| Summary: | Udgivelsesdato: 2005-11-15 The results of a palaeomagnetic sampling carried out along two vertical profiles (altogether 19 lavaflows, 126 samples) covering the entire stratigraphy of the Talerua Member lavas (~39 Myr old) that outcrop on the island Hareøen are presented and represent some of the youngest volcanism in the West Greenland flood volcanic province. Rock magnetic experiments and microprobe analysis show that the dominant magnetic mineral in all studied lavas is titanomagnetite that has experienced variable amounts of high temperature deuteric oxidation as well as low temperature hydro-thermal oxidation. Based on detailed demagnetisation experiments, well-defined paleomagnetic site-mean directions were isolated from all 19 lavas. The composite profile contains two magnetic polarity zones suggesting a maximum duration of Talerua Member volcanism of ~1.4 Myr. After grouping flows indicating the same remanent magnetic field direction, 13 individual readings of the paleomagnetic fields were obtained. The paleomagnetic pole with coordinates 76.3°N, 201.5°E (A95=7.4°, K=32.7, N=13) is in good accordance with paleomagnetic poles from other continents rotated back to Greenland using plate kinematic rotation poles.
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