HUSCAP logo Hokkaido Univ. logo

Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Science / Faculty of Science >
Peer-reviewed Journal Articles, etc >

The eastern Jan Mayen microcontinent volcanic margin

Files in This Item:
GJI188-3_798-818.pdf16.18 MBPDFView/Open
Please use this identifier to cite or link to this item:

Title: The eastern Jan Mayen microcontinent volcanic margin
Authors: Breivik, Asbjørn Johan Browse this author
Mjelde, Rolf Browse this author
Faleide, Jan Inge Browse this author
Murai, Yoshio Browse this author →KAKEN DB
Keywords: Controlled source seismology
Continental margins: divergent
Oceanic plateaus and microcontinents
Large igneous provinces
Crustal structure
Magma genesis and partial melting
Issue Date: Mar-2012
Publisher: Blackwell Publishing
Journal Title: Geophysical Journal International
Volume: 188
Issue: 3
Start Page: 798
End Page: 818
Publisher DOI: 10.1111/j.1365-246X.2011.05307.x
Abstract: 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℃ in the north and 90-150℃ in the south.
Rights: The definitive version is available at
Type: article
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)

Submitter: 村井 芳夫

Export metadata:

OAI-PMH ( junii2 , jpcoar_1.0 )

MathJax is now OFF:


 - Hokkaido University