Asbjørn Breivik

• Tan, Pingchuan; Sippel, Judith; Breivik, Asbjørn Johan; Meessen, Chrisitian & Scheck-Wenderoth, Magdalena (2018). Lithospheric Control on Asthenospheric Flow From the Iceland Plume: 3-D Density Modeling of the Jan Mayen-East Greenland Region, NE Atlantic. Journal of Geophysical Research (JGR): Solid Earth.  ISSN 2169-9313.  123(10), s 9223- 9248 . doi: 10.1029/2018JB015634 Vis sammendrag

  The density structure of the oceanic lithosphere north of Iceland is key for understanding the effects of the Iceland plume on the greater Jan Mayen-East Greenland Region. We obtain the 3-D density structure of the sediments and the crust from regional reflection and refraction seismic lines. The temperature and related density structures of the mantle between 50 and 250 km are derived from a shear wave velocity (Vs) tomography model. To assess the density between the Moho and 50-km depth, we combine forward and inverse 3-D gravity modeling. Beneath the Middle Kolbeinsey Ridge (MKR) region, a deep, broad negative mantle density anomaly occurs under the Kolbeinsey Ridge. It is overlain by a narrower uppermost mantle NE-SW elongated negative density anomaly, which is increasingly displaced eastward of the spreading axis northward. It crosses the West Jan Mayen Fracture Zone and becomes weaker approaching the Mohn’s spreading ridge. The effect of this anomaly is consistent with significantly shallower basement on the eastern side of the MKR. We interpret this as the result of thermal erosion of the lithosphere by hot asthenospheric flow out from the Iceland plume, possibly the main driver for several eastward jumps of the MKR during the last 5.5 Ma. The cause for the deviation of the flow may be that the West Jan Mayen Fracture Zone is easier to cross in a region where the difference in lithospheric thickness is small. That implies that the bottom lithospheric topography exerts a regional but not local influence on upper asthenospheric flow.

• Aarseth, Iselin; Mjelde, Rolf; Breivik, Asbjørn Johan; Minakov, Alexander; Faleide, Jan Inge; Flueh, Ernst R. & Huismans, Ritske (2017). Crustal structure and evolution of the Arctic Caledonides: Results fromcontrolled-source seismology. Tectonophysics.  ISSN 0040-1951.  718, s 9- 24 . doi: 10.1016/j.tecto.2017.04.022 Fulltekst i vitenarkiv.
• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf; Flueh, Ernst R. & Murai, Yoshio (2017). A new tectono-magmatic model for the Lofoten/Vesterålen Margin at the outer limit of the Iceland Plume influence. Tectonophysics.  ISSN 0040-1951.  718, s 25- 44 . doi: 10.1016/j.tecto.2017.07.002 Fulltekst i vitenarkiv.
• Tan, Pingchuan; Breivik, Asbjørn Johan; Trønnes, Reidar G; Mjelde, Rolf; Azuma, Ryosuke & Eide, Sigurd (2017). Crustal structure and origin of the Eggvin Bank west of Jan Mayen, NE Atlantic. Journal of Geophysical Research (JGR): Solid Earth.  ISSN 2169-9313.  122(1), s 43- 62 . doi: 10.1002/2016JB013495 Fulltekst i vitenarkiv.
• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf; Flueh, Ernst R. & Murai, Yoshio (2014). Magmatic development of the outer Vøring margin from seismic data. Journal of Geophysical Research (JGR): Solid Earth.  ISSN 2169-9313.  119(9), s 6733- 6755 . doi: 10.1002/2014JB011040
• Howell, Samuel Matthew; Ito, Garrett; Breivik, Asbjørn Johan; Rai, Abhishek Kumar; Mjelde, Rolf; Hanan, Barry; Sayit, Kaan & Vogt, Peter (2014). The origin of the asymmetry in the Iceland hotspot along the Mid-Atlantic Ridge from continental breakup to present-day. Earth and Planetary Science Letters.  ISSN 0012-821X.  392, s 143- 153 . doi: 10.1016/j.epsl.2014.02.020
• Breivik, Asbjørn Johan; Mjelde, Rolf; Faleide, Jan Inge & Murai, Yoshio (2012). The eastern Jan Mayen microcontinent volcanic margin. Geophysical Journal International.  ISSN 0956-540X.  188(3), s 798- 818 . doi: 10.1111/j.1365-246X.2011.05307.x Vis sammendrag

  The Jan Mayen microcontinent (JMMC) in the NE Atlantic was created through two Cenozoic rift episodes. Originally part of East Greenland, the JMMC rifted from NW Europe during the Early Eocene under extensive magmatism. The eastern margin is conjugate to the Møre–Faeroes volcanic margin. The western JMMC margin underwent prolonged extension before it finally separated from East Greenland during the Late Oligocene. Here we present the modelling by forward/inverse ray tracing of two wide-angle seismic profiles acquired using Ocean Bottom Seismometers, across the northern and the southern JMMC. Early Eocene breakup magmatism at the eastern JMMC produced an igneous thickness of 7–9 km in the north, and 12–14 km in the south. While the continent is clear in the north, the southern JMMC appears to be affected by later Icelandic magmatism. Reduced seismic velocity and increased crustal thickness are compatible with continental crust adjacent to the volcanic margin in the south, but the continental presence towards the Iceland shelf is less clear. Our magnetic track off the southern JMMC gives seafloor spreading rates comparable to that of the conjugate Møre Margin. Transition to ultraslow seafloor spreading occurs at ∼43 Ma, indicating onset of major deformation of the JMMC. Calculating the igneous thickness—mean VP relationship at the eastern volcanic margin gives the typical positive correlation seen elsewhere on the NE Atlantic margins. The results indicate temperature driven breakup magmatism under passive mantle upwelling, with a maximum mantle temperature anomaly of ∼50 ◦C in the north and 90–150 ◦C in the south.

• Breivik, Asbjørn Johan; Mjelde, Rolf; Raum, Thomas Johan; Faleide, Jan Inge; Murai, Yoshio & Flueh, Ernst R. (2010). Crustal structure beneath the Trondelag Platform and adjacent areas of the mid-Norwegian margin, as derived from wide-angle seismic and potential field data. Norsk Geologisk Tidsskrift.  ISSN 0029-196X.  90(4), s 141- 161
• Breivik, Asbjørn; Faleide, Jan Inge; Mjelde, Rolf & Flueh, Ernst R. (2009). Magma productivity and early seafloor spreading rate correlation on the northern Vøring Margin, Norway — Constraints on mantle melting. Tectonophysics.  ISSN 0040-1951.  468(1-4), s 206- 223 . doi: 10.1016/j.tecto.2008.09.020
• Bruvoll, Vibeke; Breivik, Asbjørn Johan; Mjelde, Rolf & Pedersen, Rolf-Birger (2009). Burial of the Mohn-Knipovich seafloor spreading ridge by the Bear Island Fan: Time constraints on tectonic evolution from seismic stratigraphy. Tectonics.  ISSN 0278-7407.  28 . doi: 10.1029/2008TC002396
• Mjelde, Rolf; Faleide, Jan Inge; Breivik, Asbjørn Johan & Raum, Thomas Johan (2009). Lower crustal composition and crustal lineaments on the Vøring Margin, NE Atlantic: A review. Tectonophysics.  ISSN 0040-1951.  472(1-4), s 183- 193 . doi: 10.1016/j.tecto.2008.04.018
• Breivik, Asbjørn; Faleide, Jan Inge & Mjelde, Rolf (2008). Neogene magmatism northeast of the Aegir and Kolbeinsey ridges, NE Atlantic: Spreading ridge-mantle plume interaction?. Geochemistry Geophysics Geosystems.  ISSN 1525-2027.  9 . doi: 10.1029/2007GC001750
• Faleide, Jan Inge; Tsikalas, Filippos; Breivik, Asbjørn Johan; Mjelde, R; Ritzmann, Oliver; Engen, Øyvind; Wilson, Jonas & Eldholm, O (2008). Structure and evolution of the continental margin off Norway and Barents Sea. Episodes.  ISSN 0705-3797.  31
• Mjelde, Rolf; Breivik, Asbjørn Johan; Raum, Thomas; Mittelstaedt, E; Ito, G & Faleide, Jan Inge (2008). Magmatic and tectonic evolution of the North Atlantic. Journal of the Geological Society.  ISSN 0016-7649.  165, s 31- 42
• Mjelde, Rolf; Breivik, Asbjørn; Raum, Thomas Johan; Mittelstaedt, Eric; Ito, Garrett & Faleide, Jan Inge (2008). Magmatic and tectonic evolution of the North Atlantic. Journal of the Geological Society.  ISSN 0016-7649.  165(1), s 31- 42 . doi: 10.1144/0016-76492007-018
• Mjelde, Rolf; Raum, Thomas Johan; Breivik, Asbjørn & Faleide, Jan Inge (2008). Crustal transect across the North Atlantic. Marine Geophysical Researches.  ISSN 0025-3235.  29(2), s 73- 87 . doi: 10.1007/s11001-008-9046-9
• Breivik, Asbjørn Johan; Mjelde, Rolf; Faleide, Jan Inge & Murai, Yoshio (2006). Rates of continental breakup magmatism and seafloor spreading in the Norway Basin-Iceland plume interaction. Journal of Geophysical Research (JGR).  ISSN 0148-0227.  111 . doi: 10.1029/2005JB004004

Se alle arbeider i Cristin

• Breivik, Asbjørn Johan (2018). Along-Margin Variability in Breakup Magmatism, NE Atlantic.
• Breivik, Asbjørn Johan; Tan, Pingchuan & Mjelde, Rolf (2018). Development of the Igneous Logi Ridge, NE Atlantic, From Seismic Reflection Data.
• Gibbons, Steven John; Maupin, Valerie; Kolstad, Christian; Kværna, Tormod & Breivik, Asbjørn Johan (2018). Improved location estimates for seismicity along the northern North Atlantic Ridge.
• Tan, Pingchuan; Breivik, Asbjørn Johan & Mjelde, Rolf (2018). Development of the igneous Logi Ridge and surrounding sedimentation, NE Atlantic, from seismic reflection data..
• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf; Flueh, Ernst R. & Murai, Yoshio (2017). Origin of the Vøring Plateau, offshore Norway – interplay between timing of rifting and emplacement of plume material.
• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf; Flueh, Ernst R. & Murai, Yoshio (2017). The Transition from Volcanic to Rift Dominated Crustal Breakup – From the Vøring Plateau to the Lofoten Margin, Norway.
• Tan, Pingchuan; Sippel, Judith; Breivik, Asbjørn Johan; Scheck-Wenderoth, Magdalena & Meessen, Christian (2017). 3D Density Structure of Oceanic Lithosphere Affected by A Plume: A Case Study from the Greater Jan Mayen-East Greenland Region (NE Atlantic).
• Aarseth, Iselin; Mjelde, Rolf; Breivik, Asbjørn Johan; Huismans, Ritske & Faleide, Jan Inge (2016). Barents Sea Paleozoic basement and basin configurations: Crustal structure from deep seismic and potential field data.
• Aarseth, Iselin; Mjelde, Rolf; Breivik, Asbjørn Johan; Huismans, Ritske & Faleide, Jan Inge (2016). Barents Sea Paleozoic basement and basin configurations: Crustal structure from deep seismic and potential field data.
• Aarseth, Iselin; Mjelde, Rolf; Breivik, Asbjørn Johan; Minakov, Alexander; Huismans, Ritske & Faleide, Jan Inge (2016). Barents Sea Crustal and Upper Mantle Structure from Deep Seismic and Potential Field Data.
• Mjelde, Rolf; Breivik, Asbjørn Johan; Minakov, Alexander; Huismans, Ritske & Faleide, Jan Inge (2016). Barents Sea Crustal and Upper Mantle Structure from Deep Seismic and Potential Field Data.
• Tan, Pingchuan; Sippel, Judith; Breivik, Asbjørn Johan; Scheck-Wenderoth, Magdalena & Meeßen, Christian (2016). Crustal and mantle structure of the greater Jan MayenEast Greenland region (NE Atlantic) from combined 3D structural, Swave velocity, and gravity modeling.
• Faleide, Jan Inge; Mahajan, Aatisha; Gabrielsen, Roy Helge; Breivik, Asbjørn Johan; Planke, Sverre & Myklebust, Reidun (2015). Basement and Late Paleozoic basin configurations in the western and central Barents Sea.
• Tan, Pingchuan; Breivik, Asbjørn Johan; Mjelde, Rolf & Azuma, Ryosuke (2015). Constraining formation of the Eggvin Bank (West of Jan Mayen, N. Atlantic) from OBS data.
• Abdelmalak, Mohamed Mansour; Faleide, Jan Inge; Planke, Sverre; Theissen-Krah, Sonja; Zastrozhnov, Dmitrii; Breivik, Asbjørn Johan; Gernigon, Laurent & Myklebust, Reidun (2014). Breakup magmatism style on the North Atlantic Igneous Province: insight from Mid-Norwegian volcanic margin.
• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf; Murai, Yoshio & Flueh, Ernst R. (2014). Breakup Style and Magmatic Underplating West of the Lofoten Islands, Norway, Based on OBS Data.
• Faleide, Jan Inge; Breivik, Asbjørn Johan; Blaich, Olav A.; Tsikalas, Filippos; Planke, Sverre; Abdelmalak, Mohamed Mansour; Mjelde, Rolf & Myklebust, Reidun (2014). Structure and degree of magmatism of North and South Atlantic rifted margins.
• Abdelmalak, Mohamed Mansour; Faleide, Jan Inge; Planke, Sverre; Breivik, Asbjørn Johan; Gernigon, Laurent & Myklebust, Reidun (2013). Magmatism and break-up on the NE Atlantic: the nature and influence of the lower crustal body on margin structure.
• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf; Flueh, Ernst R. & Murai, Yoshio (2013). Magmatic development of the outer Vøring Margin.
• Faleide, Jan Inge; Planke, Sverre; Abdelmalak, Mohamed Mansour; Theissen-Krah, Sonja; Zastrozhnov, Dmitry; Tsikalas, Filipos; Breivik, Asbjørn Johan; Torsvik, Trond Helge; Gaina, Carmen; Schmid, Daniel Walter; Myklebust, Reidun & Mjelde, Rolf (2013). Structure and evolution of the NE Atlantic conjugate margins off Norway and Greenland.
• Planke, Sverre; Sassier, Caroline; Polteau, Stephane; Faleide, Jan Inge; Galland, Olivier; Breivik, Asbjørn Johan & Myklebust, Reidun (2013). Salt distribution and sub-salt basins on the conjugate Barents Sea - Northeast Greenland continental shelves.
• Rai, Abhishek Kumar; Breivik, Asbjørn Johan & Mjelde, Rolf (2013). Lower Crustal Reflectivity bands and Magma Emplacement in Norwegian Sea, NE Atlantic.
• Rai, Abhishek Kumar; Breivik, Asbjørn Johan; Mjelde, Rolf & Pedersen, Rolf-Birger (2013). Nature of the seismic crust at the Aegir Ridge: A downward continuation approach.
• Breivik, Asbjørn Johan (2012). Mantle melting in the NE Atlantic Igneous Province. Vis sammendrag

  The northeast Atlantic margins form part of a large mafic igneous province, which has been attributed to the arrival of the Iceland mantle plume. Sill complexes and magmatic underplating formed at the outer margins at breakup, followed by the formation of oceanic crust 2-4 times normal thickness. High magma productivity typically lasted 3-6 Ma after breakup. After that, excess magmatism continued along the Faeroe-Iceland-Greenland Ridge. Other models, ranging from small-scale convection to increased mantle fertility, have also been proposed to explain the excess magmatism. By comparing the oceanic crustal thickness of the volcanic margins with average P-wave velocities, the melting process of the mantle can be estimated. The results indicate elevated mantle temperatures confined to a finite reservoir underneath the margins at breakup time, consistent with a plume model. But additional processes appear to augment the melt production at some margin segments. Later magmatic rejuvenation may also mask original processes in some areas.

• Breivik, Asbjørn Johan; Mjelde, Rolf; Rai, Abhishek Kumar & Frassetto, Andy (2012). Geophysical survey of the Eggvin Bank and Logi Ridge - Greenland Sea. Vis sammendrag

  The northern Greenland Sea has a number of features associated with excess volcanism. These include the Jan Mayen island, the Jan Mayen Plateau north of, and the Eggvin Bank west of Jan Mayen, and the Vesteris Seamount far to the north. In the summer of 2011, we collected an Ocean Bottom Seismometer (OBS) profile across the Eggvin Bank, returning four good data sets. We also collected single-channel reflection seismic (SCS) data along the OBS line. The profile crosses the transform part of the West Jan Mayen Fracture Zone (WJMFZ), which connects seafloor spreading between the Kolbeinsey and Mohn ridges. Between the WJMFZ and the Vesteris Seamount there is a narrow ridge 170-180 km long, ending in a few seamounts in the east. It disturbs the magnetic seafloor anomalies, and has no conjugate on the Norwegian margin. It thus appears to be younger than the Eocene seafloor it lies on. Trend and position points to Traill Ø in East Greenland, which had magmatism at ~36 Ma. We name it the Logi Ridge after Norse mythology, where Logi is the master of fire, brother of Aegir, master of the sea. We have collected five SCS profiles across this ridge in order to study the surrounding sedimentation pattern. We also collected gravity and magnetic data along all profiles. Initial results show two flat-topped seamounts on the Eggvin Bank, and a flat-topped Logi Ridge, indicating that these have been at sealevel. The sedimentary strata show recent vertical movement north of the WJMFZ near the Jan Mayen Plateau, and compression around the Logi Ridge.

• Howell, Samuel M.; Breivik, Asbjørn Johan & Mjelde, Rolf (2012). Mantle Convection beneath the Aegir Ridge, a Shadow in the Iceland Hotspot.
• Rai, Abhishek Kumar; Breivik, Asbjørn Johan; Mjelde, Rolf; Hanan, Barry; Ito, Garrett; Howell, Samuel M.; Pedersen, Rolf B. & Vogt, Peter (2012). Analysis of converted S-waves and gravity anomaly along Aegir Ridge: implications for crustal lithology.
• Savit, K; Hanan, Barry; Ito, Garrett; Howel, SM; Vogt, Peter; Breivik, Asbjørn Johan; Mjelde, Rolf & Pedersen, Rolf B. (2012). The trace and Pb isotope chemistry of the Jan Mayen Fracture Zone and the extinct Aegir Ridge.
• Sayit, Kaan; Breivik, Asbjørn Johan; Mjelde, Rolf & Pedersen, Rolf-Birger (2012). The trace and Pb isotope chemistry of the Jan Mayen Fracture Zone and the extict Aegir Ridge.
• Sayit, Kaan; Breivik, Asbjørn Johan; Mjelde, Rolf & Pedersen, Rolf-Birger (2012). The trace and Pb isotope chemistry of the Jan Mayen Fracture Zone and the extinct Aegir Ridge.
• Breivik, Asbjørn Johan; Mjelde, Rolf; Faleide, Jan Inge & Murai, Yoshio (2011). The Eastern Jan Mayen Micro-Continent Volcanic Margin.
• Howell, S.; Vogt, Peter R.; Breivik, Asbjørn Johan; Mjelde, Rolf & Pedersen, Rolf B. (2011). Geochemistry and Pb Isotopes from the Jan Mayen Fracture Zone and the Extinct Aegir Ridge.
• Rai, Abhishek Kumar; Breivik, Asbjørn Johan & Mjelde, Rolf (2011). Seismic Structure of the Extinct Aegir Ridge in Norwegian Basin, N.E. Atlantic.
• Breivik, Asbjørn Johan (2010). Volcanic margins – hotspot origin or not? A closer look at the NE Atlantic.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2010). The Norwegian volcanic margin revisited.
• Breivik, Asbjørn Johan; Mjelde, Rolf; Raum, Thomas; Faleide, Jan Inge; Murai, Yoshio & Flueh, ER (2010). Crustal structure of the inner mid-Norwegian continental margin – Trøndelag Platform, from wide-angle seismic and potential field data.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2009). Conjugate volcanic margin breakup of the mid-Norwegian and East Greenland Margins –using crustal scale velocity and thickness data to determine breakup style.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2009). Northeast Atlantic Igneous Province volcanic margin development.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2009). Oceanic Intraplate Magmatism Off The Vøring Volcanic Passive Margin, Norway – Constraints On Origin From Seismic Velocity Structure.
• Clark, SA; Ritzmann, Oliver; Faleide, Jan Inge; Mjelde, Rolf; Glørstad, Evy; Leever, K; Gabrielsen, Roy H. & Breivik, Asbjørn Johan (2009). Rift basin architecture and crustal thinning in the southwestern Barents Sea.
• Faleide, Jan Inge; Tsikalas, Filippos; Breivik, Asbjørn Johan & Mjelde, Rolf (2009). Structure and evolution of the continental margin off Norway and the Barents Sea and its conjugate off Greenland.
• Faleide, Jan Inge; Tsikalas, Filippos; Breivik, Asbjørn Johan; Mjelde, Rolf; Blaich, Olav Antonio & eldholm, olav (2009). Structure and Evolution of the NE Atlantic Region and Links to the Arctic.
• Mjelde, Rolf; Breivik, Asbjørn Johan & Faleide, Jan Inge (2009). Northeast Atlantic Igneous Province volcanic margin development.
• Tsikalas, Filippos; Faleide, Jan Inge; Blaich, Olav Antonio; Breivik, Asbjørn Johan; Mjelde, Rolf & Eldholm, O (2009). Late Mesozoic-Cenozoic Evolution of the Conjugate Lofoten-Vesterålen (Nordland VI-VII) and NE Greenland Continental Margins: Implications for the Potentially Developed Petroleum System.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2008). Determining volcanic continental margin breakup style on the Norwegian Margin - Which criteria are important and can they be generalized?.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2008). East Greenland – mid-Norway asymmetric conjugate volcanic margin development.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2008). Enigmatic Neogene magmatism NE of Iceland - Major magmatic underplating off the Norwegian margin.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2008). Enigmatic Neogene magmatism NE of Iceland - major magmatic underplating off the Norwegian margin.
• Clark, Stephen Anthony; Ritzmann, Oliver; Faleide, Jan Inge; Mjelde, Rolf; Leever, Karen Agneta; Glørstad-Clark, Evy; Gabrielsen, Roy Helge & Breivik, Asbjørn Johan (2008). Linking deep structures and basin formation in the Barents Sea. 33rd International Geological Congress, Abstracts.  CD-ROM
• Faleide, Jan Inge; Tsikalas, Filippos; Breivik, Asbjørn Johan; Mjelde, Rolf; Ritzmann, Oliver; Engen, Øyvind; Wilson, Jonas & Eldholm, Olav (2008). Basin evolution at the Norwegian-Greenland conjugate margins in the NE Atlantic.
• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2007). The dynamics of continental breakup-related magmatism on the Norwegian volcanic margin.
• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf & Tsikalas, Filippos (2007). Continental breakup and magmatic development of the mid-Norwegian margin, Euromargins 2003 OBS Experiment.
• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf & Tsikalas, Filippos (2007). Timing of Continental breakup at the mid-Norwegian margin, Euromargins 2003 OBS Experiment.
• Faleide, Jan Inge; Engen, Øyvind; Tsikalas, Filippos; Breivik, Asbjørn Johan & Ritzmann, Oliver (2007). Crustal structure of the mainly sheared western Barents Sea-Svalbard margin.
• Faleide, Jan Inge; Engen, Øyvind; Tsikalas, Filippos; Breivik, Asbjørn Johan & Ritzmann, Oliver (2007). Opening of the northern North Atlantic and formation of the sheared western Barents Sea-Svalbard and NE Greenland margins.
• Faleide, Jan Inge; Tsikalas, Filippos; Breivik, Asbjørn Johan; Mjelde, Rolf; Wilson, Jonas & Eldholm, Olav (2007). NE Atlantic breakup and evolution of the Norwegian-Greenland conjugate volcanic margins.
• Tsikalas, Filippos; Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf & Eldholm, Olav (2007). Crustal structure, continental breakup and magmatism at the Lofoten-Vesterålen margin, off Norway, constrained by the Euromargins 2003 OBS Experiment.
• Tsikalas, Filippos; Faleide, Jan Inge; Breivik, Asbjørn Johan; Mjelde, Rolf; Wilson, Jonas; Eldholm, Olav & Kusznir, Nick (2007). Structure and evolution of the northern Vøring and Lofoten-Vesterålen margins, and their conjugate NE Greenland margin.
• Brandsdottir, Bryndis; Hooft, Emilie; Mjelde, Rolf; Shimamura, Hideki; Murai, Yoshio; Barclay, Andrew; Breivik, Asbjørn Johan & Takanami, Tetsuo (2006). Evolution of a divergent plate boundary; from the active Kolbeinsey Ridge, N-Iceland to the exinct Ægir Ridge, Norwegian Sea. Vis sammendrag

  The continental margin off mid-Norway is a volcanic passive margin created during the earliest Eocene, and large volumes of magmatic rocks were emplaced during and a few M.y. after continental breakup. In 2003, an ocean bottom seismometer/hydrophone survey was acquired on the Vøring and Lofoten-Vesterålen Margins. The main targets are continental breakup processes, early seafloor spreading, and along-margin variation of magma productivity. The P-wave data were modeled by a combined forward ray-tracing and inversion into 2D velocity-depth models. The continent-ocean transition zone is usually well defined as a rapid increase of P-wave velocities at mid- to lower-crustal levels. This transition may occur over a distance of only 15-20 km. Maximum igneous crustal thickness was found to be about 18 km on both of the Euromargins profiles across the outer Vøring Plateau, which is 5-7 km less than reported from older surveys in the area. Lower crustal P-wave velocities of up to 7.3 km s-1 were found at the bottom of the igneous crust here, similar to earlier studies. Magmatic underplating of continental crust was for the first time identified at the Lofoten-Vesterålen margin. At 2 km thickness this is a third of what is typical for the Vøring Plateau, and oceanic crustal thickness adjacent to the continent is close to normal, both showing the distal location of this part of the margin to the Iceland hotspot influence. Continental breakup appears to occur at least 1 M.y. later here than on the Møre Margin to the south. A previously unknown episode of magmatic underplating of oceanic crust off the Vøring Plateau was also identified, creating an igneous crust up to 15 km thick. This episode is completely unrelated to the breakup magmatism, but belongs to a family of Neogene intra-plate magmatism observed in the North Atlantic. The underplating was dated from the inversion of overlying sedimentary strata in the oceanic basin to be Late Miocene.

• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2006). Continental breakup and magmatism at the mid-Norwegian margin, Euromargins 2003 OBS Experiment. Vis sammendrag

  The continental margin off mid-Norway is a volcanic passive margin created during the earliest Eocene, and large volumes of magmatic rocks were emplaced during and a few M.y. after continental breakup. In 2003, an ocean bottom seismometer/hydrophone survey was acquired on the Vøring and Lofoten-Vesterålen Margins. The main targets are continental breakup processes, early seafloor spreading, and along-margin variation of magma productivity. The P-wave data were modeled by a combined forward ray-tracing and inversion into 2D velocity-depth models. The continent-ocean transition zone is usually well defined as a rapid increase of P-wave velocities at mid- to lower-crustal levels. This transition may occur over a distance of only 15-20 km. Maximum igneous crustal thickness was found to be about 18 km on both of the Euromargins profiles across the outer Vøring Plateau, which is 5-7 km less than reported from older surveys in the area. Lower crustal P-wave velocities of up to 7.3 km s-1 were found at the bottom of the igneous crust here, similar to earlier studies. Magmatic underplating of continental crust was for the first time identified at the Lofoten-Vesterålen margin. At 2 km thickness this is a third of what is typical for the Vøring Plateau, and oceanic crustal thickness adjacent to the continent is close to normal, both showing the distal location of this part of the margin to the Iceland hotspot influence. In the absence of an early spreading axis jump, continental breakup must have occurred 1-2 M.y. later here than on the Møre Margin to the south. A previously unknown episode of magmatic underplating of oceanic crust off the Vøring Plateau was also identified, creating an igneous crust up to 15 km thick. This episode is completely unrelated to the breakup magmatism, but belongs to a family of Neogene intra-plate magmatism observed in the North Atlantic. The underplating was dated from the inversion of overlying sedimentary strata in the oceanic basin to be Late Miocene.

• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2006). Continent-ocean transition at the northern Vøring Margin, Norway, Euromargins 2003 OBS Experiment. Vis sammendrag

  The continental margin off mid-Norway is a volcanic passive margin created during the earliest Eocene, and large volumes of magmatic rocks were emplaced during and a few M.y. after continental breakup. In 2003, an ocean bottom seismometer/hydrophone survey was acquired on the Vøring and Lofoten-Vesterålen Margins. The main targets are continental breakup processes, early seafloor spreading, and along-margin variation of magma productivity. The profile presented here is one of five profiles from the survey crossing the continent-ocean boundary. It crosses the northern part of the Vøring Plateau and continues into the oceanic basin out to magnetic anomaly 21 (~47 Ma). The P-wave data were modeled by a combined forward ray-tracing and inversion into a 2D velocity model. Strong lower crustal reflectivity in the thick igneous section imparted ambiguity on Moho interpretation from the OBS/H data. Gravity modeling was used interactively with the ray-tracing to obtain a consistent model. The forward gravity model was corrected by a lithospheric mantle density model based on estimated thermal expansion. The thermal model was calculated by a 2D finite-element program, using the opening history of the oceanic basin. This procedure removed a ~70 mGal regional misfit, and the final fit between observed and calculated gravity is good. Also upper mantle reflectivity is abundant under the thick igneous crust, limited mostly to a zone 2-4 km below the Moho. This indicates a Moho transition zone where mafic and ultramafic rocks interfinger. The profile shows a rapid transition over a distance of 15-20 km from continent to oceanic crust (COT), similar to earlier results. Maximum igneous crustal thickness was found to be 18 km, and from the COT the thickness decreases to ~6.5 km over a distance of 120 km, indicating magmatism abating over a period of at least ~6 M.y. after continental breakup. Lower crustal P-wave velocities of up to 7.3 km s-1 were found at the bottom of the crust. Combined with modeling of the S-wave data, we conclude that the crust is primarily of igneous origin here, though some continental contamination may exist at middle-lower crustal levels in a ~30 km wide zone underneath the continental slope.

• Breivik, Asbjørn Johan; Faleide, Jan Inge & Mjelde, Rolf (2006). MORB-hijacking by the Iceland Plume. Vis sammendrag

  The Iceland plume is one of the prime examples supporting the mantle plume theory, i.e., cooling of the Earth’s interior by localized large vertical mass transport. The plume caused pre-breakup and voluminous breakup magmatism on the North Atlantic continental margins, and formed an aseismic ridge from the continental margins to Iceland. According to theory, the plume initially had a broad head affecting a region ~2000 km wide, while a narrow, long-lived trailing stem interacted with the seafloor spreading to create the exceptionally thick igneous crust of Iceland, and to drive asthenosphere zonation away from Iceland to create V-shaped ridges in the oceanic crust around the spreading axes. However, there are centres of magmatism at distance from the plume, spanning from Miocene to recent, which do not fit with the plume theory. Here we present new data to document an unexpected province of diffuse Late Miocene magmatic underplating of older oceanic crust north of the Aegir Ridge, an extinct seafloor spreading axis in the Norway Basin. Based on correlation between the province and the extinct axis, and similarity to the region northeast of the present spreading on the Kolbeinsey Ridge north of Iceland, we present a new model of plume - spreading ridge interaction to explain these two magmatic provinces: The asthenosphere flow out from Iceland ’hijacks’ deeper, low-degree partially molten asthenosphere regions created underneath the spreading ridges and carry these across the terminating fracture zones, to subsequently add to the base of the oceanic crust or to build seamounts.

• Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf & Tsikalas, Filippos (2006). Continental breakup and magmatic development of the mid-Norwegian margin, Euromargins 2003 OBS Experiment. Vis sammendrag

  The continental margin off mid-Norway is a volcanic passive margin created during the earliest Eocene, and large volumes of magmatic rocks were emplaced during and a few M.y. after continental breakup. In 2003, an ocean bottom seismometer/hydrophone survey was acquired on the Vøring and Lofoten-Vesterålen Margins. The main targets are continental breakup processes, early seafloor spreading, and along-margin variation of magma productivity. The P-wave data were modeled by a combined forward ray-tracing and inversion into 2D velocity-depth models. The continent-ocean transition zone is usually well defined as a rapid increase of P-wave velocities at mid- to lower-crustal levels. This transition may occur over a distance of only 15-20 km. Maximum igneous crustal thickness was found to be about 18 km on both of the Euromargins profiles across the outer Vøring Plateau, which is 5-7 km less than reported from older surveys in the area. Lower crustal P-wave velocities of up to 7.3 km s-1 were found at the bottom of the igneous crust here, similar to earlier studies. Magmatic underplating of continental crust was for the first time identified at the Lofoten-Vesterålen margin. At 2 km thickness this is a third of what is typical for the Vøring Plateau, and oceanic crustal thickness adjacent to the continent is close to normal, both showing the distal location of this part of the margin to the Iceland hotspot influence. Continental breakup appears to occur at least 1 M.y. later here than on the Møre Margin to the south. A previously unknown episode of magmatic underplating of oceanic crust off the Vøring Plateau was also identified, creating an igneous crust up to 15 km thick. This episode is completely unrelated to the breakup magmatism, but belongs to a family of Neogene intra-plate magmatism observed in the North Atlantic. The underplating was dated from the inversion of overlying sedimentary strata in the oceanic basin to be Late Miocene.

• Breivik, Asbjørn Johan & Mjelde, Rolf (2006). Seismic evidence for the Barents Sea - Svalbard Caledonides. Vis sammendrag

  The western Barents Sea and the Svalbard archipelago share a common history of Caledonian basement formation and subsequent sedimentary deposition. Rocks from the period are accessible on Svalbard, but studies of the near offshore areas rely on seismic data and shallow drilling. Offshore mapping is reliable down to the Permian sequence, but multichannel reflection seismic (MCS) data does not give a coherent picture of older stratigraphy. A survey of ten Ocean Bottom Seismometer (OBS) profiles was collected around Svalbard in 1998. Modeling the data by ray-tracing gives whole-crust depth and velocity transects. Results show a highly variable thickness of pre-Permian sedimentary strata. Depth-to-basement and -Moho maps for two areas south of and southwest of Svalbard were produced from this survey. The observed gravity can in some parts of the platform be directly related to velocity variations in the crystalline crust, but often not to basement or Moho depth. The area around the Olga Basin - Sentralbanken High southeast of Svalbard was one of the targets for the survey, and combined velocity and gravity modeling of the OBS data and results, show crustal roots associated with heterogeneous crystalline crust. The area is very similar to the Ural suture zone, and is the first direct indication for an eastern continuation of the Svalbard Caledonides through the Barents Sea. The other target area is located between Bjørnøya and Svalbard, where older deep MCS profiles indicate a westwards dipping suture zone. The OBS data shows that the suture zone is associated with a strong P-wave velocity contrast from east to west. Supported by modeling of the S-wave and gravity data, we conclude that this corresponds to a change from mafic to more felsic composition. Two of the profiles were shot coincident with earlier MCS lines, confirming the crustal root imaged earlier. Combined, these different seismic datasets indicate both a continuous basement high and crustal root trending towards the Billefjorden Fault Zone (BFZ) onshore Svalbard. The eastern side of the BFZ correlates closely with coincident positive gravity and magnetic anomalies on western Ny Friesland, originating from an antiform with high-grade metamorphic Caledonian rocks. A double linear magnetic anomaly appears on the BFZ trend south of Spitsbergen, sub-parallel and located 10-50 km west of the crustal root. Based on this correlation, we propose that the suture or major thrust zone seen south of Svalbard correlates to the BFZ. The preservation of the relationship between the crustal suture, the crustal root, and upper mantle reflectivity south of Svalbard, challenges the large-offset, post-collision sinistral transcurrent movement on the BFZ and other trends proposed in the literature. Also, the seismic data south of Svalbard does not show clear signs of major lateral offsets, as seen in deep seismic data around the British Isles. We conclude that the main Caledonide sutures branched to continue both through Svalbard and through the eastern Barents Sea by collision with one or more microplates caught between Laurentia and Baltica.

• Breivik, Asbjørn Johan; Mjelde, Rolf & Faleide, Jan Inge (2006). Magma-starved seafloor accretion in the Norway Basin caused by the Iceland hotspot. Vis sammendrag

  The Norway Basin was initiated by continental breakup between northern Europe and Greenland/Jan Mayen in the earliest Eocene (~54Ma). Being part of the North Atlantic Igneous Province, continental breakup and early seafloor spreading produced voluminous magmatism, which subsided as seafloor spreading progressed. An ocean bottom seismometer (OBS) profile acquired in the year 2000 from the Norwegian Møre margin to the extinct spreading axis of the Aegir Ridge was used to estimate variations in magma productivity as the oceanic basin evolved. Due to low magnetic data coverage, a satellite derived gravity map proved suitable to reinterpret the East Jan Mayen Fracture Zone (EJMFZ) system, but no other fracture zones could be identified within the Norway Basin. The revised EJMFZ trace was used to re-evaluate spreading in the Norway Basin, which appears more asymmetric than previously believed, being condensed mostly on the southwestern side. The magnetic track recorded along the OBS profile was used to identify magnetic seafloor spreading anomalies by forward modeling, and projected onto synthetic flow lines half spreading rates were derived along-profile. Maximum rate was above 3 cm/a between A24A and A24b, falling off to ~0.7 cm/a (ultra-slow) by C20 (42.7 Ma) which lasted to the Late Oligocene (25-28 Ma) termination of seafloor spreading. Breakup magmatism created oceanic crust up to 10-11 km thick, tapering down to thin crust by C23 time (51.4 Ma); the increased melt potential was thus spent ~2.5 Ma after continental breakup. While oceanic crust created during ultra-slow spreading is thin (3.9 km), crust created during slow spreading is also thinner than the world average (5.3 vs. 7.1 km), indicating a somewhat depleted mantle source. A V-shaped pattern seen in the gravity field only around the northern part of the Aegir Ridge corresponds to increased crustal thickness in the OBS model, demonstrating Middle Eocene-Early Oligocene northeast migration of asthenosphere zones with slightly increased melt production at a speed of 0.3-0.6 cm/a. The thin crust and lack of fracture zones in the Norway Basin is typical for ultra-slow seafloor spreading, even if much of it was created during slow spreading (~1.5 cm/a half rate). This character may have developed not despite the closeness to the Iceland Hotspot, but because of it, as mantle partially depleted by high magma production during the construction of the aseismic Iceland-Faeroe Ridge to the south was transported to the northeast to feed oceanic accretion. The southern part of the Norway Basin lacks V-shaped ridges and the Aegir Ridge has a deeper axial valley, indicating a lower magma budget than in the north, consistent with this model.

• Faleide, Jan Inge; Mjelde, Rolf; Tsikalas, Filippos; Breivik, Asbjørn Johan; Raum, Thomas; Wilson, Jonas & Eldholm, Olav (2006). A regional 3D model of the crustal architecture and evolution of the mid-Norwegian continental margin.
• Faleide, Jan Inge; Tsikalas, Filippos; Breivik, Asbjørn Johan; Wilson, Jonas; Engen, Øyvind & Eldholm, Olav (2006). Late Mesozoic-Cenozoic evolution of the NE Atlantic region and links to the Arctic.
• Faleide, Jan Inge; Wilson, Jonas; Mjelde, Rolf; Ritzmann, Oliver & Breivik, Asbjørn Johan (2006). Crustal structure and deep basin configuration - key observations and modelling constraints.
• Ljones, Frode; Breivik, Asbjørn Johan; Mjelde, Rolf & Faleide, Jan Inge (2006). Stacking of wide-angle OBS data as multichannel data – outer Vøring Margin.
• Mjelde, Rolf; Breivik, Asbjørn Johan & Faleide, Jan Inge (2006). Crustal profile across the North Atlantic.
• Mjelde, Rolf; Breivik, Asbjørn Johan & Faleide, Jan Inge (2006). Crustal transect across the North Atlantic.
• Mjelde, Rolf; Breivik, Asbjørn Johan & Raum, Thomas (2006). Sub-basalt imaging on the mid-Norwegian margin, using OBS data.
• Ritzmann, Oliver; Faleide, Jan Inge; Breivik, Asbjørn Johan & Mjelde, Rolf (2006). Tectonic development and temperature history of the Vøring area, mid Norway - Task Seismic wave field modelling along deep-seismic transects.
• Tsikalas, Filippos; Breivik, Asbjørn Johan; Faleide, Jan Inge; Mjelde, Rolf & Eldholm, Olav (2006). Crustal structure, continental breakup and magmatism at the Lofoten-Vesterålen margin, off Norway, constrained by the Euromargins 2003 OBS Experiment.
• Tsikalas, Filippos; Breivik, Asbjørn Johan; Faleide, Jan Inge; Raum, Thomas; Mjelde, Rolf & Eldholm, Olav (2006). Crustal structure of the Lofoten-Vesterålen margin, off Norway, constrained by new OBS data.
• Tsikalas, Filippos; Breivik, Asbjørn Johan; Faleide, Jan Inge; Raum, Thomas; Mjelde, Rolf & Eldholm, Olav (2006). OBS data constrain the crustal structure of the Lofoten-Vesterålen margin, off Norway.
• Wilson, Jonas; Raum, Thomas; Mjelde, Rolf; Faleide, Jan Inge; Breivik, Asbjørn Johan; Murai, Yoshio & Flüh, Ernst (2006). Crustal structure and composition beneath the Trøndelag Platform, mid-Norwegian margin, derived from wide-angle seismic and gravity data.
• Breivik, Asbjørn Johan; Faleide, JI & Mjelde, Rolf (2005). Late Miocene magmatic underplating of the oceanic crust at the outer Vøring Margin, Norway,Euromargins 2003 OBS experiment.
• Breivik, Asbjørn Johan; Mjelde, Rolf & Faleide, Jan Inge (2005). Continental Breakup Magmatism and Transition to Hot-Spot Influenced Seafloor Spreading From the Moere Margin to the Norway Basin.
• Breivik, Asbjørn Johan; Mjelde, Rolf & Faleide, Jan Inge (2005). Slow to ultraslow seafloor spreading in the Norway Basin under influence of the Iceland hotspot.
• Breivik, Asbjørn Johan; Mjelde, Rolf & Faleide, JI (2005). OBS 2003 survey: P-wave modelling of Profile 11 at the Vøring Margin.
• Breivik, Asbjørn Johan; Mjelde, Rolf & Faleide, JI (2005). OBS 2003 survey: complete modelling of Profile 10 at the outer Vøring Margin.
• Breivik, Asbjørn Johan; Mjelde, Rolf & Faleide, JI (2005). Slow to ultraslow seafloor spreading in the Norway basin under influence of the Iceland hotspot.

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