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An integrated geophysical study of Vestbakken Volcanic Province, western Barents Sea continental margin, and adjacent oceanic crust
Title: | An integrated geophysical study of Vestbakken Volcanic Province, western Barents Sea continental margin, and adjacent oceanic crust |
Authors: | Libak, Audun Browse this author | Mjelde, Rolf Browse this author | Keers, Henk Browse this author | Faleide, Jan Inge Browse this author | Murai, Yoshio Browse this author →KAKEN DB |
Keywords: | Seismic modeling | Ocean bottom seismometer | Mafic feeder dykes | Oceanic and continental crust | Vestbakken Volcanic Province |
Issue Date: | Jun-2012 |
Publisher: | Springer Netherlands |
Journal Title: | Marine Geophysical Research |
Volume: | 33 |
Issue: | 2 |
Start Page: | 185 |
End Page: | 207 |
Publisher DOI: | 10.1007/s11001-012-9155-3 |
Abstract: | This paper describes results from a geophysical study in the Vestbakken Volcanic Province, located on the central parts of the western Barents Sea continental margin, and adjacent oceanic crust in the Norwegian-Greenland Sea. The results are derived mainly from interpretation and modeling of multichannel seismic, ocean bottom seismometer and land station data along a regional seismic profile. The resulting model shows oceanic crust in the western parts of the profile. This crust is buried by a thick Cenozoic sedimentary package. Low velocities in the bottom of this package indicate overpressure. The igneous oceanic crust shows an average thickness of 7.2 km with the thinnest crust (5-6 km) in the southwest and the thickest crust (8-9 km) close to the continent-ocean boundary (COB). The thick oceanic crust is probably related to high mantle temperatures formed by brittle weakening and shear heating prior to continental breakup. The COB is interpreted in the central parts of the profile where the velocity structure and Bouguer anomalies change significantly. East of the COB Moho depths increase while the vertical velocity gradient decreases. Below the assumed center for Early Eocene volcanic activity the model shows increased velocities in the crust. These increased crustal velocities are interpreted to represent Early Eocene mafic feeder dykes. East of the zone of volcanoes velocities in the crust decrease and sedimentary velocities are observed at depths of more than 10 km. The amount of crustal intrusions is much lower in this area than farther west. East of the Knølegga Fault crystalline basement velocities are brought close to the seabed. This fault marks the eastern limit of thick Cenozoic and Mesozoic packages on central parts of the western Barents Sea continental margin. |
Rights: | The final publication is available at www.springerlink.com |
Type: | article (author version) |
URI: | http://hdl.handle.net/2115/49692 |
Appears in Collections: | 理学院・理学研究院 (Graduate School of Science / Faculty of Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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Submitter: 村井 芳夫
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