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Secular variation and reversals in a composite 2.5 km thick lava section in central Western Iceland

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Abstract

The direction and intensity of primary remanence has been measured in oriented specimens from 367 lava flows of Late Miocene age in Western Iceland. The lavas which were sampled in 8 overlapping profiles, were generally good material for paleomagnetic measurements. In a 2500-m composite section, at least 15 reversals of polarity and several excursions are recorded. The mean remanence direction and other overall paleomagnetic parameters for the present collection of lavas are similar to those found elsewhere in Iceland. The average rate of buildup of this lava pile was rather low and possibly episodic. Hence, correlations to the geomagnetic polarity time scale and to polarity patterns in other composite sections mapped in Iceland are not straightforward.

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Correspondence to Leó Kristjánsson.

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Kristjánsson, L., Jóhannesson, H. Secular variation and reversals in a composite 2.5 km thick lava section in central Western Iceland. Earth Planet Sp 51, 261–276 (1999) doi:10.1186/BF03352230

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Keywords

  • Remanence
  • Rift Zone
  • Secular Variation
  • Polarity Zone
  • Composite Section