Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection
With the publication of Holbrook et al. (2003) the field of seismic oceanography experienced a major momentum. Several authors since then (Nandi et al., 2004; Holbrook and Fer, 2005; Paramo and Holbrook, 2005) could show that those reflections within the water column correspond to thin layers with s...
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ftawi:oai:epic.awi.de:15829 2024-09-09T20:00:21+00:00 Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection Uenzelmann-Neben, Gabriele Klaeschen, D. Krahmann, G. Reston, T. Visbeck, M. 2006 https://epic.awi.de/id/eprint/15829/ https://hdl.handle.net/10013/epic.25895 unknown Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , Klaeschen, D. , Krahmann, G. , Reston, T. and Visbeck, M. (2006) Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection , American Geophysical Union, Fall Meeting, San Francisco, Dec . hdl:10013/epic.25895 EPIC3American Geophysical Union, Fall Meeting, San Francisco, Dec, pp. 10-15 Conference notRev 2006 ftawi 2024-06-24T03:59:21Z With the publication of Holbrook et al. (2003) the field of seismic oceanography experienced a major momentum. Several authors since then (Nandi et al., 2004; Holbrook and Fer, 2005; Paramo and Holbrook, 2005) could show that those reflections within the water column correspond to thin layers with strong vertical temperature gradients. Those reflections hence represent a chance to trace those temperature gradients over large distances.Weak seismic reflections within the water column south of South Africa gave rise to the question whether here traces of the Agulhas Current or Agulhas Retroflection can be observed. A careful reprocessing of the data led to the imaging of fields of reflections pointing towards a 135 km broad and about 1000 m deep reaching well stratified area with strong reflection amplitudes and several weaker reflections extending down to at least 1500 m water depth over the whole area of investigation.To image both the boundaries between the water masses as reflections and the different properties of the long wavelength velocity variations in depth special imaging technigues like prestack depth migration analysis were performed. Further, the temperature gradients from the short wavelength properties as velocity and density contrasts were determind by a two step inversion of acoustic amplitude versus angle analysis to better quantify the variations of the water masses of the Agulhas Current.References:Holbrook, W.S., and I. Fer, Ocean internal wave spectra inferred from seismic reflection transects, 2005, Geophys. Res. Lett., 32, L15604, doi:10.1029/2005GL023733.Nandi, P., W.S. Holbrook, S. Pearse, P. Paramo, and R.W. Schmitt, 2004, Seismic reflection imaging of Norwegian Sea water mass boundaries, Geophys. Res. Lett., 31, L23311, doi:10.1029/2004GL021325.Páramo, P., and W. S. Holbrook, 2005, Temperature contrasts in the water column inferred from amplitude-versus-offset analysis of acoustic reflections, Geophys. Res. Lett., v. 32, L24611, doi:10.1029/2005GL024533. Conference Object Norwegian Sea Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Norwegian Sea |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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ftawi |
language |
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description |
With the publication of Holbrook et al. (2003) the field of seismic oceanography experienced a major momentum. Several authors since then (Nandi et al., 2004; Holbrook and Fer, 2005; Paramo and Holbrook, 2005) could show that those reflections within the water column correspond to thin layers with strong vertical temperature gradients. Those reflections hence represent a chance to trace those temperature gradients over large distances.Weak seismic reflections within the water column south of South Africa gave rise to the question whether here traces of the Agulhas Current or Agulhas Retroflection can be observed. A careful reprocessing of the data led to the imaging of fields of reflections pointing towards a 135 km broad and about 1000 m deep reaching well stratified area with strong reflection amplitudes and several weaker reflections extending down to at least 1500 m water depth over the whole area of investigation.To image both the boundaries between the water masses as reflections and the different properties of the long wavelength velocity variations in depth special imaging technigues like prestack depth migration analysis were performed. Further, the temperature gradients from the short wavelength properties as velocity and density contrasts were determind by a two step inversion of acoustic amplitude versus angle analysis to better quantify the variations of the water masses of the Agulhas Current.References:Holbrook, W.S., and I. Fer, Ocean internal wave spectra inferred from seismic reflection transects, 2005, Geophys. Res. Lett., 32, L15604, doi:10.1029/2005GL023733.Nandi, P., W.S. Holbrook, S. Pearse, P. Paramo, and R.W. Schmitt, 2004, Seismic reflection imaging of Norwegian Sea water mass boundaries, Geophys. Res. Lett., 31, L23311, doi:10.1029/2004GL021325.Páramo, P., and W. S. Holbrook, 2005, Temperature contrasts in the water column inferred from amplitude-versus-offset analysis of acoustic reflections, Geophys. Res. Lett., v. 32, L24611, doi:10.1029/2005GL024533. |
format |
Conference Object |
author |
Uenzelmann-Neben, Gabriele Klaeschen, D. Krahmann, G. Reston, T. Visbeck, M. |
spellingShingle |
Uenzelmann-Neben, Gabriele Klaeschen, D. Krahmann, G. Reston, T. Visbeck, M. Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection |
author_facet |
Uenzelmann-Neben, Gabriele Klaeschen, D. Krahmann, G. Reston, T. Visbeck, M. |
author_sort |
Uenzelmann-Neben, Gabriele |
title |
Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection |
title_short |
Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection |
title_full |
Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection |
title_fullStr |
Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection |
title_full_unstemmed |
Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection |
title_sort |
seismic reflections within the water column south of south africa: indications for the agulhas retroflection |
publishDate |
2006 |
url |
https://epic.awi.de/id/eprint/15829/ https://hdl.handle.net/10013/epic.25895 |
geographic |
Norwegian Sea |
geographic_facet |
Norwegian Sea |
genre |
Norwegian Sea |
genre_facet |
Norwegian Sea |
op_source |
EPIC3American Geophysical Union, Fall Meeting, San Francisco, Dec, pp. 10-15 |
op_relation |
Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , Klaeschen, D. , Krahmann, G. , Reston, T. and Visbeck, M. (2006) Seismic Reflections Within the Water Column South of South Africa: Indications for the Agulhas Retroflection , American Geophysical Union, Fall Meeting, San Francisco, Dec . hdl:10013/epic.25895 |
_version_ |
1809931569124605952 |