Earth and Planetary Science

The Ironian Ocean and the 2.2–1.8 Ga Introversion Process in the Formation of the Columbia (Nuna) Supercontinent

Alexandre de Oliveira Chaves

Manoel Teixeira da Costa Research Center, Institute of Geosciences, Federal University of Minas Gerais, Belo Horizonte MG 31270-901, Brazil

DOI: https://doi.org/10.36956/eps.v4i2.2161

Received: 15 May 2025 | Revised: 11 June 2025 | Accepted: 27 June 2025 | Published Online: 8 July 2025

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Abstract

Robust evidence on the existence of the Columbia (Nuna) supercontinent's internal ocean—the Ironian Ocean (name proposed here for the first time)—has been compiled from scientific literature. Remnants of Superior-type banded iron formations suggest the 2.5–2.2 Ga ocean spreading stage, as well as eclogites, blueschists, oceanic plateau, eclogite xenolith and ophiolites point to 2.2–1.8 Ga ocean closure stage along its suture zone. The 2.10–1.95 Ga collisional orogens of the Columbia (Nuna) supercontinent would have been formed throughout impact of continental lithospheric fragments during the consumption of the Ironian internal ocean by introversion process developed in the formation of the Columbia (Nuna) in the Paleoproterozoic Earth. These collisional orogens are located along the suture zone of the Ironian ocean, in a situation that indicates the process of introversion. Although tectonic stress associated with the 1.9-1.8 Ga accretionary and intracontinental orogenies contributed complementarily to the assembly of Columbia (Nuna) around 1.75 Ga, this supercontinent formed essentially by collisional orogenesis during Ironian Ocean closure and therefore by introversion process.

Keywords: Columbia (Nuna) Supercontinent; Internal Ocean; Introversion; Ironian

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References

[1] Roberts, N.M.W., 2013. The boring billion? Lid tectonics, continental growth and environmental change associated with the Columbia supercontinent. Geoscience Frontiers. 4(6), 681–691.

[2] Nance, R.D., 2021. The Supercontinent Cycle. In: Alderton, D., Elias, S.A. (eds.). Encyclopedia of Geology, 2nd ed. Academic Press: Cambridge, UK. pp. 891–902.

[3] Li, Z.X., Mitchell, R.N., Spencer, C.J., et al., 2019. Decoding Earth’s rhythm: Modulation of supercontinent cycles by longer superocean episodes. Precambrian Research. 323, 1–5.

[4] Zhang, N., Dang, Z., Huang, C., et al., 2018. The dominant driving force for supercontinent breakup: Plume push or subduction retreat? Geoscience Frontiers. 9(4), 997–1007.

[5] Li, Z.X., Zhong, S., 2009. Supercontinent-superplume coupling, true polar wander and plume mobility: plate dominance in whole-mantle tectonics. Physics of the Earth and Planetary Interiors. 176(3–4), 143–156.

[6] Martin, E.L., Cawood, P.A., Murphy, B., et al., 2024. The tectonics of introversion and extroversion: redefining interior and exterior oceans in the supercontinent cycle. In: Nance, R.D., Strachan, R.A., Quesada, C., et al. (eds.). Supercontinents, Orogenesis and Magmatism. The Geological Society of London: London, UK. 542, pp. 15–29. DOI: https://doi.org/10.1144/SP542-2023-54

[7] Rogers, J.J.W., Santosh, M., 2002. Configuration of Columbia, a Mesoproterozoic supercontinent. Gondwana Research. 5(1), 5–22.

[8] Zhao, G., Sun, M., Wilde, S.A., et al., 2004. A Paleo-Mesoproterozoic supercontinent: Assembly, growth and breakup. Earth Science Reviews. 67(1–2), 91–123.

[9] Zhang, S., Li, Z.X., Evans, D.A.D., et al., 2012. Pre-Rodinia supercontinent Nuna shaping up: a global synthesis with new paleomagnetic results from North China. Earth and Planetary Science Letters. 353, 145–155.

[10] Pisarevsky, S.A., Elming, S.A., Pesonen, L.J., et al., 2014. Mesoproterozoic paleogeography: Supercontinent and beyond. Precambrian Research. 244, 207–225.

[11] Chaves, A.O., 2021. Columbia (Nuna) supercontinent with external subduction girdle and concentric accretionary, collisional and intracontinental orogens permeated by large igneous provinces and rifts. Precambrian Research. 352, 106017. DOI: https://doi.org/10.1016/j.precamres.2020.106017

[12] Li, Z.X., Liu, Y., Ernst, R., 2023. A dynamic 2000–540 Ma Earth history: From cratonic amalgamation to the age of supercontinent cycle. Earth-Science Reviews. 238, 104336. DOI: https://doi.org/10.1016/j.earscirev.2023.104336

[13] Zhao, G., Cawood, P.A., Wilde, S.A., et al., 2002. A review of the global 2.1–1.8 Ga orogens: implications for a pre-Rodinian supercontinent. Earth Science Reviews. 59(1–4), 125–162.

[14] Meert, J.G., 2012. What’s in a name? The Columbia (Palaeopangea/Nuna) Supercontinent. Gondwana Research. 21(4), 987–993.

[15] Gower, C.F., Ryan, A.B., Rivers, T., 1990. Mid-Proterozoic Laurentia-Baltica; an overview of its geological evolution and a summary of the contributions made by this volume. In: Gower, C.F., Rivers, T., Ryan, B. (eds.). Mid-Proterozoic Laurentia-Baltica. Geological Association of Canada: Newfoundland and Labrador, Canada. pp. 1–20.

[16] Rogers, J.J.W., 1996. A history of continents in the past three billion years. Journal of Geology. 104(1), 91–107.

[17] Kusky, T.M., Santosh, M., 2009. The Columbia connection in North China. In: Reddy, S.M., Mazumder, R., Evans, D., et al. (eds.). Paleoproterozoic Supercontinents and Global Evolution. The Geological Society of London: London, UK. pp. 49–71. DOI: https://doi.org/10.1144/SP323.3

[18] Palin, R.M., Santosh, M., Cao, W., et al., 2020. Secular metamorphic change and the onset of plate tectonics. Earth-Science Reviews. 207, 103172. DOI: https://doi.org/10.1016/j.earscirev.2020.103172

[19] Stern, R.J., 2023. The Orosirian (1800–2050 Ma) plate tectonic episode: Key for reconstructing the Proterozoic tectonic record. Geoscience Frontiers. 14(3), 101553. DOI: https://doi.org/10.1016/j.gsf.2023.101553

[20] Meert, J.G., Santosh, M., 2017. The Columbia supercontinent revisited. Gondwana Research. 50, 67–83.

[21] Betts, P.G., Giles, D., Schaefer, B.F., 2008. Comparing 1800–1600 Ma accretionary and basin processes in Australia and Laurentia: Possible geographic connections in Columbia. Precambrian Research. 166(1–4), 81–92.

[22] Betts, P.G., Armit, R.J., Stewart, J., et al., 2015. Australia and Nuna. Geological Society, London, Special Publications. 424(1), 47–81. DOI: https://doi.org/10.1144/sp424.2

[23] Xu, H., Yang, Z., Peng, P., et al., 2017. Magnetic fabrics and rock magnetism of the Xiong’er volcanic rocks and their implications for tectonic correlation of the North China Craton with other crustal blocks in the Nuna/Columbia supercontinent. Tectonophysics. 712, 415–425.

[24] Pesonen, L.J., Mertanen, S., Veikkolainen, T., 2012. Paleo-Mesoproterozoic Supercontinents – A paleomagnetic view. Geophysica. 48(1–2), 5–47.

[25] Ernst, R.E., 2014. Large Igneous Provinces. Cambridge University Press: Cambridge, UK. pp. 1–666.

[26] Pirajno, F., Hoatson, D.M., 2012. A review of Australia’s Large Igneous Provinces and associated mineral systems: implications for mantle dynamics through geological time. Ore Geology Reviews. 48, 2–54.

[27] Demirer, K., 2012. U-Pb baddeleyite ages from mafic dyke swarms in Dharwar craton, India – links to an ancient supercontinent [Master's thesis]. Lund University: Lund, Sweden. pp. 1–25.

[28] Reis, N.J., Teixeira, W., Hamilton, M.A., et al., 2013. Avanavero mafic magmatism, a late Paleoproterozoic LIP in the Guiana Shield, Amazonian Craton: U-Pb TIMS baddeleyite, geochemical and paleomagnetic evidence. Lithos. 174, 175–195.

[29] Peng, P., 2010. Reconstruction and interpretation of the giant mafic dyke swarms: a case study of 1.78 Ga magmatism in the North China Craton. In: Kusky, T.M., Zhai, M.-G., Xiao, W. (eds.). The Evolving Continents: Understanding Processes of Continental Growth. Geological Society of London: London, UK. pp. 163–178. DOI: https://doi.org/10.1144/SP338.8

[30] Cederberg, J., Soderlund, U., Oliveira, E.P., et al., 2016. U-Pb baddeleyite dating of the Proterozoic Para de Minas dyke swarm in the Sao Francisco craton (Brazil)-implications for tectonic correlations with Siberia, Congo and North China cratons. GFF. 138(1), 219–240. DOI: https://doi.org/10.1080/11035897.2015.1093543

[31] Teixeira, W., D'Agrella-Filho, M.S., Hamilton, M.A., et al., 2013. U-Pb (ID-TIMS) baddeleyite ages and paleomagnetism of 1.79 and 1.59 Ga tholeiitic dyke swarms, and the position of the Rio de la Plata craton within the Columbia supercontinent. Lithos. 174, 57–174.

[32] Bogdanova, S.V., Gintov, O.B., Kurlovich, D.M., et al., 2013. Late Palaeoproterozoic mafic dyking in the Ukranian Shield of Volgo-Sarmatia caused by rotation during the assembly of supercontinent Columbia (Nuna). Lithos. 174, 196–216.

[33] Pisarevsky, S.A., Bylund, G., 2010. Paleomagnetism of the 1780–1770 Ma mafic and composite intrusions of the Smaland (Sweden): implications for the Mesoproterozoic supercontinent. American Journal of Science. 310(9), 1168–1186.

[34] Baratoux, L., Soderlund, U., Ernst, R.E., et al., 2018. New U-Pb baddeleyite ages of mafic dyke swarms of the West African and Amazonian Cratons: implication for their configuration in supercontinentes through time. In: Srivastava, R.K., Ernst, R.E., Peng, P. (eds.). Dyke Swarms of the World – A Modern Perspective. Springer: Singapore. pp. 263–314.

[35] Gladkochub, D.P., Pisarevsky, S.A., Donskaya, T.V., et al., 2010. Proterozoic mafic magmatism in Siberian craton: An overview and implications for paleocontinental reconstruction. Precambrian Research. 183(3), 660–668.

[36] Shankar, R., Vijayagopal, B., Kumar, A., 2014. Precise Pb–Pb baddeleyite ages of 1765 Ma for a Singhbhum ‘newer dolerite’ dyke swarm. Current Science. 106(9), 1306–1310.

[37] Ernst, R.E., Bleeker, W., Soderlund, U., et al., 2013. Large Igneous Provinces and supercontinents: toward completing the plate tectonic revolution. Lithos. 174, 1–14.

[38] Chaves, A.O., Rezende, C.R., 2019. Fragments of 1.79-1.75 Ga Large Igneous Provinces in reconstructing Columbia (Nuna): a Statherian supercontinent-superplume coupling? Episodes, Journal of Internacional Geoscience. 42(1), 55–67. DOI: https://doi.org/10.18814/epiiugs/2019/019006

[39] Youbi, N., Kouyate, D., Soderlund, U., et al., 2013. The 1750 Ma Magmatic Event of the West African Craton (Anti-Atlas, Morocco). Precambrian Research. 236, 106–123.

[40] Salminen, J., Klein, R., Mertanen, S., 2019. New rock magnetic and paleomagnetic results for the 1.64 Ga Suomenniemi dyke swarm, SE Finland. Precambrian Research. 329, 195–210.

[41] Klausen, M.B., Nilsson, M.K.M., 2019. The Melville Bugt Dyke Swarm across SE Greenland: A closer link to Mesoproterozoic AMCG-complexes. Precambrian Research. 329, 88–107.

[42] Kouyate, D., Soderlund, U., Youbi, N., et al., 2013. U-Pb baddeleyite and zircon ages of 2040 Ma, 1650 Ma and 885 Ma on dolerites in the West African Craton (Anti-Atlas inliers): Possible links to break-up of Precambrian supercontinents. Lithos. 174, 71–84.

[43] Metelkin, D.V., Ernst, R.E., Hamilton, M.A., 2011. A ca. 1640 Ma mafic magmatic event in southern Siberia, and links with northern Laurentia. Geological Society of America. 43, 268.

[44] Cai, Y., Pei, J., Zhang, S.H., et al., 2020. New paleomagnetic results from the ca. 1.68–1.63 Ga mafic dyke swarms in Western Shandong Province, Eastern China: Implications for the reconstruction of the Columbia supercontinent. Precambrian Research. 337, 105531. DOI: https://doi.org/10.1016/j.precamres.2019.105531

[45] Silveira, E.M., Soderlund, U., Oliveira, E.P., et al., 2013. First precise U–Pb baddeleyite ages of 1500 Ma mafic dykes from the Sao Francisco Craton, Brazil, and tectonic implications. Lithos. 174, 144–156.

[46] Ernst, R.E., Youbi, N., 2017. How large igneous provinces affect global climate, sometimes cause mass extinctions, and represent natural markers in the geological record. Palaeogeography, Palaeoclimatology, Palaeoecology. 478, 30–52. DOI: https://doi.org/10.1016/j.palaeo.2017.03.014

[47] Ernst, R.E., Okrugin, A.V., Veselovskiy, R.V., et al., 2016. The 1501 Ma Kuonamka Large Igneous Province of northern Siberia: U-Pb geochronology, geochemistry, and links with coeval magmatism on other crustal blocks. Russian Geology and Geophysics. 57(5), 653–671.

[48] Peng, P., 2015. Precambrian mafic dyke swarms in the North China Craton and their geological implications. Science China Earth Sciences. 58(5), 649–675.

[49] El Bahat, A., Ikenne, M., Soderlund, U., et al., 2013. U-Pb ages and geochemistry of dolerite dykes in the Bas Draa Inlier of the Anti-Atlas of Morocco: newly identified 1380 Ma event in the West African Craton. Lithos. 174, 85–98.

[50] Cawood, P.A., Kroner, A., Collins, W.J., et al., 2009. Accretionary orogens through earth history. In: Cawood, P.A., Kroner, A. (eds.). Earth Accretionary Systems in Space and Time. Geological Society of London: London, UK. pp. 1–36. DOI: https://doi.org/10.1144/SP318.1

[51] Condie, K.C., 2013. Preservation and recycling of crust during accretionary and collisional phases of proterozoic orogens: a bumpy road from Nuna to Rodinia. Geosciences. 3(2), 240–261.

[52] Stauffer, M.R., 1984. Manikewan: An early proterozoic ocean in central Canada, its igneous history and orogenic closure. Precambrian Research. 25(1–3), 257–281.

[53] Wang, C.L., Zhang, L.C., Dai, Y.P., et al., 2015. Geochronological and geochemical constraints on the origin of clastic meta-sedimentary rocks associated with the Yuanjiacun BIF from the Lüliang Complex, North China. Lithos. 212, 231–246.

[54] Pickard, A.L., 2003. SHRIMP U–Pb zircon ages for the Palaeoproterozoic Kuruman Iron Formation, Northern Cape Province, South Africa: evidence for simultaneous BIF deposition on Kaapvaal and Pilbara Cratons. Precambrian Research. 125(3–4), 275–315.

[55] Ganno, S., Njiosseu, T.E.L., Kouankap, N.G.D., et al., 2017. A mixed seawater and hydrothermal origin of superior-type banded iron formation (BIF)-hosted Kouambo iron deposit, Palaeoproterozoic Nyong series, Southwestern Cameroon: Constraints from petrography and geochemistry. Ore Geology Reviews. 80, 860–875.

[56] Rosière, C.A., Spier, C.A., Rios, F.J., et al., 2008. The itabirites of the Quadrilátero Ferrífero and related high-grade iron ore deposits: an overview. Reviews in Economic Geology. 15, 223–254.

[57] Feybesse, J.L., Billa, M., Guerrot, C., et al., 2006. The paleoproterozoic Ghanaian province: geodynamic model and ore controls, including regional stress modeling. Precambrian Research. 149(3–4), 149–196.

[58] Bettucci, L.S., Peel, E., Oyhantçabal, P., 2009. Precambrian geotectonic units of the Río de La Plata craton. International Geology Review. 52(1), 32–50.

[59] Savko, K.A., Samsonov, A.V., Kholin, V.M., et al., 2017. The Sarmatia megablock as a fragment of the Vaalbara supercontinent: Correlation of geological events at the Archean‒Paleoproterozoic transition. Stratigraphy and Geological Correlation. 25, 123–145.

[60] Sims, P.K., Carter, L.M.H., 1993. Archean and Proterozoic geology of the Lake Superior region, U.S.A., 1993. US Government Printing Office: Washington, DC, USA. DOI: https://doi.org/10.3133/pp1556

[61] Ganne, J., Andrade, V., Weinberg, R.F., et al., 2012. Modern-style plate subduction preserved in the Palaeoproterozoic West African craton. Nature Geoscience. 5(1), 60–65.

[62] Chaves, A.O., 2024. 2.13 Ga Lawsonite/Barroisite-Bearing E-MORB Signature Metagabbro Associated with Spinel Meta-peridotite from Itaguara (São Francisco Craton, Brazil): Oldest Blueschist-Facies Fragment of Oceanic Moho? Earth and Planetary Science. 3(2), 14–40.

[63] Chaves, A.O., Porcher, C.C., 2020. Petrology, geochemistry and Sm-Nd systematics of the Paleoproterozoic Itaguara retroeclogite from São Francisco/Congo Craton: one of the oldest records of the modern-style plate tectonics. Gondwana Research. 87, 224–237.

[64] Möller, A., Appel, P., Mezger, K., et al., 1995. Evidence for a 2 Ga subduction zone: Eclogites in the Usagaran belt of Tanzania. Geology. 23(12), 1067–1070.

[65] François, C., Debaille, V., Paquette, J.L., et al., 2018. The earliest evidence for modern-style plate tectonics recorded by HP–LT metamorphism in the Paleoproterozoic of the Democratic Republic of the Congo. Scientific Reports. 8(1), 15452. DOI: https://doi.org/10.1038/s41598-018-33823-y

[66] Loose, D., Schenk, V., 2018. 2.09 Ga old eclogites in the Eburnian-Transamazonian orogen of southern Cameroon: significance for Palaeoproterozoic plate tectonics. Precambrian Research. 304, 1–11.

[67] Bouyo, M.H., Penaye, J., Mouri, H., et al., 2019. Eclogite facies metabasites from the Paleoproterozoic Nyong Group, SW Cameroon: Mineralogical evidence and implications for a high-pressure metamorphism related to a subduction zone at the NW margin of the Archean Congo Craton. Journal of African Earth Sciences. 149, 215–234.

[68] Weller, O., St-Onge, M., 2017. Record of modern-style plate tectonics in the Palaeoproterozoic Trans-Hudson orogen. Nature Geoscience. 10(4), 305–311. DOI: https://doi.org/10.1038/ngeo2904

[69] Müller, S., Dziggel, A., Kolb, J., et al., 2018. Mineral textural evolution and PT-path of relict eclogite-facies rocks in the Paleoproterozoic Nagssugtoqidian Orogen, South-East Greenland. Lithos. 296, 212–232.

[70] Zhao, G., Cawood, P.A., Wilde, S.A., et al., 2001. High-pressure granulites (retrograded eclogites) from the Hengshan Complex, North China Craton: petrology and tectonic implications. Journal of Petrology. 42(6), 1141–1170.

[71] Wan, B., Windley, B.F., Xiao, W., et al., 2015. Paleoproterozoic high-pressure metamorphism in the northern North China Craton and implications for the Nuna supercontinent. Nature Communications. 6(1), 8344. DOI: https://doi.org/10.1038/ncomms9344

[72] Yu, H.L., Zhang, L.F., Wei, C.J., et al., 2017. Age and P-T conditions of the Gridino-type eclogite in the Belomorian Province, Russia. Journal of Metamorphic Geology. 35(8), 855–869.

[73] Pirajno, F., 2004. Oceanic plateau accretion onto the north-western margin of the Yilgarn Craton, Western Australia: Implications for a mantle plume event at ca. 2.0 Ga. Journal of Geodynamics. 37(2), 205–231.

[74] Xu, C., Kynický, J., Song, W., et al., 2018. Cold deep subduction recorded by remnants of a Paleoproterozoic carbonated slab. Nature Communications. 9(1), 2790. DOI: https://doi.org/10.1038/s41467-018-05140-5

[75] Kontinen, A., 1987. An early Proterozoic ophiolite - The Jormua mafic-ultramafic complex, Northeastern Finland. Precambrian Research. 35, 313–341.

[76] Scott, D., Helmstaedt, H., Bickle, M., 1992. Purtuniq ophiolite, Cape Smith belt, northern Quebec, Canada: A reconstructed section of Early Proterozoic oceanic crust. Geology. 20(2), 173–176.

[77] Bekker, A., Slack, J.F., Planavsky, N., et al., 2010. Iron formation: the sedimentary product of a complex interplay among mantle, tectonic, oceanic, and biospheric processes. Economic Geology. 105(3), 467–508.

[78] Wan, B., Yang, X., Tian, X., et al., 2020. Seismological evidence for the earliest global subduction network at 2 Ga ago. Science Advances. 6(24), eabc5491. DOI: https://doi.org/10.1126/sciadv.abc5491

[79] Chatterjee, S., Mukherjee, S., 2022. Overview on GPlates: Focus on plate reconstruction. Turkish Journal of Earth Sciences. 31(2), 113–136.

[80] Dash, S., Babu, E.V.S.S.K., Ganne, J., et al., 2025. Plate tectonics through Earth’s history: Constraints from the thermal evolution of Earth’s upper mantle. International Geology Review. 67(4), 500–533.

[81] Müller, R.D., Cannon, J., Qin, X., et al., 2018. GPlates: Building a virtual Earth through deep time. Geochemistry, Geophysics, Geosystems. 19(7), 2243–2261.