zones%22">Earthquake zones</searchLink><br /><searchLink fieldCode="DE" term="%22Shear+waves%22">Shear waves</searchLink><br /><searchLink fieldCode="DE" term="%22Earth's+mantle%22">Earth's mantle</searchLink><br /><searchLink fieldCode="DE" term="%22Kaapvaal+Craton+%28South+Africa%29%22">Kaapvaal Craton (South Africa)</searchLink> – Name: SubjectGeographic Label: Geographic Terms Group: Su Data: <searchLink fieldCode="DE" term="%22South+Africa%22">South Africa</searchLink> – Name: Abstract Label: Abstract Group: Ab Data: We present a 3D high-resolution seismic model of the southern African cratonic region from teleseismic tomographic inversion of the P- and S-body wave dataset recorded by the Southern African Seismic Experiment (SASE). Utilizing 3D sensitivity kernels, we invert traveltime residuals of teleseismic body waves to calculate velocity anomalies in the upper mantle down to a 700 km depth with respect to the ak135 reference model. Various resolution tests allow evaluation of the extent of smearing effects and help defining the optimum inversion parameters (i.e., damping and smoothness) for regularizing the inversion calculations. The fast lithospheric keels of the Kaapvaal and Zimbabwe cratons reach depths of 300–350 km and 200–250 km, respectively. The paleo-orogenic Limpopo Belt is represented by negative velocity perturbations down to a depth of ∼ 250 km , implying the presence of chemically fertile material with anomalously low wave speeds. The Bushveld Complex has low velocity down to ∼ 150 km , which is attributed to chemical modification of the cratonic mantle. In the present model, the finite-frequency sensitivity kernels allow to resolve relatively small-scale anomalies, such as the Colesberg Magnetic Lineament in the suture zone between the eastern and western blocks of the Kaapvaal Craton, and a small northern block of the Kaapvaal Craton, located between the Limpopo Belt and the Bushveld Complex. [ABSTRACT FROM AUTHOR] – Name: AbstractSuppliedCopyright Label: Group: Ab Data: <i>Copyright of Earth & Planetary Science Letters is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.) |
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| RecordInfo | BibRecord: BibEntity: Identifiers: – Type: doi Value: 10.1016/j.epsl.2015.01.034 Languages: – Code: eng Text: English PhysicalDescription: Pagination: PageCount: 13 StartPage: 174 Subjects: – SubjectFull: Cratons Type: general – SubjectFull: Earthquake zones Type: general – SubjectFull: Shear waves Type: general – SubjectFull: Earth's mantle Type: general – SubjectFull: Kaapvaal Craton (South Africa) Type: general – SubjectFull: South Africa Type: general Titles: – TitleFull: Upper mantle structure beneath southern African cratons from seismic finite-frequency P- and S-body wave tomography. Type: main BibRelationships: HasContributorRelationships: – PersonEntity: Name: NameFull: Youssof, M. – PersonEntity: Name: NameFull: Thybo, H. – PersonEntity: Name: NameFull: Artemieva, I.M. – PersonEntity: Name: NameFull: Levander, A. IsPartOfRelationships: – BibEntity: Dates: – D: 15 M: 06 Text: Jun2015 Type: published Y: 2015 Identifiers: – Type: issn-print Value: 0012821X Numbering: – Type: volume Value: 420 Titles: – TitleFull: Earth & Planetary Science Letters Type: main |
| ResultId | 1 |
