T361 Paleomagnetism of the Americas and Europe and Their Surroundings: Questions Answered, Questions Remaining, and Questions to Come (Posters)

Wednesday, 30 October 2013
9:00 AM - 6:30 PM
Hall D

PALEOMAGNETIC STUDIES OF THE MESOPROTEROZOIC UNITS IN SW FINLAND WITH IMPLICATIONS FOR A NORTHERN EUROPE – NORTH AMERICA (NENA) CONNECTION WITHIN NUNA SUPERCONTINENT

Paper number: T361-7
Program: Technical Sessions
Time: 9:00 AM – 6:30 PM

Authors

Abstract

Paleoproterozoic supercontinent Nuna (Columbia, Hudsonland) has been proposed by several authors [e.g. 1, 2, 3]. Many recent reconstructions of this supercontinent support, within the analytical uncertainties, that the core of Nuna was formed by a single NENA (Northern Europe – North America) juxtaposition between Baltica and Laurentia between ca. 1.75 Ga and ca. 1.27 Ga [4, 5, 6]. However, recent paleomagnetic data from ca. 1.63 Ga Melville Bugt dykes in Greenland does not support that fit [7]. To address these concerns, we present new paleomagnetic data from Late Mesoproterozoic diabase dyke swarms (Satakunta: 1565 Ma and Åland: 1577-1540 Ma) and from Mesoproterozoic Satakunta sandstone located in SW Finland. A dual-polarity, high-stability remanence component from the dated 1565 Ma Satakunta dyke swarm with the paleopole of Plat=29.3°N, Plon=188.1°E (A95 = 6.6°), is confirmed to be primary by positive baked-contact tests, and suggests that NENA was valid also at 1.63-1.54 Ga [8, 9]. Comparable paleopole (Plat=26.8°N, Plon=173.5°E; A95 = 5.7°) from the ca. 1.6 Ga Satakunta sandstone gives support to this result.

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