Basal mantle structure regenerated through supercontinents

Domain: earth_science
Published: 2025-11-03
Editorial outcome: minor_revision

Abstract
The African large low shear wave-velocity province (LLSVP) advected plumes manifest as large igneous provinces (LIPs) during Pangea breakup. The existence of such basal mantle structures during earlier supercontinents is unknown. Here we analyze samples from China and Brazil to demonstrate with literature data a series of seven LIPs of supercontinent Rodinia from 940–720 million years ago. Multi-proxy reconstruction results in a coherent ring of LIPs comparable with the size of Rodinia that resembles the product of an ancient LLSVP whose edges advected LIP-producing plumes. Oceanic lithosphere recycling following supercontinental assembly is evident in Nd isotopes as evolving LIP-sources. There is a same secular variational pattern of LIP sources with a replenished depleted component advected by plumes as well as a similar manner yet contrasting paleogeographic configurations corresponding to supercontinental breakup between Rodinian and Pangean LLSVPs. This evolving pattern of LLSVPs suggests their partial regeneration (replenishment and migration) between supercontinents.

Introduction
Large low shear wave velocity provinces (LLSVPs) in the lowermost mantle imaged seismically 1–3 represent the largest geophysical/geological structures on the planet. Although imaged only at the present-day, LLSVPs exhibit correlations with geological data that suggest the basal mantle structures could be quite ancient. The configuration of such historical basal mantle structures reveals a close but enigmatic relationship between LLSVPs and supercontinents 4. As such, LLSVPs have the potential for informing the geodynamic–tectonic coupling of historical supercontinent cycles, as well as the prediction of a future supercontinent 5,6. At present, Earth has two antipodal and equatorial LLSVPs that reflect the dominance of degree-2 mantle convection 2,3.

LIPs occurring in the Pacific Ocean including ocean plateaus are well-documented to correlate with the Pacific LLSVP with significant interaction between plumes and mid-ocean ridges in pulses separated by ~10–20 million years (Myr, ref. 7). The present African (hereafter ‘Pangean’ to name the historic one during the Pangea tenure) LLSVP is thought to have been responsible for the breakup of the Pangea supercontinent, which lasted for 200 Myr accompanied by six major large igneous provinces (LIPs)/plumes 8–12 (Fig. 1). It has been revealed that all these LIPs systematically occurred within or along the edges (within ~10˚; ref. 13.) of the Pangean LLSVP and have thus arguably been advected by it 10,14 (Fig. 1). It therefore begs the question whether Pangea’s predecessor also had a LLSVP beneath it, and reconstructing the LIPs that might have emanated from it is an obvious test of its existence. In addition, beyond a certain age, which is debated, the formation 15–17 and the fixity 18,19 or mobility 20–22 of the present LLSVP is unknown, yet critical for understanding geodynamic–tectonic coupling.

In this study, building of the empirical and theoretical correspondences among a supercontinent, its LIPs, and its underlying LLSVP, we attempt to identify a hypothetical LLSVP underlying Neoproterozoic supercontinent Rodinia using its LIPs and to decipher its formation by comparing it with that of the Pangea (Fig. 1). Datasets of the geochronology and geochemistry of the global Rodinian LIPs—in total, 22 elements (Fig. 2)—are compiled, among them the ca. 920 Ma and ca. 820 Ma LIPs are updated with analyzed data (Methods; Supplementary Data 1–4; literature data from Supplementary References). The geometries of all these LIPs are reconstructed based on a synthesis configuration of Rodinia 23,24 in order to assess their possible corresponding basal mantle structure during the evolution of the Neoproterozoic supercontinent; while the secular variations of geochemical proxies of the Rodinian LIPs, as well as their comparison with the Pangean LIPs and LIPs during the supercontinental assembly and tenure, are analyzed to constrain the evolution of this basal mantle structure (Methods).

Results
Chemical evolution of global 940–720 Ma (Rodinian) LIPs

Vestiges of each Rodinian LIP are internally consistent in chemistry and all the LIPs have an affinity of continental flood basalts, referring a plume-origin (Methods). Comparing the seven Rodinian LIPs, there are both notable similarities and systematic changes over time. The εNdt values exhibit dominantly chondritic-like values, though there is an increase of diversified features with younging direction (Fig. 3). This commonality may indicate a similar dominant source for the seven LIPs, one which was extracted from primitive mantle as chondrite-like (primordial) source(s), and the cumulative decay of Sm through time hardly changed their εNdt values. However, they also show a transition from initially narrow values that evolve over time into a fanning isotopic array toward both more enriched and depleted εNdt values (Fig. 3). This observation may suggest an increasing contribution of depleted (mantle) source(s) on one hand, and a simultaneous increasing contribution of enriched source (Nd TDM > 1700 Ma) on the other. For instance, among the seven LIPs, the ca. 720 Ma LIP shows the widest span of εNd values (Fig. 3), which may indicate the largest contributions of ancient lithosphere while simultaneously also the largest contribution of depleted mantle, both in addition to the primordial source. There are systematic changes of chemical proxies in the LIP compositions over time: The decreasing of Gd/Yb n while the elevated Mg-numbers, Ni-contents, and Nb/Ta ratios over time might indicate increasing influences of depleted source with depleted compatible elements 25 in the primordial magmas (Fig. 3) (Methods). In summary, the Rodinian LIPs exhibit an increasing geochemical diversity with increasing contributions from both enriched and depleted sources over time, a compositional pattern similar to that of the Pangean (Fig. 3).

Reconstruction of Rodinian LIPs

Seven Rodinian LIP episodes are classified, i.e., ca. 940 Ma Göteborg-Baengnyeong, ca. 920 Ma Dashigou–Gangila, ca. 890 Ma Iguerda–Sariwon, ca. 820 Ma Willouran-Qianlishan, ca. 780 Ma Gunbarrel, and ca. 720 Ma Franklin (Fig. 2), which are consistent with the peaks in the probability histogram of all available ages of the global LIP vestiges (Fig. 1). It is well-known that the pinpoint of a giant dike swarm of a LIP estimates its plume center 26,27. Here, all the coeval units of a potential LIP are correlated to estimate its magma center close to breakup margins based on the paleogeographic reconstruction in the framework of the Rodinia supercontinent. Two prevailing reconstructions of Rodinia by Evans 23 (Fig. 4a) and Li, et al. 24 (Fig. 4b) are applied. Both options successfully reconstruct most LIPs, but do not support the correlation of all the others as an intact LIP at each stage. To construct as many associated units to a same LIP center as possible, a few cratons including North China 28 and Tarim 29 during 940–760 Ma and South China 24,30 during 820–720 Ma are relocated based on alternative possibilities based on the configuration of Evans 23 (Fig. 4c), which constructs all vestiges of 940–720 Ma LIPs from different blocks into intact LIPs of each time, compatible with the available paleomagnetic data. The three models yield slightly different spatial distributions of plume centers and LIPs; yet they all show three major break-up stages, i.e., São Francisco–Congo and West Africa during 940–890 Ma, Indian and Australia-East Antarctic during 820–760 Ma, and finally Siberia at ca. 720 Ma (Fig. 4d–f).

Methods
Geochronologic and geochemical analyses

Fresh samples were obtained from the ca. 920 Ma (Dashigou and Bahia dike swarms) and ca. 820 Ma (Luanchuan sill complex) LIP vestiges in the North China and São Francisco-Congo cratons. The information of the samples are provided (Fig. 2; Supplementary Data 1; Supplementary Figs. 1 and 2).

Bulk whole-rock elements and Nd–Sr isotopes of some representative samples are analyzed in the Institute of Geology and Geophysics, Chinese Academy of Sciences (IGGCAS, Beijing). Major element determinations are performed by X-ray fluorescence and the precisions are better than 0.2 wt% in the analyzable ranges. Trace element analyses are determined using inductively coupled plasma-mass spectrometry (ICP-MS) and the relative standard deviation was better than 5% above the detective limit. Sr–Nd isotope determination is made by ICP-MS, and the procedure backgrounds for Sr–Nd isotope analyses were better than 50 pg, and the external precision (2σ) of 147Sm/144Nd ratios was better than 0.5%. All the generated data are compiled together with global datasets (Supplementary Data 2 and 3) and plotted together (Supplementary Figs. 3 and 4).

Baddeleyite (ZrO 2 ) grains are liberated from coarse samples. The minerals are then mounted in an epoxy resin and their U–Pb isotopic ratios are analyzed using a multi-collector CAMECA 1280 IMS facility in the IGGCAS. The diameter of the ion beam for analyses is ~20 μm. During data processing, an average of present-day crustal composition is used for common Pb correction, and the weighted means are given at 2σ (Supplementary Data 4). Analytical procedures and data processing follow those described in ref. 59.

Application of geochemical proxies (Mg number, Ni content, Gd/Yb n , 87Sr/86Srt, εNdt, and Nd T DM age)

Here a few geochemical proxies of whole-rock compositions are applied. Among them, Mg number is calculated as Mg/(Mg+Fe) in molecular; while Gd/Yb n is Gd/Yb ratio of a rock normalized to chondrite. Due to the different compatibility of elements between melts and minerals (mantle source) 60,61, Mg numbers, Ni contents and Nb/Ta ratios are relatively higher in melts with higher degrees of melting from a same source, and melts from relatively more depleted sources 25,62 may show relatively higher of these values; while Gd/Yb n values are on the contrary. In addition, crustal rocks/melts have much lower Mg numbers, Ni contents and Nb/Ta ratios but distinct higher Gd/Yb n values 63. It should be also mentioned that these values/ratios can be decreased in the magma when a fractionating phase is compatible with the proxies.

87Sr/86Srt, εNdt and Nd T DM ages are calculated (Supplementary Data 3):

87Sr/86Srt = 87Sr/86Sr - 87Rb/86Sr × (eλtage - 1)

Where λ = 1.42 × 10-11 Myr-1.

εNdt = 10000 × [ (143Nd/144Nd sample, measured - (147Sm/144Nd sample, measured) × (eλtage, Ma - 1)) / (143Nd/144Nd CHUR, 0 - (147Sm/144Nd CHUR, 0 × (eλtage, Ma - 1)) - 1 ]

Nd T DM age = (1/λ) × ln( (143Nd/144Nd sample - 143Nd/144Nd DM) / (147Sm/144Nd sample - 147Sm/144Nd DM) + 1 )

Where 143Nd/144Nd CHUR, 0 = 0.512638, 147Sm/144Nd CHUR, 0 = 0.1967; 143Nd/144Nd DM = 0.51315; 147Sm/144Nd DM = 0.2137, and λ = 6.54 × 10-12 Myr-1.

Here 87Sr/86Srt refers to 87Sr/86Sr of an igneous rock at the time of its crystallization while εNdt 64 refers to 143Nd/144Nd at the time of crystallization normalized to that of chondrite. Both proxies indicate the nature of source of an igneous rock which it crystalizes. In a close system, the 87Sr/86Sr (143Nd/144Nd) of a rock/source region increases due to the decay of 87Rb to 87Sr (147Sm to 143Nd); and the higher the Rb/Sr (Sm/Nd), the more prominent the increase. In addition, if 147Sm/144Nd is lower (higher) than a chondrite value (0.1976), εNdt decrease (increase) (Fig. 3). Nd T DM age 62 refers to the age assuming an igneous rock derived from the secular depleted mantle after the historical derivation of lithosphere.

Discrimination of ancient large igneous provinces (LIPs) with plume origin and reconstruction of their plume centers

LIPs comprise large volumes of mafic rocks, represented by flood basalts; however, many of them were eroded, leaving vestiges of mainly their plumbing system represented by the dike swarms, and dispersed during continental breakup 65,66. Consequently, LIP elements with similar high-precision ages (e.g., baddeleyite U-Pb ages) were possibly dispersed from a historically same LIP, if they can be tested by associated compositions and paleogeographic reconstructions (e.g., close to each other enough in a paleogeographic model). LIPs are characterized by igneous pulse of short duration (~1–5 Myr) with a maximum lifespan of ~50 Myr 67. The associated compositions are represented by consistent patterns in the chondrite- and primitive mantle-normalized trace element spidergrams (Supplementary Fig. 3), as well as closely distributed Sr-Nd isotopes for samples of the same swarm (Supplementary Fig. 4a). All the global ca. 940–720 Ma LIP elements are collected (Supplementary Data 1), which are mostly summarized in www.largeigneousprovince.org and documented previously 68–72 but here in the ca. 920 Ma and ca. 820 Ma LIP elements are updated to give better constraints on the global paleogeographic reconstruction at these two very periods. Here we arbitrary take 20 Myr as a kind of threshold as all the age data of LIP vestiges of 940–720 Ma LIP elements show different peaks with widths of within 20 Ma (Fig. 1) and as many of these ages have errors range from 1 to 10 Ma irrespectively of systematic errors induced by different labs (Supplementary Data 1); and thus this age threshold is rather an age uncertainty than durations of events. Based on the compiled datasets and data reported here, totally seven LIPs are defined: i.e., ca. 940 Ma Göteborg–Baengnyoeng LIP (with dismembered elements in Baltic and North China) 73–75, the ca. 920 Ma Dashigou–Gangila LIP (with elements in North China, São Francisco–Congo, and West Africa) 72,76,77, the ca. 890 Ma Iguerda–Taïfast LIP (with elements in North China, West Africa, and Tarim) 75,77–80, the ca. 820 Ma Willouran–Guibei LIP (with elements in South Australia, South China, Tarim, and North China) 81–84, the ca. 780 Ma Gunbarrel–Yanbian LIP (with elements in Laurentia, South Australia, South China, and West Australia) 68–70,85–87, ca. 760 Ma Mundine Well LIP (with elements in South Australia, Laurentia, and India) 68–70,85–87, and the ca. 720 Ma Franklin LIP (with elements in Laurentia, Greenland, Siberia, and South China) 71,88–90 (Fig. 2). Each generation of LIP vestiges shows consistent trace element patterns, and most of them show similar trace element patterns akin to ocean island basalt and global LIPs/continental flood basalt, or around two patterns (Supplementary Fig. 3). Such an affinity is consistent with those of the products of mantle plumes 91. Their Sr-Nd isotopes plot mostly along the mantle array and close to the chondrite line, varying from prevalent mantle and enriched mantle; while the TiO 2 /Yb versus Th/Nb diagram 92 shows a feature of plume array with varied degrees of lithospheric input (Supplementary Fig. 4a, b). This agrees with the result of broad studies that the Rodinia has been invoked in the advection of multiple plumes during 940–720 Ma, leading to the diachronous breakup of the supercontinent 68,72–80.

Giant radiate dike swarms are typical magma plumbing systems of LIPs produced by plumes 26,27; consequently, coeval fossil units of a potential LIP can be correlated to estimate its magma center along the breakup margins, as well as the pinpoint of the dike swarm. Due to a complicate situation of preservation, as well as post-emplacement breakup, the original radiating dike swarm may present as dismembered fossil units. The plume centers of the above seven LIPs are reconstructed by join vestiges of a same LIP as many as possible, and geographically neighboring as close as possible, using different reconstructions of global continents (Fig. 4c). The two key LIPs (920 Ma and 820 Ma) with substantial updates and definition, are specified below.

Reconstruction of the 920 Ma LIP: Vestiges of the ca. 920 Ma LIP have been identified on two cratons, including the Dashigou dike swarm 93 and associated sill complexes near the magmatic center (rift) 94 in the North China craton, and the Bahia-Gangila-Mayumbian dike swarm and the associated sill complexes, volcanics, and plutons in the São Francisco craton 72 (Fig. 2; Supplementary Figs. 1 and 2). The ca. 920 Ma dikes of both cratons are generally wide (10–50 m) and gabbroic to doleritic 72,93; and the sills are generally thick (100–150 m) and show highly differentiated layers (including syenitic and high-Fe-Ti gabbroic layers) 94. Matching trace element patterns (Supplementary Fig. 3) of the two swarms specifically represented by the two dikes support the hypothesis that these vestiges were part of the same, since dismembered LIP 72,93. Here one baddeleyite sample from a ~50-m-wide, 315˚-trending doleritic dike from the Dashigou swarm of North China give a 207Pb/206Pb age of 918 ± 4 Ma (MSWD = 1.3; n = 14), which is within error the same with the other from a ~40-m-wide 285˚-trending doleritic dike from the Bahia dike swarm of São Francisco (207Pb/206Pb age, 914 ± 8 Ma, MSWD = 0.6; n = 8) (Supplementary Fig. 2). The consistence with reported data (Supplementary Data 1) negates intra-laboratory systematic error and verifies the contemporaneous of the two swarms. It has been proposed the magma center of the Dashigou units was located at the present southeast margin of North China in the Xuhuai rift 94, while that of the Bahia–Gangila–Mayumbian units was located at the present southeast margin of São Francisco in the Macaúbas basin 72 (Supplementary Fig. 1). To reconstruct these units as a contiguous LIP, the magma/rift centers of the two associated cratonic margins should have been conjugate margins and be as closely positioned as possible. The εNdt values of the rocks vary from −2.0 to +3.0 and 87Sr/86Srt vary between 0.702–0.710, and are close to the prevalent mantle (PREMA) (Supplementary Fig. 4a). They have bimodal compositions 94, enriched light rare earth elements, and minor depletion in high-field strength elements compared with the neighboring large-ion lithophile elements, which match that of continental flood basalt and is close to those of oceanic island basalt (Supplementary Fig. 3) and show a mixing trend between plume and lithosphere (Fig. 3) 92.

Reconstruction of the 820 Ma LIP: Vestiges of the ca. 820 Ma LIP have been reported from Gawler (South Australia) as represented by the Willouran (Gairdner) dike swarm and volcanic province 81, South China as represented by the Guibei volcanic-dominated igneous province (with minor dikes) 81,82, and Tarim as represented by the Aksu dike swarm 84. There are also contemporaneous components in North China, including the Qianlishan dike swarm 95, the Jinchuan ultramafic-mafic intrusions (hosting a world-class Ni-Cu deposit) 96, and the bimodal Langshan volcanics 97 along the western margin, and the Luanchuan bimodal sill complex 98 along the southern margin (Fig. 2; Supplementary Figs. 1 and 2). The dikes of this event exhibit variable widths (several to tens of meters) and are generally doleritic, with some varieties such as picrite, gabbro, and syenite 81,82,95. These igneous units along the southern and western margins of North China show similar features, e.g., bimodal compositions (mafic/gabbro and felsic/granosyenite) and similar geochemical patterns and Nd-Sr isotopes (Supplementary Figs. 3 and 4a). They are proposed as vestiges of the 820 Ma LIP. Except some volcanics with scattered lithophile-affinitive elements (e.g., the Bikou volcanics in South China), most rocks in North China, Tarim, South China, and South Australia are typically rich in Ba (up to 5000 ppm) (Supplementary Data 2). Their variation from depleted to enriched in Sr and Eu, the largest among the seven LIPs (Supplementary Fig. 3), is consistent with their large lithological variation (from picrite to syenogranite), indicating considerable fractionation, which is further supported by the largely varied contents of compatible elements, such as Ni (Fig. 3). Such similar features among rocks from four different cratons also supports the hypothesis that they are parts of a dismembered LIP. These correlative vestiges of the same LIP indicate magma centers at the present western margins of North China and Tarim and the southeastern and southwestern margins of South Australia and South China, respectively (Fig. 4). The εNdt values of the rocks vary from −7 to +4.5 and 87Sr/86Srt vary between 0.702–0.708: They are close to ocean island basalt, but also showing a transitional feature of melts from prevalent mantle and enriched mantle (Supplementary Fig. 4a). They have bimodal compositions 95, enriched light rare earth elements, and minor depletion in high-field strength elements compared with the neighboring large-ion lithophile elements, which match that of continental flood basalt and ocean island basalt (Supplementary Fig. 3) and show a mixing trend between plume and lithosphere 92.

Peer review rounds
[{"round": 1, "reviewer_comments": {"reviewer_1": "This paper investigates the evolution of large low shear wave velocity provinces (LLSVPs) and their role in supercontinent cycles. The authors identify seven large igneous provinces (LIPs) associated with the Rodinian supercontinent (940–720 Ma), forming a coherent ring used to infer the shape of the LLSVP at that time. Chemical proxies, such as Nd isotopes, indicate that recycled oceanic crust contributed to LIP formation during supercontinent breakup, suggesting that oceanic crust might be incorporated into LLSVPs. The study highlights the interplay between mantle dynamics and supercontinental evolution.\n\nThe authors’ combined use of geochemistry and reconstruction of continents and LIPs to study LLSVPs offers a novel perspective, especially given that most previous studies have relied on numerical modeling. I recommend the manuscript for publication after addressing some modifications and clarifications.\n\nMain Comments:\nThe term \"regeneration\" is unclear. Does it imply that the LLSVP was destroyed and then regenerated, or that it was simply modified through the addition of oceanic crust? From Figure 4 and the related text, I infer that the regeneration refers only to the upper layer of the LLSVP, not the bottom layer.\nThis paper refers to the present-day African LLSVP as the Pangean LLSVP, but Pangea broke up more than 100 Ma ago. How are the Pangean and Rodinian LLSVPs defined, and when did the transition between them occur?\nRegarding the paleogeographic reconstruction, does it align with paleomagnetic data, or are the modifications directly adopted from other studies? Latitude should remain unchanged during these modifications.\nPrevious studies suggest that both subduction (e.g., Merdith et al., 2021, ESR) and plume activities (Figure 1, and also Condie et al., 2021, Gondwana Research) are largely continuous processes without significant time gaps since Rodinia. Slabs may have continuously sunk into the deep mantle, modifying LLSVPs, although subduction rates (and locations) likely changed during supercontinent assembly and breakup stages. This study primarily focuses on LIPs from supercontinent breakup stages. Could you explain why LIPs from assembly stages are considered less significant?\nIn the last paragraph, the authors state, “the shallow domains of the Pacific LLSVPs were not able to be regenerated due to the absence of subducting oceanic crust into the region.” This statement is not entirely accurate. Numerical models show that, while subduction mostly dips toward continents in the upper mantle, some slabs flow toward the Pacific LLSVP in the deep mantle. It is probably true that few slabs descend directly above the Pacific LLSVP to sink onto its top surface.\n\nMinor:\nAbstract: The last sentence is complex and could be restructured for better clarity.\nFigure 1: The figure shows plate speed, but it seems to only represent the speed of major continents. Since there is little Jurassic and older oceanic crust preserved. If you look at the Fig.7 of Muller et al. 2022, the global plate speed (both continent and ocean) in the Cretaceous is pretty high.\nLine 75, “while its LLSVPs”, does this mean Pangean LLSVPs?\nLine 101, This is Figure 2, not 3. The breakup of Rodinia around ~900 Ma seems somewhat early. In addition, in the top-left corner of the figure, the phrase “adding of reclyled … during Rodinia assembly” is paired with two arrows, and the right arrow points to Pangea (not Rodinia) assembly.\nLine 149, 940-890 Ma?\nLine 177, the statement, \"the fact that Pangea and Rodinia are supercontinents of broadly similar hemispheric-scale size,\" may not be accurate, particularly for Rodinia. Reconstructions of Rodinia are models and remain subject to significant uncertainty.\nLine 224: not all mantle material extracted from LLSVPs becomes LIPs; some material is mixed with the ambient mantle instead.\nLines 236–239, how the ascent rate of plumes is linked to the timing of increases in LLSVP influx and outflux?\nLine 257, the term “these drifted cratons” is unclear", "reviewer_2": "Review for ‘Basal mantle structure regenerated through supercontinents’\nSummary of the manuscript:\nThe manuscript by Peng et al. presents an investigation into the long-term dynamics of LLSVPs through the comparison between basal mantle structures beneath the Pangean and Rodinian supercontinents. New geochemical analysis from samples at 2 LIP sites are presented along with previously published analysis to allow comparison of geochemical properties of LIPs spanning the breakup of Rodinia (and Pangea). The results suggest that the palaeogeography of both LLSVPs can be recreated from the location of LIPs, and that they follow similar geochemical evolutions. They propose that these similarities require a regeneration of LLSVPs between supercontinents, driven by subduction dynamics.\nThis work represents a significant contribution to the ongoing discussions about the relationship between LLSVPs, LIPs and continental break-up. The model presented, along with the accompanying geochemical evidence, will be of interest to the community.\nA comment on expertise. The method of geochemical analysis lies outside of our area of expertise; however, we are very comfortable commenting on the manuscript which principally focusses on understanding the evolution of LLSVPs and from the perspective of LIP driven super-continental breakup.\nNote that the line numbers in the PDF and Word document are not the same – the line numbers below refer to those in the PDF file.\nPaper presents new geochemical data but this is not mentioned in the abstract – this is an important aspect of the work.\nLine 67: Figure 1 subfigures not labelled (e.g. a, b, c) so the figure caption is hard to follow. Axis label implies number of orogens but the caption says you are plotting orogen lengths? Are secondary y-axes same for number of LIPs and probability?\nLines 69-70: Is this really an anticorrelation? Especially dubious for the orogen length. A correlation coefficient would be helpful if possible.\nFigure 2: This is incorrectly labelled as Figure 3. The inset plot of Mg#, Ni, Nb/Ta, Gd/Yb need better separation from the plot of εNd, it is confusing to read at first. Perhaps the shading around the εNd plots could be darker too for emphasis.\nFigure 3. The plots in the right-hand column need to have sub-plot numbers. On the reconstructions of the LIP locations in the synthesis model. The locations plotted in 3c (bottom left) assume that the plumes move with the plate motions as Rodinia undergoes breakup. Is this an assumption that you make? If we understand correctly, the locations plotted here are the locations of the LIPs Would a better estimate for the LLSVP boundaires be from plotting the absolute eruption locations of the LIPs rather than their location relative to the cratons while Rodinia was still intact? This would certainly lead to a different shape of your LLSVP.\nLines 249-251: Needs clarifying. Need to quantify the volume of the LIPs if you want to make this comparison. Also, models do not suggest that all subducted oceanic crust would be incorporated into LLVPs and estimating the volume of melt produced by LIPS is different to estimating the amount of material advected away from LLVPs. You can highlight the similar trends but cannot compare the mass fluxes.\nThe ‘regeneration model’ should be explained a little bit in more detail in the main text – not just consigned to the figure caption of Fig 4. There are some details missing such as how can the model account for material which is subducted whilst the supercontinent is extant?\nGenerally, there are quite a few sentences which have quite difficult wording and are often too long so that the point of the sentence is unclear or obscured. Some of these have been noted below.\nMinor comments:\nLines 19-20 : This wording could implies that the basal mantle structures come directly from the supercontinents - I don't think that is what you mean.\nLines 29-33: This sentence is very weighty and so obscures the point you are trying to make.\nLine 36: Would argue that they are geophysical structures.\nLine 72: Should specify that it is data for the seven Rodinian LIPs which is presented.\nLine 74– 76: This makes it sound like you have a seismic velocity model for when Pangea was extant. Are you assuming that the LLSVPs are fixed?\nLine 79: what do you mean by ‘internally consistent in chemistry’. Does not seem to agree with the changes in chemistry with time that you observe.\nLines 82-83: ‘increase of diversified features’ with increasing age.\nLines 83-85: This sentence is slightly unclear. We think that you are saying that the Rodinian LIPs have a common source which is chondritic?\nLines 93-95: This sentence needs references to support the point.\nLine 113-115: This sentence needs a reference.\nLine 155: ‘Totally seven Rodinian LIPs’ is not very clear\nLine 156: ‘Coincide with a trench in both orogen lengths and plate speeds’, can see a trough in orogen length but not so clear for the plate speeds.\nLine 182: Fig 3c – is that the right subfigure?\nLine 235: ‘... roughly similar peaks’. Peaks in what?\nLines 244-246: This is unclear. Are you saying that the primordial source is not significantly altered through time and is not enough alone to explain the trends?\nLine 264 266: See Mulyukova et al., 2015 (JGR Solid Earth) and Panton et al., 2025 (Scientific Reports) for geodynamic which are argued to support ‘regeneration’ (or replenishment).\nLines 266 – 271. The sentence is quite clunky, needs splitting up and rewriting. Also reference 46 is a simulation which does not explicitly subduct oceanic crust, rather it is initialised with a layer of ‘ocenaic crust’ above a ‘primordial’ layer – so I think these simulations are not appropriate for the point you are trying to make.\nBest of luck with the submission, James Panton and Abigail Plimmer.", "reviewer_3": "I co-reviewed this manuscript with one of the reviewers who provided the listed reports. This is part of the Nature Communications initiative to facilitate training in peer review and to provide appropriate recognition for Early Career Researchers who co-review manuscripts.", "reviewer_4": "Dear authors,\nThe content is interesting and well written, figure are well presented but could be performed. The English can also be polished a little. The author should clearly define what is “regeneration”. Geological and/or geochemical consequences expected? The paper considers that Gondwana is not a supercontinent. However, it is clear from figure 1 that there are a lot of orogens formed at 600 Ma. The author needs to discuss this point in details. Why LIPS and orogens are formed at the same time at 600 Ma if the break ups of Rodinia terminate at 700 Ma?\nSecondly, If the breakup occurs at 940-720 Ma then what happens to the LIPS formed at 600 Ma that are usually considered as protracted breakup of Rodinia. Especially, if there is a terminal plume formed before 600 Ma (i.e., 700 Ma). In this new model, how to interpret the 600 Ma LIPS ? A reappraisal of the 600 Ma LIPS should be done and mentioned.\nThe author have to mention the paper which also suggest that the decrease of Hf isotopes occurs during break up of supercontinents. (i.e., Bahlburg et al., 2025). Thus, it is not the first paper to propose reworking during breakup. Although Bahlburg only proposes decrease of Hf isotopes during breakup, the submitted manuscript proposes widening of the Hf array and increase reworking towards younger time which is new. Please mention that paper in your manuscript.\nThe author should say what it means by regeneration, by giving a clear definition of the process and the geological consequence of regeneration of the mantle structure LLSVPs.\nFigures:\nFigure 2 and 3 have the same number which is 3, it should be corrected because it is difficult to review the paper.\nFigure 1:\nMy first question is about the fact that the peak of orogens occur at 600 Ma. How do you explain this in the framework of having also LIPs formed at 600 Ma, although its not many. In addition, Condie et al. 2021 have a different dataset for the LIPS province with data almost continuous during the Earth evolution. Why your dataset varies? How to interpret the dataset from Condie et al. 2021 and the one used in your study?\nFigure 2:\nI agree with this graphic, but why did you not plot the LIPs at 600 Ma as well? Maybe it could show no trends at Gondwana, supporting you interpretation of Rodinia through Pangea. It is a possibility to support your model of Gondwana not being a supercontinent and part of the assembly of Pangea.\nI did not find a reference for “Terminal Plume” in the literature for Pangea. Ethiopia has 3 vertical bar? Please name each bar in the graphic as you did from 900 to 700 Ma. You should give a proper reference of this “plume” for Pangea. If terminal plume is a prediction of the composition of the plume at 0 Ga and not a geological record should be stated clearly in the manuscript? If I missed the reference, kindly show us the reference.\nFigure 3:\nAlso explain clearly what is the underlying hypothesis to consider a synthesis model and not only one of the two previous models of Li et al. 2023, or Evans et al. 2021. A plume is circular, therefore LIPS should be centred on the plume head ?\nText :\nLine 167: This phrase does not read well. Could you change it?\nLine 219: change two more basics, which reads strangely.\nLine 228: “However, it needs to be mentioned that the influx of oceanic crust should be larger during breakup than assembly stages of supercontinents cycles”.\nI strongly advise to add these two references to support your claim: Broussolle, 2022 and Gardiner et al. 2016. Indeed, these two references support that reworking occurs during assembly of supercontinents and Gardiner et al. 2016 shows that arc setting forms juvenile signatures.\nLine 239: explain timely “refreshed” here\nLine 245: negatable should be changed too\nLine 247: the sentence does not reads well, could you change it please.\nLine 299 The shallow domain is generating during the breakup stages.\nHere generating should be modified for generated ?\nReferences :\nBroussolle, A. (2022). Mathematical modelling reveals potential acceleration of the supercontinent cycle. Scientific Reports, 12(1), 17391.\nBahlburg, H., Kemp, A. I., Fanning, C. M., & Martin, L. (2025). The Hf and O isotope record of long-lasting accretionary orogens: The example of the Proterozoic and Paleozoic-Triassic central South America. Earth-Science Reviews, 105068.\nCondie, K. C., Pisarevsky, S. A., & Puetz, S. J. (2021). LIPs, orogens and supercontinents: The ongoing saga. Gondwana Research, 96, 105-121.\nGardiner, N. J., Kirkland, C. L., & Van Kranendonk, M. J. (2016). The juvenile hafnium isotope signal as a record of supercontinent cycles. Scientific reports, 6(1), 38503.\nTable\nSupplementary material 4 take out the comments with “outlier”.\nBest regards,\nArnaud Broussolle"}, "author_response": "Dr. Peng Peng, Professor (pengpengwj@mail.iggcas.ac.cn)\nInstitute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China\nDear Reviewers,\nPlease find enclosed our revised manuscript entitled ‘Basal mantle structure regenerated through\nsupercontinents’(NCOMMS‐24‐68926A) resubmitted to Nature Communications. We have revised\nbased on reports from 4 reviewers. Point‐by‐point replies are below, and major revisions include:\n The ‘regeneration’ of LLSVPs is defined. It refers to material being ‘replenished’ through\nsupercontinental cycles, as well as the migration of the basal mantle structures (mainly their\nshallow domains) to couple the mantle with the supercontinental lid during assembly. Lines 314‐\n318. [Reviewers #1#2#3#4]\n The synthetic model is compatible with paleomagnetic data available. The revision further\nemphasizes that the synthetic model is revised from ref1, with only a few less‐constrained cratons\n(e.g., NCC, SCC, Tarim) relocated based on the reconstructions of the same LIPs and the\nalternative connection models of these cratons with the core members of the Rodinia. This\nrelocations are compatible with the paleomagnetic data available. Lines 147‐151. [Reviewers #1]\n Subfigures of Figures 1 and 3d are numbered. [Reviewer #1#2#3]\n Reconstruction of the Rodinian LLSVP based on ‘restored’ vs. ‘real‐time’ LIP centers is illustrated.\nRodinian LLSVP reconstructed by the ‘real‐time’/’contemporary’ LIP centers at each age during\nRodinia breakup is added in Figure 3f to compare with the ‘restored’ LIP centers in the intact\nRodinian reconstructions. It yields a slightly different shape. Two reasons to use the ‘restored’ LIP\ncenters deduced from the intact Rodinian reconstruction: 1) This is an empirically‐based LLSVP\nreconstruction method learnt from the Pangean LLSVP2,3 (Fig. 1a): and 2) our ‘regeneration’\nmodel indicates that the basal mantle structure was formed and less dynamic since\nsupercontinent assembly, and only the plumes (and thus LIP centers) may be trail due to coupling\nwith overriding plate motion (e.g., the Hawaiian plume4). Lines 330‐342. [Reviewer #2#3]\n The significance of LIPs during assembly is clarified. We have plotted in Figure 2 the LIPs during\nthe assembly of supercontinents especially those associated with the forming of Gondwana. They\nshow a diversified feature which is significantly different from the pattern of the breakup LIPs.\nThese LIPs either show a continuous phase of a plume since its initial breakup (e.g., Central\nIapetus5) or lithosphere (e.g., Volyn6), or subduction related (e.g., Emeishan7). It has been\nproposed by multiple models that the Rodinia supercontinent has a protracted breakup to as late\nlate as ca. 600 Ma (refs.1,8); however, the LIPs during this period shows features of primitive sources\n(e.g., 620‐585 Ma Central Iapetus5) or continental features (ca. 580 Ma Volyn6) and they were\nlikely rather a continuous drifting after the initial breakup before 720 Ma (ref.5). This is the\nreason to limit the Rodinia breakup phase to 940‐720 Ma, and to propose the 720 Ma plume as the\n‘terminal’ one of this breakup (that is, excluding post‐rift drift period) (Fig. 3). Lines 95‐109.\n[Reviewers #4]\n It is clarified that the Ethiopian plume is the ‘terminal plume’ of Pangea breakup. To avoid\nconfusion, we updated Figure 2: adding ‘Ethiopian/Afar plume’ in front of ‘(terminal plume)’, and\nadding the names of the LIPs produced by this plume in the figure. [Reviewer #4]\n A few references recommended by the reviewers were added. Bahlburg et al (2025)9 that\nproposed increasing crustal reworking/enrichment during the Rodinia breakup is added. This is\nthe newest publication after our submission, which supports a part of our observation. Broussole\n(2022)10 and Gardiner et al (2016)11 are also added. Lines 131‐134. [Reviewers #4]\nWe appreciate your valuable comments, which helped in improving the manuscript. Thank you again\nfor your kind help. We look forward to hearing from you.\nSincerely, and for my co‐authors,\nPeng Peng, Ph.D.\nREVIEWER COMMENTS\nReviewer #1 (Remarks to the Author)\nThis paper investigates the evolution of large low shear wave velocity provinces (LLSVPs) and their role\nin supercontinent cycles. The authors identify seven large igneous provinces (LIPs) associated with the\nRodinian supercontinent (940–720 Ma), forming a coherent ring used to infer the shape of the LLSVP\nat that time. Chemical proxies, such as Nd isotopes, indicate that recycled oceanic crust contributed\nto LIP formation during supercontinent breakup, suggesting that oceanic crust might be incorporated\ninto LLSVPs. The study highlights the interplay between mantle dynamics and supercontinental\nevolution.\nThe authors’ combined use of geochemistry and reconstruction of continents and LIPs to study LLSVPs\noffers a novel perspective, especially given that most previous studies have relied on numerical\nmodeling. I recommend the manuscript for publication after addressing some modifications and\nclarifications.\nMain Comments:\nThe term \"regeneration\" is unclear. Does it imply that the LLSVP was destroyed and then regenerated,\nor that it was simply modified through the addition of oceanic crust? From Figure 4 and the related\ntext, I infer that the regeneration refers only to the upper layer of the LLSVP, not the bottom layer.\nReply: Thanks. Here ‘regeneration’ refers to two aspects, 1) the replenishment of materials into the\nbasal mantle structure from subducted oceanic crust; 2) the shifting of the basal mantle structure\namong supercontinental cycles, mainly during the assembly stages. Yet, we are not sure if the\nreplenishment and migration only affected the shallow LLSVP domains or also influenced its bottom\ndomains, though the shallow domains must be significantly influenced.\nLines 314‐318: ‘Consequently, the ‘regeneration’ of LLSVPs through supercontinental cycles is featured\nby ‘replenishment’ by subducted oceanic crust (to mainly the shallow domains) through\nsupercontinental cycles but more prominent during their breakup, and the dynamic migration/forming\nof the shallow domains (probably the bottom domains as well) to couple the supercontinent lids\ndominantly during their assembly (Fig. 4)’.\nThis paper refers to the present‐day African LLSVP as the Pangean LLSVP, but Pangea broke up more\nthan 100 Ma ago. How are the Pangean and Rodinian LLSVPs defined, and when did the transition\nbetween them occur?\nReply: We define the Pangean/Rodinian LLSVPs constrained by LIPs during the breakup of the two\nsupercontinents respectively (in contrast to the African LLSVP defined by present‐day geophysical\ndata). Thus, the Pangean LLSVP is slightly different from that defined by present‐day seismic velocity,\ni.e., the African LLSVP (Fig. 1a). If there was significant shifting of LLSVPs during supercontinent cycles,\nthis must have happened during the assembly of the supercontinent(s) (Fig. 4). See also our reply to\nthe definition of ‘regeneration’ above.\nRegarding the paleogeographic reconstruction, does it align with paleomagnetic data, or are the\nmodifications directly adopted from other studies? Latitude should remain unchanged during these\nmodifications.\nReply: Thanks. The reconstructions in Figure 3a and b are exactly following those in the references\n(based on paleomagnetic data)1,8. That in Figure 3c (our synthesis model) is based on the\n3 / 18\nreconstruction in Figure 3a, with a few cratons (NCC, SCC, TA) relocated to fit the reconstruction of\nintact LIPs. All the relocated cratons are permissive paleomagnetic data or previous study based on\ngeology without enough paleomagnetic data, i.e., NCC12, SCC13 and Tarim14,15. This was addressed in\nthe caption of Figure 3 and emphasized in Lines 147‐151.\nLines 147‐151: ‘To construct as many associated units to a same LIP center as possible, a few cratons\nincluding North China 12 and Tarim 14 during 940–760 Ma and South China8,13 during 820–720 Ma are\nrelocated based on alternative possibilities based on the configuration of Evans 1 (Fig. 3c), which\nconstructs all vestiges of 940–720 Ma LIPs from different blocks into intact LIPs of each time,\ncompatible with the available paleomagnetic data.’\nPrevious studies suggest that both subduction (e.g., Merdith et al., 2021, ESR) and plume activities\n(Figure 1, and also Condie et al., 2021, Gondwana Research) are largely continuous processes without\nsignificant time gaps since Rodinia. Slabs may have continuously sunk into the deep mantle, modifying\nLLSVPs, although subduction rates (and locations) likely changed during supercontinent assembly and\nbreakup stages. This study primarily focuses on LIPs from supercontinent breakup stages. Could you\nexplain why LIPs from assembly stages are considered less significant?\nReply: Thanks. It is true that plumes16 and subduction zones17 are more or less continuous over the\nlong term (e.g., over 100 Myr), especially since the assembly of Rodinia. We considered that the LIPs\nformed during breakup stages are more important in constraining the shape of the LLSVPs as, 1) there\nwere more LIPs during the breakup stages than the assemblies18,19; 2) the LLSVPs may be more\ndynamic and their regenerations including both their shifting were more significantly happened during\nthe stages of assembly (see our comments to the definition of regeneration in the above point) than\ntheir breakup, while its replenishment would be on the contrary.\nIn the last paragraph, the authors state, “the shallow domains of the Pacific LLSVPs were not able to\nbe regenerated due to the absence of subducting oceanic crust into the region.” This statement is not\nentirely accurate. Numerical models show that, while subduction mostly dips toward continents in the\nupper mantle, some slabs flow toward the Pacific LLSVP in the deep mantle. It is probably true that\nfew slabs descend directly above the Pacific LLSVP to sink onto its top surface.\nReply: Thanks. But still, there are no significant subducting slabs into the Pacific LLSVP. We modified\nthe statement a little bit – ‘due to the absence of significant subducting oceanic crust into the region’.\nMinor:\nAbstract: The last sentence is complex and could be restructured for better clarity.\nReply: Revised. The sentence is split into two.\nLines 25‐30: There is a same secular variational pattern of LIP sources with a replenished depleted\ncomponent advected by plumes as well as a similar manner yet contrasting paleogeographic\nconfigurations corresponding to supercontinental breakup between Rodinian and Pangean LLSVPs.\nThis evolving pattern of LLSVPs suggests their partial regeneration (replenishment and migration)\nbetween supercontinents.\nFigure 1: The figure shows plate speed, but it seems to only represent the speed of major continents.\nSince there is little Jurassic and older oceanic crust preserved. If you look at the Fig.7 of Muller et al.\n2022, the global plate speed (both continent and ocean) in the Cretaceous is pretty high.\n4 / 18\nReply: Yes, it refers to speed of major continents. This is specified in the caption.\nLine 75, “while its LLSVPs”, does this mean Pangean LLSVPs?\nReply: Yes, it refers to the African LLSVPs. We revised to say ‘the present’ LLSVPs.\nLine 101, This is Figure 2, not 3. The breakup of Rodinia around ~900 Ma seems somewhat early. In\naddition, in the top‐left corner of the figure, the phrase “adding of reclyled … during Rodinia assembly”\nis paired with two arrows, and the right arrow points to Pangea (not Rodinia) assembly.\nReply: Yes, Corrected. This is Figure 2. And as for the arrows, yes, they are pointing to two different\nassembling supercontinents. Consequently, we revised to say during ‘supercontinental’ assembly.\nLine 149, 940‐890 Ma?\nReply: Yes, revised to 940–890 Ma.\nLine 177, the statement, \"the fact that Pangea and Rodinia are supercontinents of broadly similar\nhemispheric‐scale size,\" may not be accurate, particularly for Rodinia. Reconstructions of Rodinia are\nmodels and remain subject to significant uncertainty.\nReply: Thanks. t is not exactly accurate as the various reconstructions of Rodinia are diverse. However,\nthe core members of Rodinia are more or less similar (c.f., 1), and thus too their collective sizes.\nNevertheless, we change to say, ‘the estimation that Pangea and Rodinia…’.\nLine 224: not all mantle material extracted from LLSVPs becomes LIPs; some material is mixed with the\nambient mantle instead.\nReply: Fair point. There could be some materials that leak into the ambient mantle; however, the\nfraction of such materials can hardly be constrained. In the revision, we correct to say ‘the melts\nextracted from LLSVP to produce LIPs or join the ambient mantle…’.\nLines 236–239, how the ascent rate of plumes is linked to the timing of increases in LLSVP influx and\noutflux?\nReply: Here was a little bit confusing. We connected the ascent rate of plumes to the rate of outflux,\nwhich followed the changes in the rate of influx. We modify the sentence a little bit ‘the higher outflux\nfrom LLSVPs through plumes during the breakup stage (Fig. 1) is closely following the increasing influx\nof subducted slabs since the assembly, neglect as the ascent timing of a plume that can be as fast as\nwithin a couple of million years’.\nLine 257, the term “these drifted cratons” is unclear\nReply: Thanks. We add ‘in Figure 3d (stage 3)’ after ‘these since‐drifted cratons’.\n5 / 18\nReviewer #2 (Remarks to the Author)\nReview for ‘Basal mantle structure regenerated through supercontinents’\nSummary of the manuscript:\nThe manuscript by Peng et al. presents an investigation into the long‐term dynamics of LLSVPs through\nthe comparison between basal mantle structures beneath the Pangean and Rodinian supercontinents.\nNew geochemical analysis from samples at 2 LIP sites are presented along with previously published\nanalysis to allow comparison of geochemical properties of LIPs spanning the breakup of Rodinia (and\nPangea). The results suggest that the palaeogeography of both LLSVPs can be recreated from the\nlocation of LIPs, and that they follow similar geochemical evolutions. They propose that these\nsimilarities require a regeneration of LLSVPs between supercontinents, driven by subduction dynamics.\nThis work represents a significant contribution to the ongoing discussions about the relationship\nbetween LLSVPs, LIPs and continental break‐up. The model presented, along with the accompanying\ngeochemical evidence, will be of interest to the community.\nA comment on expertise. The method of geochemical analysis lies outside of our area of expertise;\nhowever, we are very comfortable commenting on the manuscript which principally focusses on\nunderstanding the evolution of LLSVPs and from the perspective of LIP driven super‐continental\nbreakup.\nReply: Thanks for the general comments.\nNote that the line numbers in the PDF and Word document are not the same – the line numbers below\nrefer to those in the PDF file.\nPaper presents new geochemical data but this is not mentioned in the abstract – this is an important\naspect of the work.\nReply: Good point. In the revised abstract, we added ‘with new and compiled data a series of seven\nLIPs …’.now emphasize the new data too.\nLine 67: Figure 1 subfigures not labelled (e.g. a, b, c) so the figure caption is hard to follow. Axis label\nimplies number of orogens but the caption says you are plotting orogen lengths? Are secondary y‐axes\nsame for number of LIPs and probability?\nReply: Thanks. Now, we added a, b, and c to subfigures to help guide the reader.\nThe caption has been corrected as ‘number of orogens’ to make consistent with the axis labeled.\nThe secondary y‐axes refers to ‘relative probability’, which is non‐numerical, and is different from that\nof the LIPs. We added ‘relative’ in front of ‘probability’ to avoid confusing with ‘absolute probability’.\n6 / 18\n(revised Figure 1)\nLines 69‐70: Is this really an anticorrelation? Especially dubious for the orogen length. A correlation\ncoefficient would be helpful if possible.\nReply: The main peak of both orogens and speed of plates is during 300–600/700 Ma, which is the\ntrough for LIPs (Fig. 1c).\nFigure 2: This is incorrectly labelled as Figure 3. The inset plot of Mg#, Ni, Nb/Ta, Gd/Yb need better\nseparation from the plot of εNd, it is confusing to read at first. Perhaps the shading around the εNd\nplots could be darker too for emphasis.\nReply: Thanks. Yes, Figure 2 was incorrectly labeled as Figure 3.\nThe inset plot of Mg#, Ni, Nb/Ta, Gd/Yb is better separated from the plot of εNd. And the shading for\nthe εNd are slightly darkened.\nFigure 3. The plots in the right‐hand column need to have sub‐plot numbers. On the reconstructions\nof the LIP locations in the synthesis model. The locations plotted in 3c (bottom left) assume that the\nplumes move with the plate motions as Rodinia undergoes breakup. Is this an assumption that you\nmake? If we understand correctly, the locations plotted here are the locations of the LIPs Would a\nbetter estimate for the LLSVP boundaires be from plotting the absolute eruption locations of the LIPs\nrather than their location relative to the cratons while Rodinia was still intact? This would certainly\nlead to a different shape of your LLSVP.\nReply: Thanks. The sub‐figures in the right‐hand column are also labeled (d, e, and f).\nYes, the LIP locations during breakup give a slightly different shape of the reconstructed LLSVP. So we\nnow make it clear that these are two approaches to defining LLSVPs with LIPs — either ‘restored’ LIP\nlocated to supercontinent configuration or ‘real‐time’/’contemporary’ LIP locations during\nsupercontinent breakup — and address which one we might prefer. Based on empirical study for the\n7 / 18\nPangea, the shape of present‐day African (Pangean) LLSVP is better analogue of the shape defined by\nLIPs on an intact reconstructed Pangea some 200 million‐years‐ago2,3. This is probably indicating that\nthe basal mantle structure was formed at the time the supercontinent was assembled, and it was not\nsignificantly changed during the breakup, except that the rising plume may be coupled with the motion\nof the overriding plate (e.g., a trailing plume head of the Hawaiian plume, Ref 4).\nLines 330‐342: ‘ It should be mentioned that there are potentially two ways to reconstruct the LLSVPs\nbased on LIP centers: either (i) by ‘restored’ ‘apparent’ LIP centers located on an ‘intact’ Rodinia\nreconstruction (Fig. 3c), or by the ‘real‐time’/‘contemporary’ LIP centers located at each LIP age\nthroughout Rodinia breakup (Fig. 3f). The two approaches yield slightly different reconstructed LLSVPs\n(Fig. 3f). Here are reasons we may prefer those LLSVPs defined by LIPs on the intact supercontinental\nreconstructions (Fig. 3a‐c). Firstly, this has an empirical basis from the Pangean LLSVP, where the shape\nof present day African LLSVP more closely matches the shape defined by LIPs on a full reconstructed\nPangea ca. 200 million‐years‐ago2,3. Secondly, the ‘regeneration’ model indicates that the basal mantle\nstructures were formed and less dynamics since the assembly of the supercontinent, and only the\nrising plumes (and thus LIP centers) may have been affected by the motion of the drifting lithosphere20,\nfor example, plumes have trailed due to coupling with motion of overriding plate motion (e.g., the\nHawaiaiian plume4), which explains the differences of the two reconstructed LLSVPs (Fig. 3f)’.\n(revised Figure 3)\n8 / 18\nLines 249‐251: Needs clarifying. Need to quantify the volume of the LIPs if you want to make this\ncomparison. Also, models do not suggest that all subducted oceanic crust would be incorporated into\nLLVPs and estimating the volume of melt produced by LIPS is different to estimating the amount of\nmaterial advected away from LLVPs. You can highlight the similar trends but cannot compare the mass\nfluxes.\nReply: Yes, here in this paragraph, we are comparing the variation trends of especially Nd isotopes in\nLLSVPs after the increasing influx or outflux of materials, not a quantitative calculation based on\nabsolute volumes. In the revision, we changed to say ‘these may indicate a comparable trends in\nvariation of volumes of subducted oceanic crust during the accretion of continental crust of the two\nsupercontinental cycles ’ (Lines 250‐252). And we added ‘However, a quantitative calculation of\nmaterial fluxes in and out of the LLSVPs is beyond the scope of the paper’ (Lines 282‐283) .\nThe ‘regeneration model’ should be explained a little bit in more detail in the main text – not just\nconsigned to the figure caption of Fig 4. There are some details missing such as how can the model\naccount for material which is subducted whilst the supercontinent is extant?\nReply: Thanks. A definition of ‘regeneration’ is added, which includes both replenishment of materials\ninto the LLSVPs, as well as the possible dynamic shifting of the basal mantle structure. In our model,\nthe influx and outflux of materials of the LLSVP is dynamically coupled. For example, the increasing\nrate of influx was followed by the increasing rate of outflux, though there would be a time lag. Likewise,\nthe materials subducted during breakup were also able to contribute the basal mantle structure (influx)\nand also advected in the plumes but less prominent and mainly during the assembly stages (outflux).\nLines 314‐318: see above.\nGenerally, there are quite a few sentences which have quite difficult wording and are often too long\nso that the point of the sentence is unclear or obscured. Some of these have been noted below.\nReply: Thanks. We have checked through the manuscript and made necessary corrections.\nMinor comments:\nLines 19‐20 : This wording could implies that the basal mantle structures come directly from the\nsupercontinents ‐ I don't think that is what you mean.\nReply: Thanks. ‘Responded’ is added: ‘How such basal mantle structures evolved back to and\nresponded to earlier supercontinents is unknown’.\nLines 29‐33: This sentence is very weighty and so obscures the point you are trying to make.\nReply: Thanks. This sentence has been split into two sentences.\nLines 25‐30: see above (the comment to Reviewer #1).\nLine 36: Would argue that they are geophysical structures.\nReply: Sure they are revealed by geophysics, but they must also be geological structures. Here, we\nrevise to say ‘geophysical/geological structures’.\n9 / 18\nLine 72: Should specify that it is data for the seven Rodinian LIPs which is presented.\nReply: Thanks. ‘Rodinian’ added.\nLine 74– 76: This makes it sound like you have a seismic velocity model for when Pangea was extant.\nAre you assuming that the LLSVPs are fixed?\nReply: Thanks. Here we need to avoid indicating the fixation of LLSVPs. In the revision, we added\n‘present’ in front of ‘LLSVPs determined by seismic velocity’ to distinguish from those\n(Rodinian/Pangean) determined by ‘LIP’ reconstruction.\nLine 79: what do you mean by ‘internally consistent in chemistry’. Does not seem to agree with the\nchanges in chemistry with time that you observe.\nReply: The ‘internally consistent in chemistry’ is limited to vestiges of each LIP, while there are changes\nfrom a LIP to another.\nLines 82‐83: ‘increase of diversified features’ with increasing age.\nReply: Thanks. ‘With increasing age’ is added.\nLines 83‐85: This sentence is slightly unclear. We think that you are saying that the Rodinian LIPs have\na common source which is chondritic?\nReply: Yes, we meant that the Rodinian LIPs have a common source similar to chondrite. We think it\nwas the phrase ‘for example’ which makes the sentence confusing. Consequently, ‘for example’ is\ndeleted.\nLines 93‐95: This sentence needs references to support the point.\nReply: It refers to ‘Methods: Application of geochemical proxies’.\nLine 113‐115: This sentence needs a reference.\nReply: We refer this sentence to the figure. ‘As for the array of the enriched sources in the figure…’.\nLine 155: ‘Totally seven Rodinian LIPs’ is not very clear\nReply: We refer this to Figure 1b.\nLine 156: ‘Coincide with a trench in both orogen lengths and plate speeds’, can see a trough in orogen\nlength but not so clear for the plate speeds.\nReply: Thanks. ‘Plate speeds’ deleted.\nLine 182: Fig 3c – is that the right subfigure?\nReply: Yes, now they are also numbered independently. Changed to Figure 3d & f.\nLine 235: ‘... roughly similar peaks’. Peaks in what?\n10 / 18\nReply: Peaks ‘of abundance’. Added.\nLines 244‐246: This is unclear. Are you saying that the primordial source is not significantly altered\nthrough time and is not enough alone to explain the trends?\nReply: Yes. We change to say ‘If we assume that there were negligible outflux/influx of materials from\nthe bottom domain despite minor materials into plumes,….’.\nLine 264 266: See Mulyukova et al., 2015 (JGR Solid Earth) and Panton et al., 2025 (Scientific Reports)\nfor geodynamic which are argued to support ‘regeneration’ (or replenishment).\nReply: Thanks. The two references on ‘replenishment’ and ‘rebalance’ of the basal mantle structure\nby subducting oceanic crust are added.\nLines 296‐298: ‘Modeling of mantle flow has suggested that the basal mantle structure could have\nbeen replenished and rebalanced by subducted oceanic crust21,22 and could have changed over time\ndue to the changing subduction network over supercontinental cycles23; …’\nLines 266 – 271. The sentence is quite clunky, needs splitting up and rewriting. Also reference 46 is a\nsimulation which does not explicitly subduct oceanic crust, rather it is initialised with a layer of ‘ocenaic\ncrust’ above a ‘primordial’ layer – so I think these simulations are not appropriate for the point you\nare trying to make.\nReply: Split into two sentences. And the reference 46 is deleted here.\nLines 299‐304: ’Since the subducted oceanic crust might have mainly influenced the compositions of\nthe shallow domain of the LLSVP24,25, the shallow Rodinian LLSVP was formed during the breakup of\nthe supercontinent driven by accumulatively piled oceanic crust. Likewise, the shifting/migration of\nthe LLSVP from the Rodinian breakup to Pangean assembly was driven by the subduction system,\nfollowed by its replenishment of the LLSVP during the breakup of Pangea (Fig. 4)’.\nBest of luck with the submission, James Panton and Abigail Plimmer.\nReviewer #3 (Remarks to the Author):\nI co‐reviewed this manuscript with one of the reviewers who provided the listed reports. This is part\nof the Nature Communications initiative to facilitate training in peer review and to provide appropriate\nrecognition for Early Career Researchers who co-review manuscripts.\nReply: Thanks for reviewing. It really helps.\n11 / 18\nReviewer #4 (Remarks to the Author):\nDear authors,\nThe content is interesting and well written, figure are well presented but could be performed. The\nEnglish can also be polished a little. The author should clearly define what is “regeneration”. Geological\nand/or geochemical consequences expected? The paper considers that Gondwana is not a\nsupercontinent. However, it is clear from figure 1 that there are a lot of orogens formed at 600 Ma.\nThe author needs to discuss this point in details. Why LIPS and orogens are formed at the same time\nat 600 Ma if the break ups of Rodinia terminate at 700 Ma?\nReply: Thanks.\n1) ‘Regeneration’ is defined. The ‘regeneration’ of LLSVPs is defined as ‘replenishment’ of subducted\noceanic crust mainly to the shallow domains, and the dynamically shifting of the shallow domains\n(probably the bottom domains as well) of them predominantly during the assembly of their\ncoupled supercontinents’. This process may couple the basal mantle structure with the\nlithospheric plates.\nLines 314‐318: see above (the comment to Reviewer #1).\n2) It is true that there are both orogens and plumes during the forming of Gondwana (Fig. 1c).\nActually, there are also a number of LIPs during the assembly of supercontinents. However, these\nLIPs may not associated with breakup but merely a protracted stage after initial breakup or\nassociated with assembly tectonics (e.g., subduction, oceanic plateau, etc.). For example, some\nLIPs at assembly stages have been involved in a subduction system (e.g., 258 Ma Emeishan7) or\neven just preserved oceanic plateaus (e.g., ca. 230 Ma Wrangellia26), while some others may\nrepresent a continuous plume process after initial breakup (e.g., 620‐585 Ma Central\nIapetus/Kaavi‐Kuopio5; <80 Ma LIPs associated with the Kerguelun plume27) or just intraoceanic\n(e.g., Hawaiian‐Emperor28). These are assembly‐stage plumes, and they are not considered in the\nhypothesis. We have updated Figure 2 to show some of the above LIPs, and added several lines to\ndepict this point.\nLines 95‐109: ‘Figure 2 shows that the LIPs during assemblies have quite different features of Nd\nisotopes from those during the breakup: Those immediately following the breakup of Rodinia\nshow primitive to enriched compositions; while those right prior to breakup show enriched‐\ndominated but varied compositions (Fig. 2). This increase of enrichment following breakup but\ncome back to increase of depletion could result from assembly‐associated processes: Either 1)\ngenerated from relatively primitive sources (e.g., Central Iapetus/Kaavi‐Kuopio5) or continental\nlithosphere (e.g., Volyn6) at the late stages of plumes associated with breakup; or 2) involvement\nof both subduction system and continental lithosphere (e.g., Emeishan7) prior to breakup.\nMultiple models suggest a protracted breakup tenure of the Rodinia supercontinent to as young\nas ca. 600 Ma1,8; however, the 700–510 Ma LIPs show features of primitive sources (e.g., Central\nIapetus 5) or continent (Volyn 6) and they were not likely related to breakup but rather continuous\ndrifting since the initial breakup before 700 Ma (ref.5), or they have been ‘weakened’ with less\nprimitive or depleted sources (Fig. 2). This is another reason to limit the breakup of Rodinia to\n940–720 Ma, and to propose the 720 Ma Franklin plume as the ‘terminal’ plume of this tenure\n(Fig. 2)’.\n12 / 18\n(updated Figure 2)\nSecondly, If the breakup occurs at 940‐720 Ma then what happens to the LIPS formed at 600 Ma that\nare usually considered as protracted breakup of Rodinia. Especially, if there is a terminal plume formed\nbefore 600 Ma (i.e., 700 Ma). In this new model, how to interpret the 600 Ma LIPS ? A reappraisal of\nthe 600 Ma LIPS should be done and mentioned.\nReply: Thanks. To better address this point, we have collected available data for the LIPs from the\nassembly and tenure stages of both the Pangea and Rodinia supercontinents (Fig. 2). The LIPs during\nthe assembly of the Gondwana show primitive to enriched Nd isotopes. It indicates a source from\nmore primitive mantle in the LLSVP or from crust, and these LIPs did not necessarily result in breakup,\nbut merely a continuous process after an initial breakup of the continent. For example, the 620–585\nMa central Iapetus LIPs are thought to be representing a plume source after the initial breakup of the\nIapetus ocean at 750–720 Ma (ref.5). Consequently, these plumes/LIPs cannot be regarded as a part\nof the breakup stage.\nLines 95‐109: see above.\nThe author have to mention the paper which also suggest that the decrease of Hf isotopes occurs\nduring break up of supercontinents. (i.e., Bahlburg et al., 2025). Thus, it is not the first paper to propose\nreworking during breakup. Although Bahlburg only proposes decrease of Hf isotopes during breakup,\nthe submitted manuscript proposes widening of the Hf array and increase reworking towards younger\ntime which is new. Please mention that paper in your manuscript.\nReply: Thanks. We are happy to see that Bahlburg et al (2025) 9 have come independently to a similar\nobservation to us that there is also an increase in crustal reworking during breakup, though it is merely\nabout the continent rather than the LIPs. We are therefore delighted to cite it.\n13 / 18\nLines 131‐134: ‘Similar patterns of increasing enrichment (reworking) in continental lithosphere during\nsupercontinental breakup9 while increasing depletion (accretion) during assembly‐tenure phases10,11\nare supported by Hf isotopes’.\nThe author should say what it means by regeneration, by giving a clear definition of the process and\nthe geological consequence of regeneration of the mantle structure LLSVPs.\nReply: Thanks. See reply above, and lines 314‐318 (see above, the comment to Reviewer #1).\nFigures:\nFigure 2 and 3 have the same number which is 3, it should be corrected because it is difficult to review\nthe paper.\nReply: Sorry for this mistake. We have corrected the number of Figure 2.\nFigure 1:\nMy first question is about the fact that the peak of orogens occur at 600 Ma. How do you explain this\nin the framework of having also LIPs formed at 600 Ma, although its not many. In addition, Condie et\nal. 2021 have a different dataset for the LIPS province with data almost continuous during the Earth\nevolution. Why your dataset varies? How to interpret the dataset from Condie et al. 2021 and the one\nused in your study?\nReply: Thanks. Yes, there are orogens at ca. 600 Ma which reflects the assembly of megacontinent\nGondwana and hence its supercontinent Pangea. The LIPs formed during the assembly of a\nsupercontinent is not necessary indicating continental breakup (e.g., the 620–585 Ma Central Iapetus\nLIPs5) or rather plume activities associated with a protracted breakup (e.g., the Kerguelun plume and\nits youngest LIPs27). As for the dataset of Condie et al (2021)16, the peaks are rather similar to ours,\nonly it just emphasizes the ‘continuously’ happening of the LIPs/plume activities during both assembly\nand breakup. However, we intend to separate breakup associated LIPs (during the breakup tenure)\nand the LIPs during the assembly stage as they show different features (Fig. 2). Please see also our\nreply to the comment following, and the action taking in the revision.\nLines 95‐109: see above.\nFigure 2:\nI agree with this graphic, but why did you not plot the LIPs at 600 Ma as well? Maybe it could show no\ntrends at Gondwana, supporting you interpretation of Rodinia through Pangea. It is a possibility to\nsupport your model of Gondwana not being a supercontinent and part of the assembly of Pangea.\nReply: Thanks. There are not so many large LIPs with Nd isotopes reported between 700–200 Ma.\nNevertheless, we added 700–200 Ma LIPs with Nd isotopes. It shows that these LIPs have more\nvariable isotopic signature; while the LIPs during Gondwana assembly have primitive to enriched\nsources, which shows a trend different from the Rodinia LIPs. This variation could be produced by\nassembly tectonics, for example, some of them might have been involved in a subduction system (e.g.,\ngenerate melts from more primitive source and/or continent after the initial breakup during 940‐700\nMa (e.g., 620‐585 Ma Central Iapetus/Kaavi‐Kuopio5). These LIPs di not likely result in breakup,\neven for the LIPs from 620–585 Ma5.\n14 / 18\nLines 95‐109: see above.\nI did not find a reference for “Terminal Plume” in the literature for Pangea. Ethiopia has 3 vertical bar?\nPlease name each bar in the graphic as you did from 900 to 700 Ma. You should give a proper reference\nof this “plume” for Pangea. If terminal plume is a prediction of the composition of the plume at 0 Ga\nand not a geological record should be stated clearly in the manuscript? If I missed the reference, kindly\nshow us the reference.\nReply: Sorry, ‘terminal’ is not a name of a plume but rather a ‘plume’ at the final stage of breakup.\nHere all the four bars/LIPs are products of the ‘(terminal plume)’, the Ethiopia/Afar plume 29,30. To\navoid such a misreading, we have added the four names for these hotspots/LIPs, i.e., Southern Ethiopia,\nNorth Kenya‐Ethiopia‐Yemen, Central Kenya, and Northern Tanzania. See Figure 2 (above).\nFigure 3:\nAlso explain clearly what is the underlying hypothesis to consider a synthesis model and not only one\nof the two previous models of Li et al. 2023, or Evans et al. 2021. A plume is circular, therefore LIPS\nshould be centred on the plume head ?\nReply: Utilizing the previous models such as Li et al (2023)8 and Evans et al (2021)1 leads to a similar\nconclusion on the ‘regeneration’ hypothesis of this study. However, we find that if we relocate a few\nless‐constrained cratons with flexible data (both paleomagnetic and geologic observations), it can give\na better correlation of the distribution of the seven Rodinian LIPs, i.e., these vestiges of a same LIP\ncome to a same plume center. This is also consistent with the empirical conclusion from the Pangea\ncycle that the LIPs during supercontinental breakup depict the shape of the LLSVPs, as well as the\nmanner of drifting. This has been explained in the caption of Figure 3 and text (Lines 147‐151, see\nabove, the comment to Reviewer #1).\nText :\nLine 167: This phrase does not read well. Could you change it?\nReply: ‘LLSVP test’ changed to ‘test’.\nLine 219: change two more basics, which reads strangely.\nReply: ‘Basics’ changed to ‘essentials’.\nLine 228: “However, it needs to be mentioned that the influx of oceanic crust should be larger during\nbreakup than assembly stages of supercontinents cycles”.\nI strongly advise to add these two references to support your claim: Broussolle, 2022 and Gardiner et\nal. 2016. Indeed, these two references support that reworking occurs during assembly of\nsupercontinents and Gardiner et al. 2016 shows that arc setting forms juvenile signatures.\nReply: Thanks. The two references focus on the evolution of continents and the accretion of juvenile\ncrust into the continent. They are not very relevant to this sentence on the evolution of oceanic crust\nand LIPs. However, Broussole (2022) is about support the enrichment valley in the continental\nlithosphere during assembly; while Gardiner et al (2016) is able to support our conceptualization on\nthe depletion of continent during breakup stages in Figure 3 and caption.\nLines 147‐151 (see above, the comment to Reviewer #1).\n15 / 18\nLine 239: explain timely “refreshed” here\nReply: ‘Refreshed’ changed to ‘Replenished’.\nLine 245: negatable should be changed too\nReply: ‘Negatable’ changed to ‘negligible’.\nLine 247: the sentence does not reads well, could you change it please.\nReply: Yes, it is reworded.\nLines 277‐279: ‘The above arguments indicate that the Pangean LLSVP could not be explained by\ninheritance from Rodinian LLSVP but rather with the replenishment of materials during accumulative\nassembly tectonics (Fig. 2)…’.\nLine 299 The shallow domain is generating during the breakup stages.\nHere generating should be modified for generated ?\nReply: Thanks. Changed to ‘generated’.\nReferences :\nBroussolle, A. (2022). Mathematical modelling reveals potential acceleration of the supercontinent\ncycle. Scientific Reports, 12(1), 17391.\nBahlburg, H., Kemp, A. I., Fanning, C. M., & Martin, L. (2025). The Hf and O isotope record of long‐\nlasting accretionary orogens: The example of the Proterozoic and Paleozoic‐Triassic central South\nAmerica. Earth‐Science Reviews, 105068.\nCondie, K. C., Pisarevsky, S. A., & Puetz, S. J. (2021). LIPs, orogens and supercontinents: The ongoing\nsaga. Gondwana Research, 96, 105-121.\nGardiner, N. J., Kirkland, C. L., & Van Kranendonk, M. J. (2016). The juvenile hafnium isotope signal as\na record of supercontinent cycles. Scientific reports, 6(1), 38503.\nTable\nSupplementary material 4 take out the comments with “outlier”.\nReply: Comments deleted. Thanks.\nBest regards,\nArnaud Broussolle\nReferences\n(2021).\nbreakup initiation and propagation. Gondwana Research 96, 56-75 (2021).\nhttps://doi.org:10.1016/j.gr.2021.04.003\nPangea of competing reference frames with the African LLSVP. Geoscience Frontiers 11,\n1253-1256 (2020). https://doi.org:10.1016/j.gsf.2019.12.002\n16 / 18\nplume. Earth and Planetary Science Letters 295, 231-240 (2010).\nhttps://doi.org:10.1016/j.epsl.2010.04.005\nLamproites and Related Magmas From the Finnish Segment of the Karelian Craton.\nGeochemistry, Geophysics, Geosystems 23, e2021GC010324 (2022).\nhttps://doi.org:https://doi.org/10.1029/2021GC010324\nVolyn area. Mineralogical Journal (Ukraine) 34, 50-68 (2012).\nCentral Tibet: Evidence for Interaction Between the Emeishan Plume and the Paleo‐\nTethyan Subduction System. Journal of Geophysical Research: Solid Earth 123, 6540-\n6561 (2018). https://doi.org:10.1029/2018jb015568\namalgamation to the age of supercontinent cycle. Earth-Science Reviews 238 (2023).\nhttps://doi.org:10.1016/j.earscirev.2023.104336\nlong-lasting accretionary orogens: The example of the Proterozoic and Paleozoic-Triassic\ncentral South America. Earth-Science Reviews 262 (2025).\nhttps://doi.org:10.1016/j.earscirev.2025.105068\nsupercontinent cycle. Sci Rep 12, 17391 (2022). https://doi.org:10.1038/s41598-022-\n21662-x\nSignal as a Record of Supercontinent Cycles. Sci Rep 6, 38503 (2016).\nhttps://doi.org:10.1038/srep38503\nBrazil: Implications for the Paleogeography of Rodinia. Journal of Geophysical Research:\nSolid Earth 127 (2022). https://doi.org:10.1029/2022jb025079\nbetween Australia–East Antarctica and Laurentia? Geology 23, 407-410 (1995).\nhttps://doi.org:10.1130/0091-7613(1995)023<0407:Scirpo>2.3.Co;2\nMozambique orogens and growth of megacontinent Gondwana. Communications Earth &\nEnvironment 4 (2023). https://doi.org:10.1038/s43247-023-00883-6\nTarim, NW China: A missing link between São Francisco, Congo and North China\ncratons. Precambrian Research 333 (2019).\nhttps://doi.org:10.1016/j.precamres.2019.105428\nongoing saga. Gondwana Research 96, 105-121 (2021).\nhttps://doi.org:10.1016/j.gr.2021.05.002\nNeoproterozoic and the Phanerozoic. Earth-Science Reviews 214 (2021).\nhttps://doi.org:10.1016/j.earscirev.2020.103477\nsupercontinents: Toward completing the plate tectonic revolution. Lithos 174, 1-14\n(2013). https://doi.org:10.1016/j.lithos.2013.02.017\nsuperocean episodes. Precambrian Research 323, 1-5 (2019).\nhttps://doi.org:10.1016/j.precamres.2019.01.009\nand Viscosity on Mantle Dynamics Throughout the Supercontinent Cycle. Geochemistry,\nGeophysics, Geosystems 25 (2024). https://doi.org:10.1029/2024gc011688\nbillions of years in a vigorously convecting mantle: Replenishment and destruction of\n17 / 18\nchemical anomaly. Journal of Geophysical Research: Solid Earth 120, 3824-3847 (2015).\nhttps://doi.org:10.1002/2014jb011688\nand evolutionary histories of large low velocity provinces. Sci Rep 15, 4466 (2025).\nhttps://doi.org:10.1038/s41598-025-88931-3\nin response to supercontinent aggregation and dispersal. Sci Rep 11, 22967 (2021).\nhttps://doi.org:10.1038/s41598-021-02359-z\ncycling oceanic crust through mantle reservoirs. Nature Geoscience 7, 366-370 (2014).\nhttps://doi.org:10.1038/ngeo2120\nheads trigger compositionally distinct secondary plumes? Science Advances 6,\neaba0282 (2020).\nplume‐lithosphere interaction in a Late Triassic accreted oceanic plateau.\nGeochemistry, Geophysics, Geosystems 9 (2008). https://doi.org:10.1029/2008gc002092\nSci Rep 11, 10796 (2021). https://doi.org:10.1038/s41598-021-90172-z\nBend and LLSVPs are not fixed. Nat Commun 10, 3370 (2019).\nhttps://doi.org:10.1038/s41467-019-11314-6\nvolcanism explained by a single, migrating plume. Geoscience Frontiers 11, 1669-1680\n(2020). https://doi.org:10.1016/j.gsf.2020.01.003\npulsed magmatism. Lithos 286-287, 264-301 (2017).\nhttps://doi.org:10.1016/j.lithos.2017.05.014\n18 / 18"}, {"round": 2, "reviewer_comments": {"reviewer_1": "The authors have addressed all of my previous comments appropriately", "reviewer_2": "Thank you for all of the amendments that you have made to your submission. These have cleared up some of the uncertainties we had about the reasoning and assumptions you had used in your synthesis model. Below are a few outstanding comments that we have on the re-submission.\n69-70: The wording ‘anticorrelation’ here we still think is too strong, unless it can be backed up with a quantitative value. The anticorrelation is much clearer between 0-500Ma than it is 500 - 1300 Ma. The wording in the caption suggests that LIP occurrence and number of orogens is anticorrelated through time, but in the text you are more specific in saying that the LIPs associated with supercontinent breakup occur during periods of low orogen count. While we agree with you on the latter, the suggestion that LIP occurrence and number of orogens are anticorrelated through time we remain to be convinced of. Also on line 179 you refer to ‘orogen lengths’ but I think after changes made in the figure you mean number of orogens.\n89-91: References are needed for this sentence.\nLns 95-109: We think that it needs to be made explicit why you are choosing to exclude LIPs associated with Gondwana assembly.\nLns 330-342: Thank you for including both approaches to defining the LLVP boundaries based on LIP eruptions and including some reasoning for choosing one over another. We think the descriptions of the distinctions between the two approaches could be a bit clearer, there are a lot of words being used in an attempt to summarise the differences between the two approaches, eg. ‘restored’ ‘apparent’ ‘real time’ ‘contemporary’, but perhaps a slightly more in depth description would be helpful to the reader.\nMinor:\nLn 41: ‘hereafter’ rather than heretofore.\nFig. 4 - Some text is difficult to read.\nResponses to other reviewers:\nWe would also like to emphasise our support for some of the points raised by other reviewers, in particular:\nThe response to reviewer 1 about why you consider LIPs during breakup to be more significant that those during assembly.\nIt might be useful to justify this in the text.\nThe velocities plotted in Fig 1 are estimates for the velocities of the continents and you have noted that as such in the figure caption, however is this really the correct measure to be using. Would global plate speed (inclusive of oceanic plates) be more appropriate?", "reviewer_3": "I co-reviewed this manuscript with one of the reviewers who provided the listed reports. This is part of the Nature Communications initiative to facilitate training in peer review and to provide appropriate recognition for Early Career Researchers who co-review manuscripts.", "reviewer_4": "Thanks to the review, the manuscripts better presents the replenishment of the LLSVP, and also discusses the difference between plumes from the breakup and plumes from the later stage evolution. They show different eNd values, which was shown in figure 2 and explained in the manuscript.\nThe addition of these data, strengthen the current model presented by the authors.\nall my comments were addressed and thus, I have nothing less to say before acceptance.\nBest regards,\nArnaud Broussolle"}, "author_response": "Dr. Peng Peng, Professor (pengpengwj@mail.iggcas.ac.cn)\nInstitute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China\nPoint-to-point reply (Reponses in blue Revisions in red)\nReviewer #1 (Remarks to the Author):\nThe authors have addressed all of my previous comments appropriately\nReply: Thanks.\nReviewer #2 (Remarks to the Author):\nThank you for all of the amendments that you have made to your submission. These have cleared up\nsome of the uncertainties we had about the reasoning and assumptions you had used in your synthesis\nmodel. Below are a few outstanding comments that we have on the re-submission.\n69-70: The wording ‘anticorrelation’ here we still think is too strong, unless it can be backed up with a\nquantitative value. The anticorrelation is much clearer between 0-500Ma than it is 500 - 1300 Ma. The\nwording in the caption suggests that LIP occurrence and number of orogens is anticorrelated through\ntime, but in the text you are more specific in saying that the LIPs associated with supercontinent\nbreakup occur during periods of low orogen count. While we agree with you on the latter, the\nsuggestion that LIP occurrence and number of orogens are anticorrelated through time we remain to\nbe convinced of. Also on line 179 you refer to ‘orogen lengths’ but I think after changes made in the\nfigure you mean number of orogens.\nReply: Thanks. Yes, we changed ‘orogen lengths’ to ‘number of orogens’. After a comment following,\nwe also change to use speeds of all plates through time from Ref.1, which give a better ‘anti-correlation’\nwith the numbers of LIPs. But we agree that the point here is that the ‘PEAK’ of LIP occurrence is ‘anti-\ncorrelated’ with number of orogens and speed of plate. We keep the description in the text, but\nchange ‘anti-correlation with’ to a less strong phrase ‘comparison with’ in the caption.\nCaption of Figure 1. …Global age occurrences of LIPs and their comparison with plate-speed1 and\nnumber of orogens7 through time…\n89-91: References are needed for this sentence.\nReply: Thanks. A key reference is added (Ref.6). In addition, a few references (Refs. 2-6) are added in\nthe relevant part in ‘Method’.\nLns 95-109: We think that it needs to be made explicit why you are choosing to exclude LIPs associated\nwith Gondwana assembly.\nReply: Thanks. This paragraph is shortened (cut 60 words) and moved into discussion.\nLines 150-160: Figure 3 also shows that the LIPs immediately following the breakup show primitive to\nenriched compositions; while those right prior to breakup show a wide range from very enriched to\nminor depleted . This increase of enrichment following breakup but come back to depletion prior to\nnext cycle of breakup could be originated from primitive sources (e.g., Central Iapetus30) or continental\nlithosphere (e.g., Volyn31) at the drifting stage after breakup, followed by involvement of both\nsubduction system and continental lithosphere during assembly (e.g., Emeishan32). Multiple models\nsuggest a protracted breakup of the Rodinia23,24; however, the 700500 Ma LIPs show features of\nprimitive sources (e.g., Central Iapetus30) or continental (Volyn31) and they were not likely related to\nbreakup but rather continuous drifting, being ‘weakened’ with less depleted source. This is one reason\nto limit the breakup of Rodinia to 940–720 Ma, and to propose the 720 Ma Franklin as the ‘terminal’\nplume (Fig. 3).\nLns 330-342: Thank you for including both approaches to defining the LLVP boundaries based on LIP\neruptions and including some reasoning for choosing one over another. We think the descriptions of\nthe distinctions between the two approaches could be a bit clearer, there are a lot of words being used\nin an attempt to summarise the differences between the two approaches, eg. ‘restored’ ‘apparent’\n‘real time’ ‘contemporary’, but perhaps a slightly more in depth description would be helpful to the\nreader.\nReply: Thanks. The word ‘real-time’ is deleted. We added two lines (see below) to explain the meaning\nof the two approaches to make it clearer.\nLines 274-277: The former approach implies that the shape of new LLSVPs was formed right at the\ninitial breakup stage of supercontinents and responded to the assembly of them (‘top-down’); while\nthe later infers that their shape was not formed until the final breakup and thus responded the\ndispersal of the supercontinents (‘bottom-up’).\nMinor:\nLn 41: ‘hereafter’ rather than heretofore.\nReply: Thanks. Changed.\nFig. 4 - Some text is difficult to read.\nReply: Thanks. Reworded a few places.\nFigure 4 Caption: ……An ‘Incipient incipient plume’ is the earliest plume since assembly of a\nsupercontinent; while a ‘terminal plume’ is the latest during the breakup. It presumes that the\nreaching……Schematic cross-section of Earth on the bottom is sketched based on refs….\nResponses to other reviewers:\nWe would also like to emphasise our support for some of the points raised by other reviewers, in\nparticular:\nThe response to reviewer 1 about why you consider LIPs during breakup to be more significant that\nthose during assembly. It might be useful to justify this in the text.\nReply: Thanks. So we agree. A few sentences are added in the last paragraph.\nLines 286-290: In addition, we consider that LIPs formed during breakup are more important in\nconstraining the shape of LLSVPs as, 1) there were more LIPs and thus stronger LLSVPs during breakup\nthan assembly12,13; 2) the LLSVPs may be more dynamic and their shifting was more significant during\nassembly than breakup, while its replenishment must be on the contrary (Fig. 4).\nThe velocities plotted in Fig 1 are estimates for the velocities of the continents and you have noted\nthat as such in the figure caption, however is this really the correct measure to be using. Would global\nplate speed (inclusive of oceanic plates) be more appropriate?\nReply: Thanks. Yes, it is good to use velocities of global plates rather than only continents. Now in the\nrevision, we change to plot speed of the global plates after Ref. 1\nSee Figure 1c.\nReviewer #3 (Remarks to the Author):\nI co-reviewed this manuscript with one of the reviewers who provided the listed reports. This is part\nof the Nature Communications initiative to facilitate training in peer review and to provide appropriate\nrecognition for Early Career Researchers who co-review manuscripts.\nReply: Thanks.\nReviewer #4 (Remarks to the Author):\n2 / 3\nThanks to the review, the manuscripts better presents the replenishment of the LLSVP, and also\ndiscusses the difference between plumes from the breakup and plumes from the later stage evolution.\nThey show different eNd values, which was shown in figure 2 and explained in the manuscript.\nThe addition of these data, strengthen the current model presented by the authors.\nall my comments were addressed and thus, I have nothing less to say before acceptance.\nReply: Thanks.\nReferences\nFrontiers 15 (2024). https://doi.org:10.1016/j.gsf.2024.101922\n(1997). https://doi.org:10.1038/385219a0\nExperimental Data on Olivine, Pyroxene, and Feldspars. Geochemistry International 62, 221-233\n(2024). https://doi.org:10.1134/s0016702924030030\n(1987). https://doi.org:10.1130/0091-7613(1987)15<893:Uaaoca>2.0.Co;2\nGeosystems 5 (2004). https://doi.org:10.1029/2003gc000597\nchanging with time? Precambrian Research 259, 278-289 (2015).\nhttps://doi.org:10.1016/j.precamres.2014.07.015\nProc Natl Acad Sci U S A 111, 8735-8740 (2014). https://doi.org:10.1073/pnas.1318135111\n479-515 (2015).\nlarge low shear‐wave velocity provinces in the lower mantle. Geochemistry, Geophysics,\nGeosystems 17, 5056-5077 (2016). https://doi.org:10.1002/2016gc006605\nevolution of Earth's mantle and core. Geochemistry, Geophysics, Geosystems 16, 3400-3413\n(2015). https://doi.org:10.1002/2015gc005996\nsupercontinents: Toward completing the plate tectonic revolution. Lithos 174, 1-14 (2013).\nhttps://doi.org:10.1016/j.lithos.2013.02.017\nepisodes. Precambrian Research 323, 1-5 (2019). https://doi.org:10.1016/j.precamres.2019.01.009\n3 / 3"}]

Decision letter