= Solution
\b[Repeated assembly and dispersal are supported by mutually consistent <paleogeography>, <paleomagnetism>, dated collision belts and subsequent rifted margins.] A useful reconstruction must explain both former connections and later separation, at the same geological ages.
For the youngest well-constrained example, <Pangaea>, matching continental outlines become more compelling when the fit uses the continental edges rather than mobile modern shorelines. More discriminating evidence includes the continuation of <mountain belts>, <sedimentary successions> and distinctive basement rocks across now-separated continents. Correlated terrestrial <fossil assemblages> and the distribution of <glacial deposits> become geographically coherent when the continents are restored. Each observation alone can have alternatives, but a single reconstruction that satisfies several independent tests is much harder to explain by coincidence.
For older examples, the most useful surviving record lies within the <cratons> and their margins. Dated <suture zones>, <ophiolites>, <metamorphic belts> and <pressure-temperature-time paths> document former ocean closure and <continental collision>. Restoring now-separated belts to continuity tests an assembly. Subsequent <continental rifting>, matching <dike swarms>, <large igneous provinces> and the transition to <passive margins> test its breakup. <Uranium-lead dating> of <zircon>, including <detrital zircon> populations and <sedimentary provenance>, helps establish whether the proposed connections existed at the same time.
<Paleomagnetism> supplies an independent quantitative test. A primary <remanent magnetization> constrains ancient latitude and orientation. After a proposed relative rotation brings two blocks together, compatible <apparent polar wander paths> over an interval support their travelling together; divergence of those paths can document separation. <Radiometric dating>, a <paleomagnetic fold test> and a <paleomagnetic reversal test> help identify primary records and distinguish them from <remagnetization>. There remain important ambiguities: conventional <paleomagnetism> does not fix absolute longitude, and sparse ages, later deformation and <true polar wander> complicate a reconstruction.
The broad succession is <Columbia (supercontinent)> or <Nuna>, assembled mainly around 1.9–1.6 billion years ago; <Rodinia>, assembled mainly around 1.1–0.9 billion years ago and dispersed in stages during the later <Proterozoic>; and <Pangaea>, assembled by roughly 300 million years ago and breaking apart from roughly 200 million years ago. These are broad intervals rather than synchronous global events. A quantitative <Nuna> reconstruction combines <paleomagnetism> with the histories of continental margins rather than relying only on matching rock ages.<Assembly and breakup of the core of Paleoproterozoic-Mesoproterozoic supercontinent Nuna by David A. D. Evans and Ross N. Mitchell>[pp. 443–446, reconstruction of the Nuna core and tests using paleomagnetic and tectonostratigraphic records.]{ref}
Repeated global peaks in dated <magmatism> and <metamorphism> offer supporting evidence, but cannot prove a <supercontinent cycle> by themselves: <erosion>, burial and preferential preservation also change the observed age distribution. The persuasive case is the recurrence of dated assembly–breakup sequences in different <continental configurations>, with stronger geometric constraints for <Pangaea> than for the older <supercontinents>. A <Wilson cycle> describes an individual ocean's opening and closure; a <supercontinent cycle> concerns the much larger-scale continental assembly and dispersal.
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