The Sturtian Snowball Earth cryochron (ca. 717–660 Ma) was the Earth’s longest glaciation, yet mechanisms for its persistence remain debated. We report high‑precision ID‑TIMS baddeleyite U–Pb ages of 700.6 ± 9.5 Ma and 694.0 ± 2.0 Ma for the Olumi dolerite dyke swarm (Gabon) and Sumbi dolerite sills (DRC), defining a previously unrecognized ca. 700–694 Ma Olumi–Sumbi large igneous province (LIP). Paleomagnetic constraints for the Olumi dyke indicate low‑latitude emplacement, placing the Congo Craton near the equator. Together with the ca. 719 Ma Franklin LIP, these tropical LIPs may have contributed to both initiating and sustaining the Sturtian glaciation. Episodic magmatism might have driven transient warming and deglaciation via volcanic CO2 emissions, followed by efficient chemical weathering of fresh mafic rocks, which enhanced CO2 drawdown and restored global ice cover. This suggests that tropical emplacement of LIPs during the Sturtian Snowball Earth cryochron might have strongly impacted the dynamics of the Earth’s longest glaciation. “Previously unrecognized ca. 700–694 Ma Olumi–Sumbi large igneous province with low‑latitude emplacement may have contributed to both initiating and sustaining Earth's longest glaciation, the Sturtian glaciation, shown using baddeleyite uranium-lead ages and paleomagnetic constraints.”

A new U–Pb ID–TIMS baddeleyite date of 2252.4 ± 5.5 Ma is obtained for an ENE-trending mafic dyke in the central-western Bastar craton that signifies its link with the ca. 2.25 Ga Chhura dyke swarm within the craton. This suggests that the ca. 2.25 Ga magmatic event is more widely distributed across the Bastar craton, despite its comparatively low dyke density. The studied dykes exhibit evolved basaltic compositions with restricted major- and trace-element variability. Geochemical systematics indicate that magma differentiation was governed by fractional crystallization, involving early olivine ± clinopyroxene removal followed by plagioclase-dominated crystallization within transient crustal magma reservoirs. The absence of systematic variation in contamination-sensitive trace-element ratios indicates negligible crustal assimilation. Instead, arc-like trace-element characteristics, including LILE enrichment and Nb–Ta–Ti depletion, are consistent with moderate degree of partial melting (10–15%) of a spinel-rich subcontinental lithospheric mantle source previously metasomatised by slab-derived fluids during Archean subduction. Comparison with coeval 2.26–2.25 Ga dyke swarms of the Dharwar and Singhbhum cratons reveals strong geochemical coherence, with subtle spatial variation in plume–lithosphere interaction. Anisotropy of magnetic susceptibility (AMS) data, supported by shape-preferred orientation (SPO) analyses and reported here for the first time from Bastar mafic dykes, record sub-horizontal to moderately inclined K1 axes, indicating lateral magma transport within ENE-trending fractures. Imbricated fabrics consistently indicate southwest-directed magma flow, suggesting a plume centre northeast of the Bastar craton. Integration of geochemical and structural constraints supports a two-stage geodynamic model in which plume-related thermal perturbation triggered melting of previously subduction-modified lithospheric mantle.

A NNW-trending mafic dyke from the central-western Bastar craton yields a U-Pb ID-TIMS baddeleyite age of 1944 +/- 6 Ma. By correlating additional dykes with similar trend and geochemical characteristics, we identify a previously unrecognized dyke swarm, named herein the Pakhanjore swarm. Geochemical evidence suggests that the studied rocks are derived from partial melting of a spinel-rich, shallow lithospheric mantle source, involving 5-15 % partial melting as indicated by the non-modal batch melting model. AFC (Assimilation and fractional crystallization) modelling further reveals that fractional crystallization with moderate crustal assimilation (r = 0.3) contributes to the overall magmatic evolution. The similarity in trend of the ca. 1.94 Ga Pakhanjore swarm with the 1.89-1.88 Ga Bastanar swarm, and the ca. 1.85 Ga Sonakhan swarm of the Bastar craton suggests their emplacement occurred within a shared tectonic regime and/or paleostress field. Although notable geochemical similarities exist between the ca. 1.94 Ga Pakhanjore swarm and the 1.89-1.88 Ga and ca. 1.85 Ga mafic dykes, a direct genetic linkage remains inconclusive. However, based on available geological, geochronological, and geochemical data, the 1.89-1.88 Ga and ca. 1.85 Ga swarms appear to be part of a shared LIP event, whereas the ca. 1.94 Ga event likely represents an independent magmatic episode. The spatial alignment of all three dyke swarms with the NNW-trending Pranhita-Godavari Basin suggests a potential tectonic connection.

Large igneous provinces (LIPs) are excellent spatial and temporal geological recorders. However, our understanding of LIPs is hindered by a lack of preservation and alteration of many LIPs through deep time. Several LIPs have been emplaced in the Rhyacian. These LIPs demonstrate a connection across the Superior, Wyoming and North Atlantic cratons. In this study we use new U-Pb ID-TIMS baddeleyite geochronology, petrography, geochemistry, paleomagnetic and rock magnetic data on mafic intrusions to show that the Kaapvaal Craton in southern Africa was possibly a part of this 'clan of cratons'. New ages come from the Buffalo River Gorge Dyke Swarm on the south-easternmost region of the craton, dated herein at 2165 +/- 6 Ma and 2163 +/- 3 Ma. A younger 2148 +/- 3 Ma dyke was also identified in the region. These dykes invite comparison to magmatic units within the upper Transvaal Supergroup, including the Hekpoort Formation basaltic andesites and the Machadodorp Member basalts, together with the Mashishing Dyke Swarm and various sills, with at least the Hekpoort recognised as a LIP in the ca. 2.22-2.14 Ga time frame. However, this new magmatic event is close in age to a reported ca. 2.16-2.14 Ga metamorphic event within the Transvaal Supergroup. In addition, a new Rhyacian magmatic barcode record for the Kaapvaal Craton is presented that can be compared with coeval LIPs in the Superior, Wyoming and North Atlantic cratons. We suggest that the Kaapvaal Craton was likely a near neighbour to these cratonic blocks at ca. 2.16-2.15 Ga when combining the new magmatic barcode record with a new tentative virtual geomagnetic pole at -57.4 degrees N, 9.1 degrees E (dp/dm of 20.2/22.9).

The Amazonian Craton is host to one of Earth's largest Proterozoic silicic large igneous provinces (SLIPs), the Orocaima SLIP (ca. 1.98 Ga). Nevertheless, the mechanism(s) responsible for this large-flux felsic magmatic event and its relationships with regional tectonics and/or mantle processes remain debated. New geochronologic and geochemical results from multiple mafic dike swarms in the Amazonian Craton, namely the Guaniamo, Rio Aro, El Manteco-Supamo, and Goboy swarms, reveal a close temporal, spatial, and geochemical association with the Orocaima SLIP. The radiating arrangement of these swarms spanning 90 degrees of arc, their strongly tholeiitic geochemical affinity, and their short-lived emplacement ca. 1.98 Ga including in regions far from any inferred subducting plate margins all strongly suggest: (1) an intraplate, plume-related origin, and (2) a radiating arrangement defining a plume center located at similar to 2.5 degrees N, 61.2 degrees W, near the SW margin of proto-Amazonia at the time and coinciding with the location of the Takutu graben. Discovery of this previously unrecognized radiating swarm array, herein grouped within a proposed Yanomami large igneous province, and its close spatial and temporal association with the Orocaima SLIP suggests a plume-triggered origin for SLIP development, thus arguing against accretionary models for the origin of the Orocaima silicic magmatic belt.

The Varena Iron Ore deposit in the SW East European Craton is a significant ore body that occurs within metamorphosed and hydrothermally reworked Paleoproterozoic dolostones. We have performed microstructural investigations supplemented with mineral chemistry and geochronological investigations (LA-ICP-MS) to obtain age constraints on the ore-forming event(s) and improve the understanding of the conditions during mineralization process. Mineral chemistry and textures suggest a drop in pressure after the event of peak metamorphic skarn formation. Influx of oxidized, iron-rich H2O 2 O fluids resulted in (1) Mg mobility that caused secondary dolomitization of calcite, (2) dissolution of metamorphic magnetite and formation of a new, inclusion-rich (Mag1) and inclusion-poor (Mag-2) magnetite, and (3) replacement of the peak skarn assemblages. During these fluid- related processes, accessory phases of monazite, baddeleyite, and zircon were formed. Their U-Pb - Pb dating yield individually robust ages of 1721 f 9 Ma (monazite, 23 spots), 1703 f 10 Ma (baddeleyite, 18 spots) and 1706 f 54 Ma (zircon, 14 spots), respectively. The weighted mean age of 1713 f 7 Ma (2 sigma internal) is considered to represent the best age estimate of the iron-ore mineralization in the Varena Iron Ore deposit, and possibly also dates influx of P, REEs etc. into the system. This mineralization event is contemporaneous with ca. 1.73-1.70 Ga metamorphic reworking of the host rocks in the region and may be linked to regional continental-margin type Transscandinavian Igneous Belt (TIB) magmatism in south-central Sweden.

Plate tectonics is a unique feature of Earth, but its proposed time of initiation is still controversial, with published estimates ranging from ca. 4.2 to 0.7 Ga. Paleomagnetic data can provide a robust argument for one essential aspect of plate tectonics: large-scale relative lateral motions of distinct, rigid crustal blocks. Previously, the oldest relative horizontal motion between two or more blocks was constrained to a broad age interval of ca. 2.7-2.17 Ga using paleomagnetic data. In this study, we obtain a robust ca. 2.48 Ga paleomagnetic pole from Wyoming craton. Combining this result with the ca. 2.7-2.17 Ga apparent polar wander paths from Wyoming and Superior cratons, we suggest that they assembled during ca. 2.7-2.5 Ga and remained directly juxtaposed until ca. 2.17 Ga. Tectonostratigraphic data and geological proxies also suggest Wyoming and Superior collided at ca. 2.6 Ga. The results provide strong evidence for relative horizontal motion between crustal blocks during the Neoarchean. Together with other tectonic proxies, the data suggest plate mobilism in operation prior to 2.5 Ga.

While whole-rock Lu-Hf isotope analysis remains one of the only ways to obtain initial Hf isotope signatures of old mafic rocks, Hf isotope analyses of more robust accessory zircon in intermediate to silicic rocks have largely replaced whole-rock analyses during the last decade. This has led to a discrepancy in the amount of existing data from mafic and felsic lithologies. However, especially in mafic, Si-poor rocks with a metamorphic imprint, Hf isotope data rely on whole-rock analysis since baddeleyite, commonly used for U-Pb age analyses of mafic rocks, is sensitive to alteration and metamorphism. Hence, to accurately evaluate the trace element and isotope sig-natures of altered mafic rocks, it is important to understand the mechanisms of element mobility during meta-morphism. Here, we report whole-rock trace element compositions, Lu-Hf and Sm-Nd isotope data from variably deformed and metamorphosed samples of a mafic intrusion in southern Sweden, the & ANGS;ker metabasite. These data suggest that trace elements were undisturbed on a whole-rock sample scale during deformation at upper amphibolite facies (at least 1000 MPa and 600 degrees C) metamorphism under hydrated conditions. Despite redistri-bution of Zr associated with the breakdown of baddeleyite and other igneous phases, the & ANGS;ker metabasite has retained its chemical and isotopic integrity since igneous crystallisation at ca. 1565 Ma. This study demonstrates and strengthens the feasibility of whole-rock analyses of (meta-)mafic rocks for determining initial 8Nd and 8Hf values, despite deformation and metamorphism under hydrated amphibolite-grade metamorphic conditions. Testing the coherence of the calculated initial Nd and Hf isotope ratios by examining variably deformed and metamorphosed varieties of a rock in a single outcrop, could be used as a model for research on more complex Archean rocks.

Widespread 720 Ma magmatism has been linked with the break-up of Rodinia and the onset of the Sturtian 'Snowball Earth' event. We report a new U-Pb baddeleyite age from the Baikal dyke subswarm in southern Siberia which increases the known extent of the 720 Ma Irkutsk LIP and confirms a previous hypothesis that the Baikal and Sayan subswarms converge at the southern tip of the Irkutsk promontory. Together they define a mantle plume centre with direct links to the 720 Ma Franklin plume centre of northern Laurentia, thus constraining the paleo-reconstruction of southern Siberia and northern Laurentia. It is inferred that this combined 720 Franklin - Irktusk LIP event is associated with the breakup of southern Siberia from northern Laurentia during fragmentation of the Rodinia supercontinent. Expansion of 720 Ma magmatism into Siberia greatly increases the scale of the Franklin-Irktusk LIP.

Abstract The Rodinia supercontinent broke apart during the Neoproterozoic. Rodinia break-up is associated with widespread intraplate magmatism on many cratons, including the c. 720–719 Ma Franklin large igneous province (LIP) of Laurentia. Coeval magmatism has also been identified recently in Siberia and South China. This extensive magmatism terminates ∼1 myr before the onset of the Sturtian Snowball Earth. However, LIP-scale magmatism and global glaciation are probably related. U–Pb isotope dilution–thermal ionization mass spectrometry (ID-TIMS) baddeleyite dating herein identifies remnants of a new c. 724–712 Ma LIP on the eastern Kalahari Craton in southern Africa and East Antarctica: the combined Mutare–Fingeren Dyke Swarm. This dyke swarm occurs in northeastern Zimbabwe (Mutare Dyke Swarm) and western Dronning Maud Land (Fingeren Dyke Swarm). It has incompatible element-enriched mid-ocean ridge basalt-like geochemistry, suggesting an asthenospheric mantle source for the LIP. The Mutare–Fingeren LIP probably formed during rifting. This rifting would have occurred almost ∼100 myr earlier than previous estimates in eastern Kalahari. The placement of Kalahari against southeastern Laurentia in Rodinia is also questioned. Proposed alternatives, invoking linking terranes between Kalahari and southwestern Laurentia or close to northwestern Laurentia, also present challenges with no discernible resolution. Nevertheless, LIP-scale magmatism being responsible for the Sturtian Snowball Earth significantly increases.

Table S8 — U-Pb ID-TIMS geochronology of baddeleyite at the University of Toronto

A new 130 to 140 Ma mafic dyke swarm, is identified in western South Africa. It consists of the previously undated Cederberg dyke swarm (CDS), for which we report U-Pb ID-TIMS baddeleyite ages of 131.4 +/- 4.5 Ma (Knersvlake subswarm) and 133.0 +/- 1.5 Ma (Doring-Tanqua subswarm). 40Ar/39Ar dates on these two samples and two additional dates of the Doring - Tanqua subswarm cluster between 128.5 +/- 1.4 Ma and 132.2 +/- 1.5 Ma. We also report 40Ar/39Ar ages of 139.3 +/- 3.5 Ma for an east-west trending dyke located further north: 27 km south of Kleinsee, and 140.3 +/- 1.2 Ma for an east-west dyke near Garies. Together, these eight ages robustly date the emplacement of the northern part of a Greater Cederberg- False Bay Dyke Swarm (GCFDS) at ca. 130 to 140 Ma. Trace and rare earth element datareported herein suggest these dykes are compositionally E-MORB basalts that underwent modification either via subduction-modified lithospheric mantle, or by continental crust, or a combination thereof, and are petrogenetically similar to the ca. 132 Ma False Bay dykes around Cape Town. Therefore, we propose to unify all these coeval and compositionally similar dykes into one large igneous province (LIP) termed the Greater Cederberg-False Bay Large Igneous Province (GCF-LIP).

Table S1 — Major, minor- and accessory minerals in the studied samples

Within the Anabar shield in the northern part of the Siberia, Late Precambrian mafic igneous units are widespread, which form dyke swarms of different ages of different trends. This paper presents new data on the composition, structure and U-Pb dating of the E-W trending Kengede dyke swarm. Three new U-Pb ID-TIMS baddeleyite ages (1496±7, 1494±3 and 1494±5 Ma) were obtained from three dykes, indicating that the Kengede swarm is part of the 1500 Ma Kuonamka large igneous province (LIP). The previously recognized Kuonamka Large Igneous Province (LIP) extends for 700 km from the Anabar shield to the Olenek uplift in the northern part of the Siberia and is potentially linked to coeval dykes and sills of the São Francisco craton and the Congo craton. The newly dated Kengede swarm is parallel to but offset by 50 km from the previously dated 1501±3 Ma Kuonamka swarm, and the identification of these two subparallel dyke subswarms of the Kuonamka LIP supports the earlier interpretation that mantle plume centre was located along the extrapolated trend of the dykes near the eastern or western margin of the Siberia. The paper examines features of sulfide Cu-Ni mineralization in dolerites of the Kengede and East Anabar dyke swarms and discusses potential Cu-Ni-sulfide mineralization linked to the Precambrian mafic dyke swarms of different ages in the north-east of the Siberia.

The Varena Iron Ore deposit In the SW East European Craton is situated in the metamorphosed and hydrothermally reworked Palaeproterozoic dolostones. A detail microstructural study supplemented with isotopic investigations allowed for dating of ore-forming events.

Abstract We propose a Precambrian megacraton (consisting of two or more ancient cratons), DHABASI in the Indian Shield, which includes the Dharwar, Bastar and Singhbhum cratons. This interpretation is mainly based on seven large igneous provinces (LIPs) that are identified in these three cratons over the age range of c. 3.35–1.77 Ga, a period of at least 1.6 Ga. The absence of any subsequent break-up of DHABASI since 1.77 Ga suggests that this megacraton has existed for the past 3.35 Ga. In addition to their use in recognizing this megacraton, these LIP events may also provide likely targets for Cu–Ni–Cr–Co–platinum group element deposits. We suggest that the megacraton DHABASI was an integral part of supercontinents/supercratons through Earth's history, and that it should be utilized as a distinct building block for palaeocontinental reconstructions rather than using the individual Dharwar, Bastar and Singhbhum cratons.