| Autor: |
Guy Lang, Yizhaq Makovsky, Boris Katsnelson, Omri Gadol, Shelly Copel, Ernst Uzhansky, Tom Kazaz |
| Rok vydání: |
2021 |
| Předmět: |
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| Zdroj: |
Proceedings of Meetings on Acoustics. |
| ISSN: |
1939-800X |
| Popis: |
In this paper we present a methodology and first results of seafloor compressional sound speed estimation in a compacting passive margin setting of the southeastern Mediterranean Sea, offshore Israel. The estimation was obtained through a coupled wide-angle reflection-refraction travel time analysis of standard commercial 2D multichannel seismic data, acquired with a 7.2km long horizontal receivers array, and geoacoustic inversion. We found that three parameters were needed to model the observed travel times: 1) the compressional sound speed at water-sediment interface c0; 2) a constant velocity gradient K within the sub-bottom sediments layer; and 3) the thickness of the relevant sub-bottom layer H2. The model considered consists of a water layer with a vertically varying sound speed profile according to the season. The thickness of this layer is constrained by the pre-known seafloor bathymetric depth of 1200 m. The base of the model is the top of a regional salt layer, which underlies the investigated sub-bottom layer and constrains H2. The estimated c0 and K are 1550 m s−1 and 0.7 s−1, respectively. The proposed method allows to estimate a relatively low (∼1500-1650 m s−1) sound speed at water-sediment interface, where it is challenging to use conventional refraction-based methods. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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