Article ID Journal Published Year Pages File Type
6428498 Earth and Planetary Science Letters 2015 14 Pages PDF
Abstract
Understanding the behavior of enigmatic geomagnetic traits such as the Levant intensity high is currently challenged by a lack of full vector records of regional variations in the geomagnetic field. Here we apply the recently proposed multi-method paleointensity approach to a suite of 19 lavas from the Canary Islands dating between ∼4000 BC and 1909 AD. Our new record reveals high paleointensities (VADMs >120 ZAm2) coinciding with and shortly after the peak in geomagnetic intensity in the Levant at ∼1000 BC. Furthermore our data suggests a westward movement of this geomagnetic phenomenon at a rate of 6.7-12° per century. In addition to IZZI-Thellier, microwave-Thellier and the multi-specimen method, the calibrated pseudo-Thellier method is an important part of the multi-method paleointensity approach. The calibration of this relative paleointensity method was derived from a suite of Hawaiian lavas; it is improved with the results of the Canarian cooling units. Pseudo-Thellier results from samples with very low Curie temperature (<150 °C), however, cannot be reliably converted to absolute paleointensity estimates. The multi-method paleointensity approach yielded a reliable estimate for ∼60% of the flows sampled - an unusually high success rate for a paleointensity study involving lavas.
Related Topics
Physical Sciences and Engineering Earth and Planetary Sciences Earth and Planetary Sciences (General)
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