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Supercontinent centres. a, Successive post-Rodinia (orange and green open ellipses) and post-Pangaea (light-blue and dark-blue open ellipses) Imin axes are calculated as the poles to great-circle fits of palaeomagnetic poles from Australia at 650–560 Myr ago (orange solid ellipses) and Gondwanaland from 550–490 Myr ago (light-green solid ellipses), and the global running-mean apparent polar wander path for 260–220 Myr ago (light-blue solid ellipses) and 210–90 Myr ago (dark-blue solid ellipses)24. Dark-green poles for later Palaeozoic time from Gondwanaland are displayed but not included in any mean calculation (see text for discussion). b, Successive post-Nuna (red open ellipse) and post-Rodinia (orange open ellipse) Imin axes. Filled red ellipses are poles for Laurentia from 1,165–1,015 Myr ago. Filled orange ellipses are poles for Laurentia rotated from Svalbard at around 800 Myr ago18 (see Methods section for discussion of rotation). All ellipses are projections of cones of 95% confidence. Pole information is listed in Supplementary Table 1, statistical parameters are detailed in Supplementary Table 2, and a version of this figure with the poles numbered to give a sense of age order is provided in Supplementary .
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Traditional models of the supercontinent cycle predict that the next supercontinent--'Amasia'--will form either where Pangaea rifted (the 'introversion' model) or on the opposite side of the world (the 'extroversion' models). Here, by contrast, we develop an 'orthoversion' model whereby a succeeding supercontinent forms 90° away, within the great c...
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Context 1
... Rodinia interval is marked by rapid, oscillatory continental motions that have been interpreted as TPW during the time of super- continent amalgamation at around 1,100-1,000 Myr ago 5,21 and break-up at around 800 Myr ago 18,22 (Fig. ...
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... note that early Palaeozoic kimberlites and large igneous provinces, particularly widespread in Siberia and Australia, reconstruct within or near the idealized I min circles in our model, consistent with their derivation from plume-generating zones in the deep mantle 16 . At 600 Myr ago, just before Gondwanaland assembly, Australia is reconstructed relative to the I min axis according to its palaeomagnetic data (Supplementary Table 2), as is Laurentia, assuming that TPW is responsible for the bulk of variance in its palaeomagnetic poles 26 . At 800 Myr ago, we reconstructed Rodinia, according to ref. 19, around Laurentia, which is fixed to the I min axis by its restored Svalbard palaeomagnetic data. ...
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... each of the six time intervals, I min is calculated as the pole to the best-fitted great circle to a swath of palaeomagnetic poles ( Fig. 2; Supplementary Table 1) relative to a given reference frame during proposed intervals of TPW: 200-90 Myr relative to South Africa, 260-220 Myr relative to South Africa, 550-490 Myr rela- tive to South Africa, 650-560 Myr relative to South Africa, 805-790 Myr relative to Laurentia, and 1,165-1,015 Myr relative to Laurentia ...
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... each of the six time intervals, I min is calculated as the pole to the best-fit great-circle to a swath of palaeomagnetic poles ( Fig. 2; Supplementary Table 1) relative to a given reference frame during proposed intervals of TPW: 200-90 Myr relative to South Africa, 260-220 Myr relative to South Africa, 550-490 Myr rela- tive to South Africa, 650-560 Myr relative to South Africa, 805-790 Myr relative to Laurentia, and 1,165-1,015 Myr relative to Laurentia ...
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... relative to South Africa, 550-490 Myr rela- tive to South Africa, 650-560 Myr relative to South Africa, 805-790 Myr relative to Laurentia, and 1,165-1,015 Myr relative to Laurentia (Supplementary Table 2). We limit our calculation of Rodinia's I min to the 650-360-Myr APW path for Gondwanaland and Australia alone before the Early Cambrian period (Fig. 2a). Poles from Gondwanaland are rotated into South African coordinates (Supplementary Table 4). The Rodinian I min for Laurentia (Fig. 2b) is affected by the rotation of Svalbard to Laurentia 18,35 but our results do not change signifi- cantly if geologically reasonable juxtapositions are considered. Confidence limits on the poles to ...
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... and 1,165-1,015 Myr relative to Laurentia (Supplementary Table 2). We limit our calculation of Rodinia's I min to the 650-360-Myr APW path for Gondwanaland and Australia alone before the Early Cambrian period (Fig. 2a). Poles from Gondwanaland are rotated into South African coordinates (Supplementary Table 4). The Rodinian I min for Laurentia (Fig. 2b) is affected by the rotation of Svalbard to Laurentia 18,35 but our results do not change signifi- cantly if geologically reasonable juxtapositions are considered. Confidence limits on the poles to great circles (Supplementary Table 1) are calculated using the software package of ref. 36 employing two alternative statistical methods ...
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Citations
... TPW currently happening today, documented with astronomical observations for over a century and with satellites for several decades, occurs at a rate of~1°Myr −1 and is thought to be caused by a combination of Holocene deglaciation and longer timescale mantle processes [3][4][5][6] . Comparison of successive high-quality palaeomagnetic poles is an effective means of testing TPW and multiple episodes of large-amplitude TPW spanning the Palaeoproterozoic to the Cretaceous have been revealed [7][8][9][10][11][12] . However, the occurrence of TPW in the geologic past remains highly controversial [13][14][15] . ...
The reorientation of Earth through rotation of its solid shell relative to its spin axis is known as True polar wander (TPW). It is well-documented at present, but the occurrence of TPW in the geologic past remains controversial. This is especially so for Late Jurassic TPW, where the veracity and dynamics of a particularly large shift remain debated. Here, we report three palaeomagnetic poles at 153, 147, and 141 million years (Myr) ago from the North China craton that document an ~ 12° southward shift in palaeolatitude from 155–147 Myr ago (~1.5° Myr⁻¹), immediately followed by an ~ 10° northward displacement between 147–141 Myr ago (~1.6° Myr⁻¹). Our data support a large round-trip TPW oscillation in the past 200 Myr and we suggest that the shifting back-and-forth of the continents may contribute to the biota evolution in East Asia and the global Jurassic–Cretaceous extinction and endemism.
... Marine magnetic anomalies enable the determination of relative palaeolongitude back to the time of Pangaea breakup (~200 Ma), but they cannot constrain absolute palaeolongitude. Other attempts to constrain palaeolongitude in deeper time remain controversial (Mitchell et al., 2012;. This has broad implications for palaeobiological studies such as those reconstructing organisms' geographic range sizes in deep time (e.g. ...
Global plate models (GPMs) aim to reconstruct the tectonic evolution of the Earth by modelling the motion of the plates and continents through time. These models enable palaeobiologists to study the past distribution of extinct organisms. However, different GPMs exist that vary in their partitioning of the Earth's surface and the modelling of continental motions. Consequently, the preferred use of one GPM will influence palaeogeographic reconstruction of fossil occurrences and any inferred palaeobiological and palaeoclimatic conclusion.
Here, using five open‐access GPMs, we reconstruct the palaeogeographic distribution of cell centroids from a global hexagonal grid and quantify palaeogeographic uncertainty across the entire Phanerozoic (540–0 Ma). We measure uncertainty between reconstructed coordinates using two metrics: (1) palaeolatitudinal standard deviation and (2) mean pairwise geodesic distance. Subsequently, we evaluate the impact of GPM choice on palaeoclimatic reconstructions when using fossil occurrence data. To do so, we use two climatically sensitive entities (coral reefs and crocodylomorphs) to infer the palaeolatitudinal extent of subtropical climatic conditions for the last 240 million years.
Our results indicate that differences between GPMs increase with the age of reconstruction. Specifically, cell centroids rotated to older intervals show larger differences in palaeolatitude and geographic spread than those rotated to younger intervals. However, high palaeogeographic uncertainty is also observed in younger intervals within tectonically complex regions (i.e. in the vicinity of terrane and plate boundaries). We also show that when using fossil data to infer the distribution of subtropical climatic conditions across the last 240 Ma, estimates vary by 6–7° latitude on average, and up to 24° latitude in extreme cases.
Our findings confirm that GPM choice is an important consideration when studying past biogeographic patterns and palaeoclimatic trends. We recommend using GPMs that report true palaeolatitudes (i.e. use a palaeomagnetic reference frame) and incorporating palaeogeographic uncertainty into palaeobiological analyses.
... In contrast to these kinematic concepts, Mitchell et al. (2012) tied supercontinent cycles to the geodynamic concept of orthoversion, which relates the amalgamation and breakup of supercontinents to global-scale mantle convection patterns. Orthoversion does not consider supercontinent configuration or the age of oceanic lithosphere but focuses on processes such as coupled supercontinent-mantle harmonics and true polar wander (TPW). ...
... deep mantle expression of a supercontinent). As the downwelling girdle is a dynamic topographical low, there is an overall tendency for the subduction ring as well as the dispersing continents to migrate towards the girdle (Mitchell et al. 2012;Wang et al. 2021;Fig. 3b, c). ...
... The oceans 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 that were closed to form the new supercontinent existed within the continental hemisphere and were enclosed within the subduction ring. As the mantle downwelling girdle is orthogonal to the LLSVP that formed beneath the preceding supercontinent, introversion will always satisfy orthoversion (Mitchell et al. 2012;Wang et al. 2021). Introversion can occur either by migration of the cratons subequatorially (Fig. 3d) or to sub-polar regions along the subduction girdle (Fig. 3e). ...
Supercontinent amalgamation is described by the end-member kinematic processes of introversion - closure of interior oceans; extroversion - closure of exterior oceans; or orthoversion - amalgamation 90° from the centroid of the previous supercontinent. However, supercontinent formations are often ascribed to contradictory mechanisms; for example, Pangea has been argued to have formed by introversion from Pannotia/Gondwana, and extroversion from Rodinia. Conflicting interpretations arise partly from attempting to define oceans as interior or exterior based on paleogeography, or the age of the oceanic lithosphere relative to the time of supercontinent breakup. We define interior and exterior oceans relative to the external subduction ring, and associated accretionary orogens that surround amalgamated supercontinents. All oceans within the continental dominated cell and internal to the subduction ring are interior oceans. The exterior ocean is separated from the interior oceans by the subduction ring and bordered by external accretionary orogens. Wilson cycle tectonics dominate the interior continental cell, conversely, subduction of the exterior ocean is doubly vergent and lacks continent-continent collision. For the exterior ocean to close, the subduction ring must collapse upon itself, leading to the collision of external accretionary orogens. Employing this definition, Rodinia formed by extroversion, but all other supercontinents formed by introversion.
... Pangea's rotation looks centred around an about equatorial axis in northwestern Gondwana ( Figure 7a, c, e). The rotation axis may be further pinpointed to northwestern Africa, as judged from the greatcircle-aligned SNEO and AR pole paths, and may reflect the earth's minimum moment of inertia axis (Steinberger and Torsvik, 2010;Mitchell et al., 2012;Torsvik et al., 2014;Torsvik, 2019). Australia, of all Pangean continents, is at maximum distance from this rotation axis. ...
A long and detailed pole path has been defined from ignimbritic successions across the Tamworth Belt forearc basin of a Carboniferous continental arc in the southern New England Orogen (SNEO) of eastern Australia. Stratigraphic successions spanning about 50 myr have been studied paleomagnetically in 400 sites covering 4500 samples. The Carboniferous SNEO path is thought representative for Australia and Gondwana. Its prominent from-south-over-east-to-north loop with a mid Carboniferous apex differs fundamentally from conventional Australian and Gondwanan Carboniferous pole paths featuring from-south-over-west-to-north loops. The eastern loop of the SNEO path is supported by poles from other workers on the Tamworth Belt. The western loop of conventional paths may reflect unrecognised overprinting and alternative polarity interpretation. Mid-to-latest Carboniferous segments of the SNEO path and of a Carboniferous-to-Permian pole path for the northern Variscan massifs of Armorica (AR) are comparable in shape and length, each spanning more than a hundred degrees of arc. Visual matching of the two pole path segments by rotation around an Euler pole, with the SNEO segment taken as representative for Gondwana and representation of the AR segment tentatively extended to Laurussia, locates Armorica off northwestern Gondwana, and with it Laurussia, in a mid-to-latest Carboniferous Pangea-B configuration. The two mid-to-latest-Carboniferous pole path segments are each bounded by prominent mid Carboniferous and latest Carboniferous-to-earliest/early Permian loops, likely reflecting global tectonic events, dating the Pangea-B configuration as extending from the Sudetic phase to the Asturian phase of the Variscan Orogeny, with transformation to Pangea-A starting likely therefrom. Such a Pangean evolution offers new insights in location of a northern Gondwanan Armorican Spur, causes of the late Carboniferous Hercynian Unconformity and early Permian Pangea-wide extension, and drivers for contemporaneous oroclinal deformation of the Ibero-Armorican Arc and the SNEO. Global movements described by the SNEO and AR pole paths suggest causality between a Visean northern excursion of Gondwana that likely disturbed the earth’s moment-of-inertia, a latest Visean-to-Serpukhovian inertial interchange true polar wander (IITPW) event that led to the Serpukhovian biodiversity crisis and latest Visean-Serpukhovian onset of continental glaciation consolidating the Late Paleozoic Ice Age (LPIA), and the Bashkirian start of the Permo-Carboniferous Reverse Superchron (PCRS).
... We believe that this may be due to a lack of coeval and highresolution data and propose that the oscillation may indicate IITPW events (Evans 2003;Gong & Evans 2022). This is in line with the suggestion of large-amplitude TPW events during the formation of a supercontinent (Evans 1998(Evans , 2003Mitchell et al. 2012Mitchell et al. , 2021Mitchell 2014). (Fig. 8). ...
... 3. The palaeomagnetic data from cratons in Fennoscandia, the Kalahari, Siberia and possibly India indicate a global period of minimal drifting at ca. 1880-1830 Ma, following the period of large craton movements at ca. 2060-1880 Ma. We agree on the previous interpretations of these movements being related to the IITPW events (Mitchell et al. 2010;Antonio et al. 2017;Gong & Evans 2022), thought to be related to the amalgamation of supercontinent (Evans 1998(Evans , 2003Mitchell et al. 2012Mitchell 2014 ...
The Svecofennian gabbro intrusions coincide temporally with the global 2100–1800 Ma orogens related to the amalgamation of the Mesoproterozoic supercontinent Nuna. We provide a new reliable 1891–1875 Ma palaeomagnetic pole for Fennoscandia based on rock magnetic and palaeomagnetic studies on the Svecofennian intrusions in central Finland to fill gaps in the Palaeoproterozoic palaeomagnetic record. By using the new pole together with other global high-quality data, we propose a new palaeogeographic reconstruction at 1885 Ma. This, together with previous data, supports a long-lived relatively stable position of Fennoscandia at low to moderate latitudes at 1890–1790 Ma. Similar stable pole positions have also been obtained for Kalahari at 1880–1830 Ma, Siberia at 1880–1850 Ma, and possibly India at 1980–1775 Ma. A new reconstruction at the beginning of this period indicates the convergence of several cratons at 1885 Ma in the initial stages of the amalgamation of the Nuna supercontinent at low to moderate latitudes. The close proximity of cratons at low to moderate latitudes is further supported by global and regional palaeoclimatic indicators. Stable position of several cratons could indicate a global period of minimal apparent drift at ca. 1880–1830 Ma. Before this period, the global palaeomagnetic record indicates large back-and-forth swings, most prominently seen in the high-resolution 2020–1870 Ma Coronation loops of the Slave craton. These large back-and-forth movements have been explained as resulting from an unstable geomagnetic field or basin- or local-scale vertical-axis rotations. However, the most likely explanation is inertial interchange true polar wander (IITPW) events, which is in line with the suggestion of large amplitude true polar wander events during the formation of the supercontinent.
... From a geodynamic perspective, the closure of the Mozambique Ocean along the EAO can be examined in the context of supercontinent assembly and breakup via introversion, extroversion, or orthoversion 18,19 , which is related to the evolution of the structure of the lower mantle structure beneath Africa 20,21 . Despite the numerous controversies and general lack of highquality palaeomagnetic data during the Late Ediacaran, the paleogeographic evolution leading to the closure of the Mozambique Ocean and the development of the EAO is vital for constraining the evolution of the Neoproterozoic Earth system. ...
... Both South China and West Africa APWPs are close to, or overlap, the true polar wander paths. Our interpretation is that South China and West Africa were located near the downwelling girdle that surrounded the Rodinia supercontinent between 810-790 and 615-570 Ma, respectively 19 . In our reconstruction, the older (>750 Ma) subduction zone in the Mozambique Ocean is a relic subduction system related to the formation of the Rodinia. ...
... After 750-720 Ma, this relic subduction system ceased, and a new subduction system developed, which eventually led to the closure of Mozambique Ocean (Fig. 4b, c). The evolution of these subduction systems is consistent with the orthoversion supercontinent model 19,103 because they lie along a girdle that is~90°away from the center of Rodinia. ...
The serpentine orogenic belts that formed during the Neoproterozoic assembly of Gondwana resulted in geodynamic changes on the planet in advance of the Cambrian radiation. The details of Gondwana assembly associated with the closure of the Mozambique Ocean are enigmatic. We compile published geological and paleomagnetic data to argue that the Tarim block was associated with the Azania and Afif-Abas-Lhasa terranes and they were the locus of long-lived Andean-type subduction during the~900-650 Ma interval. Our model suggests a subduction system reorganization between 750-720 Ma, which resulted in two distinct phases of Mozambique ocean evolution. Between 870-750 Ma, a N-S oriented subduction system marks the locus of ocean crust consumption driven by the extension of the Mozambique Ocean. Beginning~720 Ma, a newly developed~E-W oriented subduction system began to consume the Mozambique Ocean and led to the assembly of eastern Gondwana. Our new reconstruction uses true polar wander to constrain the relative paleo-longitude of Tarim, South China and West Africa. In this scenario, the closure of the Mozambique Ocean and formation of Gondwana was orthogonal to the preceding super-continent Rodinia.
... We note that non-uniformitarian (non-GAD) magnetic fields such as alternating equatorial and polar dipoles have been proposed as an alternative explanation to TPW for anomalous APW such as the existence of both high and low paleolatitudes in the Ediacaran for Laurentia (Abrajevitch and Van der Voo, 2010). However, poles scattered in terms of declination, like Australia in the Ediacaran and Slave craton in the Orosirian (Mitchell et al., 2010b;Mitchell et al., 2012), can be explained in terms of TPW as continental rotations near the TPW axis, but cannot be explained by the proposed alternation between equatorial and polar dipoles. Neither can intermediate directions such as Ediacaran mid-latitude poles of Laurentia (McCausland et al., 2011) be explained by such a model, but are compatible with TPW. ...
True polar wander (TPW), or planetary reorientation, is the rotation of solid Earth (crust and mantle) about the liquid outer core in order to stabilize Earth’s rotation due to mass redistribution. Although TPW is well-documented on Earth presently with satellites and for multiple planets and moons in the Solar System, the prevalence of TPW in Earth history remains contentious. Despite a history of controversy, both the physical plausibility of TPW on Earth and an empirical basis for it are now undisputed. Lingering resistance to the old idea likely stems from the fact that, like plate tectonics, TPW may influence much of the Earth system, thus acknowledging its existence requires rethinking how many different datasets are interpreted. This review summarizes the development of TPW as a concept and provides a framework for future research that no longer regards TPW like a ghost process that may or may not exist, but as an integral part of the Earth system that can relate shallow and deep processes that are otherwise only mysteriously linked. Specifically, we focus on the temporal regularity of large TPW, and discuss its relationship with the supercontinent–megacontinent cycle based on previous studies. We suggest the assembly of mega-continents has a close linkage to large TPW. Meanwhile, supercontinent tenure and breakup have a close linkage to fast TPW. The effects of TPW on sea level changes, paleoclimate, biological diversity, and other facets of the Earth system are presented and require interdisciplinary tests in the future.
... Thus, each orogen may be viewed as having reached a certain stage of its evolution path in the Wilson Cycle. Moreover, active accretionary orogens will continue to evolve; for instance, the active accretionary orogenic systems around the margins of the Pacific Ocean, such as the North and South American Cordillera, may evolve or be reformed into collisional or even intracratonic orogens if the Pacific Ocean closes in the future (e.g., ref. 47 ). Based on this expected orogenic evolution, we can use the decrease in the juvenile crustal areal proportions to semi-quantitatively trace the orogenic stages from accretion to collision as each orogen progresses through the Wilson Cycle (Fig. 5). ...
The relationship between orogens and crustal growth is a fundamental issue in the Earth sciences. Here we present Nd isotope mapping results of felsic and intermediate igneous rocks from eight representative and well-studied Phanerozoic orogens. The results illustrate the distribution of isotopic domains that reflect the compositional architecture of the orogens. We calculated the areal proportion of juvenile crust and divided the orogens into five types: (i) highly juvenile (with >70% juvenile crust); (ii) moderately juvenile (70–50%; e.g., the Altaids with ~58% and the North American Cordillera with ~54%); (iii) mixed juvenile and reworked (50–30%; e.g., the Newfoundland Appalachians with ~40% and the Lachlan Orogen with ~31%); (iv) reworked (30–10%); (v) highly reworked (<10%; e.g., the Tethyan Tibet (~3%), Caledonides (~1%), Variscides (~1%), and the Qinling-Dabie Orogen (<1%)). This study presents an approach for quantitatively characterizing orogens based on compositional architecture through isotope mapping, and for investigating the relationships between orogenesis and continental growth.
... More generally, developments in the field of mantle dynamics, particularly in understanding the coupling between mantle convection patterns and plate tectonic activity, and the possibilities of deciphering the elusive palaeolongitude of both subduction and plume-related igneous complexes (e.g. Tan et al. 2002;Zhong et al. 2007;Li and Zhong 2009;Collins et al. 2011;Mitchell et al. 2012Mitchell et al. , 2021Torsvik and Cocks 2016;Li et al. 2019;Spencer et al. 2019), offer much promise in understanding how subduction-related systems evolve. Such advances in understanding are even more powerful when coupled with the increasingly more precise plate reconstructions (Domeier 2016;Merdith et al. 2017Merdith et al. , 2021Robert et al. 2018Robert et al. , 2021Wu et al. 2021Wu et al. , 2022. ...
The late Neoproterozoic-Cambrian interval is characterized by global-scale orogenesis, rapid continental growth, and profound changes in Earth systems. Orogenic activity involved continental collisions spanning more than 100 million years, culminating in Gondwana amalgamation. Avalonia is an example of arc magmatism and accretionary tectonics as subduction zones re-located to Gondwana's periphery in the aftermath of those collisions, and its evolution provides significant constraints for global reconstructions. Comprising late Neoproterozoic (ca. 650-570 Ma) arc-related magmatic and metasedimentary rocks, Avalonia is defined as a composite terrane by its latest Ediacaran-Ordovician overstep sequence; a distinctive, siliciclastic-dominated cover bearing “Acado-Baltic” fauna. This definition implies Neoproterozoic Avalonia may consist of several terranes, and so precise paleomagnetic or provenance determination in one locality need not apply to all. On the basis of detrital zircon and Nd isotopic data, Avalonia and other lithotectonically-related terranes such as Cadomia, have long been thought to have resided along the Amazonian-West African margin of Gondwana between ∼650-500 Ma, Avalonia connected to Amazonia, and Cadomia to West Africa. These interpretations have constrained Paleozoic reconstructions; many imply the departure of several peri-Gondwanan terranes led to the Early Paleozoic development of the Rheic Ocean whose subsequent demise in the late Paleozoic led to Pangea amalgamation. Since these ideas were proposed, several new lines of evidence have challenged the Amazonian affinity of Avalonia. First, there is evidence that some Avalonian terranes may have been “peri-Baltican” during the Neoproterozoic. Baltica was originally excluded as a potential source for Avalonia because, unlike Amazonia, arc-related Neoproterozoic rocks were not documented. However, subsequent recognition of Ediacaran arc-related sequences in the Timanides of northeastern Baltica invalidates this assumption. Second, detailed paleontological and lithostratigraphic studies have been interpreted to reflect an insular Avalonia, well removed from either Gondwana or Baltica during the Ediacaran and early Cambrian. Third, recent paleomagnetic data have raised the possibility of an ocean (Clymene Ocean) between Amazonia and West Africa in the late Neoproterozoic, thereby challenging conventional reconstructions that show the “peri-Gondwanan” terranes as a contiguous belt straddling the suture zone between these cratons. In this contribution, we critically re-evaluate the provenance of the so-called “peri-Gondwanan” terranes, the contiguity of the so-called “Avalonian-Cadomian” belt, and the validity of the various plate tectonic models based on the traditional interpretation of these terranes. In addition, we draw attention to critical uncertainties and the challenges that lie ahead.
... Here we follow a similar multidisciplinary approach as in Li et al. (2008b), including utilising the latest version of the Global Palaeomagnetic Database (GPMDB; Pisarevsky et al., 2022), and various other geological databases as discussed below. For global palaeolongitudinal constraints, we generally follow an extended-orthoversion assumption (Mitchell et al., 2012) as in , and discuss the merits and limitations of some alternative models in sections 2.3 and 6.3. ...
... Palaeomagnetism not only plays the most critical role in Precambrian plate reconstruction through providing palaeolatitudinal constraints and testing past continental connections through apparent polar wander path (APWP) comparisons (Evans and Pisarevsky, 2008), the documented (or hypothesized) true polar wander (TPW) events are also the essential evidence used for the preferred geodynamic model of supercontinent-superplume (LLSVP) coupling (Li et al., 2004;Li and Zhong, 2009) and the orthoversion model for palaeolongitudinal constraint (Mitchell et al., 2012) (see sections 2.3 and 6.3). ...
... How to assign palaeolongitude to supercontinents and palaeogeographic reconstructions in general is another challenge, as palaeomagnetism by itself is unable to provide absolute palaeolongitudinal information. Nonetheless, attempts have been made to control palaeolongitude indirectly through geodynamic assumptions (Mitchell et al., 2012;Torsvik et al., 2014). We will further discuss this topic in section 6.3. ...
Establishing how tectonic plates have moved since deep time is essential for understanding how Earth’s geodynamic system has evolved and operates, thus answering longstanding questions such as what “drives” plate tectonics. Such knowledge is a key component of Earth System science, and has implications for wide ranging fields from core-mantle-crust interaction and evolution, geotectonic phenomena such as mountain building and magmatic and basin histories, the episodic formation and preservation of Earth resources, to global sea-level changes, climatic evolution, atmospheric oxygenation, and even the evolution of life. In this paper, we take advantage of the rapidly improving database and knowledge about the Precambrian world, and the conceptual breakthroughs, both regarding the presence of a supercontinent cycle and possible dynamic coupling between the supercontinent cycle and mantle dynamics, in order to establish a full-plate global reconstruction from 540 Ma back to 2000 Ma. We utilise a variety of global geotectonic databases to constrain our reconstruction, and use palaeomagnetically recorded true polar wander events and global plume records to help evaluate competing geodynamic models and also provide new constraints on the absolute longitude of continents and supercontinents. After revising the configuration and life span of both supercontinents Nuna (1600—1300 Ma) and Rodinia (900—720 Ma), we present a 2000—540 Ma animation, starting from the rapid assembly of large cratons and supercratons (or megacontinents) between 2000 Ma and 1800 Ma. This occurred after a billion years of dominance by small cratons, and kick-started the ensuing Nuna and Rodinia supercontinent cycles and the emergence of stable, hemisphere-scale (long-wavelength) degree-1/degree-2 mantle structures. We further use the geodynamicly-defined type-1 and type-2 inertia interchange true polar wander (IITPW) events, which likely occurred during Nuna (type-1) and Rodinia (type-2) times as shown by the palaeomagnetic record, to argue that Nuna assembled at about the same longitude as the latest supercontinent Pangaea (320—170 Ma), whereas Rodinia formed through introversion assembly over the legacy Nuna subduction girdle either ca. 90◦ to the west (our slightly preferred model) or to the east before the migrated subduction girdle surrounding it generated its own degree-2 mantle structure by ca. 780 Ma. Our interpretation is broadly consistent with the global LIP record. Using TPW and LIP observations and geodynamic model predictions, we further argue that the Phanerozoic supercontinent Pangaea assembled through extroversion on a legacy Rodinia subduction girdle with a geographic centre at around 0◦E longitude before the formation of its own degree-2 mantle structure by ca. 250 Ma, the legacy of which is still present in present-day mantle.
(the paper is of OPEN ACCESS at http://dx.doi.org/10.1016/j.earscirev.2023.104336)
