New and revised palaeomagnetic secular variation records from post-glacial volcanic materials in New Zealand

作者：Greve Annika^*; Turner Gillian M

来源：Physics of the Earth and Planetary Interiors, 2017, 269: 1-17.

DOI：10.1016/j.pepi.2017.05.009

• Palaeomagnetic secular variation
• New Zealand
• SW Pacific
• Absolute palaeointensity
• Taupo Volcanic Zone

Global databases suffer from a paucity of palaeomagnetic secular variation (PSV) data from the SW Pacific region and are often affected by inconsistencies in data quality, or available age control of the sampled units. Here we present new PSV records obtained from post-glacial (<= 15 kyrs BP) volcanic materials (mainly lavas) from New Zealand. The new dataset incorporates a compilation and. critical assessment of all previous discrete PSV data and their age controls, and the results of new sampling in the Taupo Volcanic Zone. The overall dataset includes 23 directional and 10 absolute palaeointensity records primarily from lavas of rhyolitic or andesitic composition. Age constraints on the rhyolitic lavas are available from correlation with distal, radiocarbon dated tephra deposits, age controls on the andesites from field relationships or from Ar-40/Ar-39 dating. Directional swings, ranging from 326.5 degrees to 26.0 degrees declination and -81.4 to -46.3 degrees inclination and intensity variations from 37.0 to 71.6 mu T, fall well into the range of PSV expected for this time-frame in New Zealand and reproduce features of continuous sediment records.

• 出版日期2017-8