Seafloor analysis based on multibeam bathymetry and backscatter data = Meeresbodenanalyse auf der Basis von Bathymetrie und akustischer Rückstreuung

Large areas of the worlds oceans are still unexplored. Previously unknown structures and ecosystems are discovered due to the increasing exploration of the oceans, in particular at the continental margin and the continental shelf. Research is essential to understand these structures and to analyze t...

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Bibliographic Details
Main Author: Beyer, A.
Format: Other/Unknown Material
Language:unknown
Published: Alfred Wegener Institute for Polar and Marine Research 2006
Subjects:
Online Access:https://epic.awi.de/id/eprint/26176/
https://epic.awi.de/id/eprint/26176/1/Bey2006b.pdf
https://hdl.handle.net/10013/epic.26070
https://hdl.handle.net/10013/epic.26070.d001
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Summary:Large areas of the worlds oceans are still unexplored. Previously unknown structures and ecosystems are discovered due to the increasing exploration of the oceans, in particular at the continental margin and the continental shelf. Research is essential to understand these structures and to analyze their potential and importance for human society and the ecosystem. This PhD thesis is one part of multidisciplinary research at the European continental margin. Hydroacustic methods were applied in order to identify and distinguish different seabed structures and facies.Hydroacustic techniques are an established approach to analyze the seafloor. Echo intensity was used in this study for interpretation in addition to the travel time of the acoustic signal. The ship-borne multibeam system Hydrosweep DS-2 and the sub-bottom profiler Parasound were used for data recording.The investigation areas of this study comprise the Håkon Mosby mud volcano situated at the Norwegian-Barents-Svalbard continental margin and the carbonate mounds in the Belgica mound province together with adjacent channels situated in the Porcupine Seabight at the Irish continental margin. Mud volcanoes and carbonate mounds are characterized by active sediment and transport processes and are related to the existence of subsurface hydrocarbon, mainly methane. Seafloor channels indicate sediment transport in lateral and vertical direction. These structures are focus of recent research due to the contribution of methane to the carbon cycle.A terrain model of the Håkon Mosby mud volcano was created providing the basis for detailed studies which require precise positioning for sampling and observation devices. The fine structure of the mud volcano was mapped by dense survey lines and overlapping swathes. The Håkon Mosby mud volcano is located at a water depth of about 1270 m and can be separated into three morphological segments: weak, crater-like center (950 m diameter, 12 m height), circular embankment (1350 m diameter, 100 m breadth, 2 m height) and the ...