The Early Carboniferous Mageroy dykes, northern Norway: palaeomagnetism and palaeogeography

Research output: Contribution to journalArticle

Abstract

Palaeomagnetic data from the 337 Ma Mageroy dykes (northern Norway) are of exceptionally high quality, and a positive contact test along with an existing regional result from the Silurian Honningsvag Igneous Suite attests to a primary Early Carboniferous magnetic signature. The palaeomagnetic pole (S 14.8degrees, E320.1degrees, dp/dm = 4.4/8.6degrees) is the first Early Carboniferous pole from Baltica, and implies that northernmost Norway-Greenland, the Barents Sea and Svalbard were located at tropical to low northerly latitudes at this time. Northward drift during Carboniferous times (5-6 cm/yr) as demonstrated from palaeomagnetic data is also reflected in the sedimentary facies in the Barents Sea realm, that is, a change from tropical (Early Carboniferous) to subtropical (20-30degrees N) carbonates and evaporites in the Late Carboniferous. The Mageroy dykes are continental tholeiites which intruded into a set of NW-SE-trending normal faults parallel to the Trollfjorden-Komagelva Fault Zone and the Mageroysundet Fault immediately to the north and south of Mageroya, respectively. These, and many other NW-SE-trending faults (onshore and offshore), were active during Late Palaeozoic extension, and the dykes were probably contemporaneous with the earliest syn-rift sedimentation in the Barents Sea (for example, the Nordkapp Basin).

Details

Authors
  • RJ Roberts
  • TH Torsvik
  • TB Andersen
  • Emma Rehnström
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Geology

Keywords

  • palaeogeography, Carboniferous, Norway, palaeomagnetism
Original languageEnglish
Pages (from-to)443-451
JournalGeological Magazine
Volume140
Issue number4
Publication statusPublished - 2003
Publication categoryResearch
Peer-reviewedYes