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| Titel |
Deep seismic profiling at the Argentinian and Uruguayan continental margin |
| VerfasserIn |
Michael Schnabel, Dieter Franke, Marcelo Paterlini, Alejandro Martinez |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250034554
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| Zusammenfassung |
| The opening of the southern South Atlantic resulted in the development of passive continental
margins of the volcanic type. The transition of continental to oceanic crust at this type of
margin is characterised by the presence of thickened crust showing elevated seismic
velocities. We used coincident multichannel and refraction seismic data from two profiles
offshore Argentina and Uruguay to derive the crustal structure.
The wide-angle seismic data was recorded using 8 ocean bottom hydrophones. We
identified refracted waves from the crust (Pg-phases) as well as reflected waves from the crust
mantle boundary (PmP-phases). The thickness of the sedimentary cover was estimated from
the multichannel seismic data. The application of a joint travel time inversion provided
information about the seismic velocities within the crust, as well as about the depth of the
crust mantle boundary. Tomography also allows assessing the resolution and non-uniqueness
of the final model.
Offshore Argentina at 44- S the lower crust has two distinct areas where the seismic
velocity exceeds 7.0 km/s. Each of these area has a spatial elongation of 40 to 60 km. At the
Uruguayan margin at 35- S the seismic velocities within the lower crust reaches also values
of about 7.5 km/s. A comparison of both profiles will give insight into the distribution of
magmatic products along the margin. |
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