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Palaeomagnetic investigation of Lower Ordovician limestone in the vicinity of St. Petersburg yields a pole position at latitude 34.7°N, longitude 59.1°E (dp/dm=5.7°/6.4°). A probable primary remanence origin is supported by the presence of a field reversal. The limestone carries one other remanent magnetization component associated with a Mesozoic remagnetization event. An apparent polar wander path is compiled for Baltica including the new result, ranging in age from Vendian to Cretaceous. Ages of the published Lower to mid‐Palaeozoic palaeomagnetic pole positions are adjusted in accordance with the timescale of Tucker & McKerrow (1995). The new Arenig result is the oldest of a series of Ordovician and Silurian palaeomagnetic pole positions from limestones in the Baltic region. There are no data to constrain apparent polar wander for the Tremadoc, Cambrian and latest Vendian. If the Fen Complex results, previously taken to be Vendian in age (c. 565 Ma), are reinterpreted as Permian remagnetizations, an Early Ordovician–Cambrian–Vendian cusp in the polar wander path for Baltica is eliminated. The apparent polar wander curve might then traverse directly from poles for Vendian dykes on the Kola peninsula (c. 580 Ma) towards our new Arenig pole (c. 480 Ma). The consequence of this change in terms of the motion of Baltica in Cambrian times is to reduce significantly a rotational component of movement. The new Arenig pole extends knowledge of Ordovician apparent polar wander an increment back in time and confirms the palaeolatitude and orientation of Baltica in some published palaeogeographies. Exclusion of the Fen Complex result places Baltica in mid‐ to high southerly latitudes at the dawn of the Palaeozoic, consistent with faunal and sedimentological evidence but at variance with some earlier palaeomagnetic reconstructions.

A new version of the Global Paleomagnetic Database—GPMDB V 4.6—is available now at the Tectonics Special Research Centre of the University of Western Australia Web site (http://www.tsrc.uwa.edu.au/). This version contains 9259 paleomagnetic poles from 7513 rock units published in 3673 articles up to December 2004 inclusive. This version has also been completely updated using the latest International Stratigraphic Chart published by the International Commission on Stratigraphy (ICS) on its Web site (www.stratigraphy.org). This new timescale is significantly different from the timescale which has been used in the database for the past decade. All entries in the database based on biostratigraphic ages have had their absolute minimum and maximum age limits revised according to this new scale. Therefore, users of the database who have compiled their own files based on the old database should be aware that the assigned absolute ages have now changed.

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