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Incoming links: Siberian craton
Ross N. Mitchell Created 2026-10-25 Updated 2026-11-05
Ross N. Mitchell studies ancient continental configurations using paleomagnetism and the geological record of supercontinents. In a 2011 paper with David A. D. Evans, he combined dated magnetic-pole records with tectonic and stratigraphic correlations to reconstruct the core of Nuna. The reconstruction fitted the Siberian craton, Laurentia and Baltica together for an interval roughly 1.9–1.3 billion years ago and tested that fit against the histories of their margins.[ref]
Assembly and breakup of the core of Paleoproterozoic-Mesoproterozoic supercontinent Nuna by David A. D. Evans and Ross N. Mitchell. Abstract and Figure 1, pp. 443–444: quantitative reconstruction and independent geological correlations
This is a comparison between several kinds of evidence. Matching apparent polar wander paths constrains relative continental motion, while dated evidence of mountain building and continental-margin histories test whether the proposed neighbors experienced compatible events. Divergence between those records can indicate assembly or separation. The paper presents a particular reconstruction to be tested against further observations; its detailed fit is not implied merely by naming a supercontinent.
A researcher in paleomagnetism and supercontinent histories. Institutional profile: igg.cas.cn/sourcedb_igg_cas/cn/zjrck/yjy/201912/t20191219_5460988.htm
Siberian craton 2026-11-05
The Siberian craton is an ancient, long-lived continental block in northern Asia. Its comparatively stable interior preserves a record that can be used to reconstruct earlier continental configurations, distinct from younger tectonic belts around its margins.
A reconstruction combines dated rock units, structural relationships and paleomagnetic poles. The poles constrain latitude and orientation within a magnetic-field model but generally leave a longitude ambiguity. Consequently, placing the Siberian craton relative to Laurentia or Baltica requires additional geological evidence; a single magnetic direction cannot uniquely determine a complete ancient world map.