Abstract
The Imini mining district (southern foreland of the intraplate Atlasic belt of Morocco) hosts the largest Mn resources of North Africa, consisting of two laterally extensive bodies of high-grade pyrolusite-rich manganese ore and a third discontinuous medium-grade coronadite-rich Mn ore in a ~ 10–15-m-thick Cenomanian–Turonian dolostone unit. Until now, the origin and timing of the Mn ore have been poorly constrained. New Pb isotopic ratios show that Triassic series (basalts and ferruginous sandstone) are likely the source of the metals. 40Ar/39Ar dating of K-Mn oxides shows that the Mn-rich orebodies formed during at least three periods: late Cretaceous to late Paleocene (> 58 Ma), late Eocene (ca. 36.3 Ma), and early Burdigalian to early Serravalian probably in two pulses at ca. 19–20 Ma and ca. 13 Ma. These periods coincide with three known building phases of the Atlasic relief during late Cretaceous, late Eocene, and the Early(?)-Middle Miocene. We therefore propose the Atlasic tectonics as the first-order control of the Mn mineralization. Periods with regionally high elevations modified the climate to wetter conditions that supplied meteoric water to feed temporary aquifers. Relief building created the required hydraulic head to sustain (1) fluid-rock interaction between O2-poor acidic fluids and the Triassic series, (2) migration of the metal-rich fluid, and (3) to overpressure fluid in the Imini depositional site. The decreasing thickness of Triassic series in front of the Imini anticline forced these low-temperature (< 100 °C) fluids to mix with oxygenated and alkaline ground waters in the karst system and precipitate Mn oxides. The N70°-oriented Atlasic tectonic structure controls the orientation of the Mn deposits. The late Eocene–Early/Middle Miocene uplifts generated additional supplies and/or in situ remobilization of the primary late Cretaceous medium-grade ore to form the high-grade pyrolusite-rich ore.
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References
Algouti A, Algouti A, Taj-Eddine K (1999) Le Sénonien du Haut Atlas occidental, Maroc: sédimentologie, analyse séquentielle et paléogéographie. J Afr Earth Sc 29:643–658. https://doi.org/10.1016/S0899-5362(99)00121-9
Amouri M, Bouaziz S, Ennifar S et al (1991) Le gîte manganésifère du Jebel Aziza (Chaine des Chotts): étude de la minéralisation dans son cadre morphostructural et paléogéographique. Notes Du Service Géologique De Tunisie 58:133–150
Barbarand J, Bour I, Pagel M et al (2018) Post-Paleozoic evolution of the northern Ardenne Massif constrained by apatite fission-track thermochronology and geological data. BSGF - Earth Sci Bull 189:16. https://doi.org/10.1051/bsgf/2018015
Beaudoin B, Lesavre A, Pelissonnier H (1976) Action des eaux superficielles dans le gisement de manganese d’Imini (Maroc). Bulletin De La Société Géologique De France 18:95–100. https://doi.org/10.2113/gssgfbull.S7-XVIII.1.95
Beauvais A, Bonnet NJ, Chardon D et al (2016) Very long-term stability of passive margin escarpment constrained by 40Ar/39Ar dating of K-Mn oxides. Geology 44:299–302. https://doi.org/10.1130/G37303.1
Beauvais A, Ruffet G, Hénocque O, Colin F (2008) Chemical and physical erosion rhythms of the West African Cenozoic morphogenesis: the 39Ar-40Ar dating of supergene K-Mn oxides. J Geophys Res 113. https://doi.org/10.1029/2008JF000996
Bell BA, Hughes PD, Fletcher WJ et al (2022) Climate of the Marrakech High Atlas, Morocco: temperature lapse rates and precipitation gradient from piedmont to summits. Arct Antarct Alp Res 54:78–95. https://doi.org/10.1080/15230430.2022.2046897
Bonnet NJ, Beauvais A, Arnaud N et al (2016) Cenozoic lateritic weathering and erosion history of Peninsular India from 40 Ar/ 39 Ar dating of supergene K-Mn oxides. Chem Geol 446:33–53. https://doi.org/10.1016/j.chemgeo.2016.04.018
Bouabdellah M, Sangster DF, Leach DL et al (2012) Genesis of the Touissit-Bou Beker Mississippi Valley-Type District (Morocco-Algeria) and its relationship to the Africa-Europe collision. Econ Geol 107:117–146. https://doi.org/10.2113/econgeo.107.1.117
Bouabdellah M, Niedermann S, Velasco F (2015) The Touissit-Bou Beker Mississippi Valley-Type District of Northeastern Morocco: relationships to the Messinian Salinity Crisis, Late Neogene-Quaternary Alkaline Magmatism, and Buoyancy-Driven Fluid Convection. Econ Geol 110:1455–1484. https://doi.org/10.2113/econgeo.110.6.1455
Bouabdellah M, Maacha L, Jébrak M, Zouhair M (2016) Re/Os age determination, lead and sulphur isotope constraints on the origin of the Bouskour Cu–Pb–Zn vein-type deposit (Eastern Anti-Atlas, Morocco) and its relationship to neoproterozoic granitic magmatism. In: Bouabdellah M, Slack JF (eds) Mineral Deposits of North Africa. Springer International Publishing, Cham, pp 277–290
Bouabdellah M, Boukirou W, Potra A et al (2021) Origin of the Moroccan Touissit-Bou Beker and Jbel Bou Dahar supergene non-sulfide biomineralization and its relevance to microbiological activity, late Miocene uplift and climate changes. Minerals 11:401. https://doi.org/10.3390/min11040401
Bouladon J, Jouravsky G (1952) Géologie des gites minéraux marocains: Manganèse. Congrès géologique international, Alger, pp 44–80
Cavallina C, Papini M, Moratti G, Benvenuti M (2018) The late Mesozoic evolution of the Central High Atlas domain (Morocco): evidence from the paleo-drainage record of the Adrar Aglagal syncline. Sed Geol 376:1–17. https://doi.org/10.1016/j.sedgeo.2018.08.003
Choubert G, Faure-Muret A (1973) The Precambrian iron and manganese deposits of the Anti-Atlas. In: Genesis of Precambrian iron and manganese deposits, Unesco Earth Sciences Symposium, v. 9, Kiev, pp 115–124
Choulet F, Charles N, Barbanson L et al (2014) Non-sulfide zinc deposits of the Moroccan High Atlas: multi-scale characterization and origin. Ore Geol Rev 56:115–140. https://doi.org/10.1016/j.oregeorev.2013.08.015
Colin F, Beauvais A, Ruffet G, Henocque O (2005) First 40Ar/39Ar geochronology of lateritic manganiferous pisolites: implications for the Palaeogene history of a West African landscape. Earth Planet Sci Lett 238:172–188. https://doi.org/10.1016/j.epsl.2005.06.052
Cornée J-J, Destombes J (1991) L’ordovicien de la partie W du massif ancien du Haut-Atlas occidental (Maroc hercynien). Geobios 24:403–415. https://doi.org/10.1016/S0016-6995(06)80238-X
De Putter T, Ruffet G (2020) Supergene manganese ore records 75 Myr-long Campanian to Pleistocene geodynamic evolution and weathering history of the Central African Great Lakes Region – Tectonics drives, climate assists. Gondwana Res 83:96–117. https://doi.org/10.1016/j.gr.2020.01.021
De Putter T, Ruffet G, Yans J, Mees F (2015) The age of supergene manganese deposits in Katanga and its implications for the Neogene evolution of the African Great Lakes Region. Ore Geol Rev 71:350–362. https://doi.org/10.1016/j.oregeorev.2015.06.015
Deckart K, Féraud G, Bertrand H (1997) Age of Jurassic continental tholeiites of French Guyana, Surinam and Guinea: implications for the initial opening of the Central Atlantic Ocean. Earth Planet Sci Lett 150:205–220. https://doi.org/10.1016/S0012-821X(97)00102-7
Decrée S, Deloule É, Ruffet G et al (2010) Geodynamic and climate controls in the formation of Mio-Pliocene world-class oxidized cobalt and manganese ores in the Katanga province, DR Congo. Miner Deposita 45:621–629. https://doi.org/10.1007/s00126-010-0305-8
Dekoninck A, Bernard A, Barbarand J et al (2016a) Detailed mineralogy and petrology of manganese oxyhydroxide deposits of the Imini district (Morocco). Miner Deposita 51:13–23. https://doi.org/10.1007/s00126-015-0590-3
Dekoninck A, Leprêtre R, Saddiqi O et al (2016b) The high-grade Imini manganese district—karst-hosted deposits of mn oxides and oxyhydroxides. In: Bouabdellah M, Slack JF (eds) Mineral Deposits of North Africa. Springer International Publishing, Cham, pp 575–594
Dekoninck A, Monié P, Blockmans S et al (2019) Genesis and 40Ar/39Ar dating of K-Mn oxides from the Stavelot Massif (Ardenne, Belgium): insights into Oligocene to Pliocene weathering periods in Western Europe. Ore Geol Rev 115:103–191. https://doi.org/10.1016/j.oregeorev.2019.103191
Dekoninck A, Ruffet G, Missenard Y et al (2021) Multistage genesis of the late Cretaceous manganese karst-hosted Tasdremt deposit (High Atlas, Morocco). Miner Deposita 59:935–956. https://doi.org/10.1007/s00126-020-01017-0
El Arabi EH, Diez JB, Broutin J, Essamoud R (2006) Première caractérisation palynologique du Trias moyen dans le Haut Atlas; implications pour l’initiation du rifting téthysien au Maroc. CR Geosci 338:641–649. https://doi.org/10.1016/j.crte.2006.04.001
El Harfi A, Lang J, Salomon J, Chellai E (2001) Cenozoic sedimentary dynamics of the Ouarzazate foreland basin (Central High Atlas Mountains, Morocco). Int J Earth Sci 90:393–411. https://doi.org/10.1007/s005310000115
Fekkak A, Ouanaimi H, Michard A et al (2018) Thick-skinned tectonics in a Late Cretaceous-Neogene intracontinental belt (High Atlas Mountains, Morocco): the flat-ramp fault control on basement shortening and cover folding. J Afr Earth Sc 140:169–188. https://doi.org/10.1016/j.jafrearsci.2018.01.008
Frizon de Lamotte D, Saint Bezar B, Bracène R, Mercier E (2000) The two main steps of the Atlas building and geodynamics of the western Mediterranean. Tectonics 19:740–761. https://doi.org/10.1029/2000TC900003
Frizon de Lamotte D, Zizi M, Missenard Y et al (2008) The Atlas System. In: Michard A, Saddiqi O, Chalouan A, de Lamotte DF (eds) Continental Evolution: The Geology of Morocco. Springer, Berlin Heidelberg, Berlin, Heidelberg, pp 133–202
Frizon de Lamotte D, Leturmy P, Missenard Y et al (2009) Mesozoic and Cenozoic vertical movements in the Atlas system (Algeria, Morocco, Tunisia): an overview. Tectonophysics 475:9–28. https://doi.org/10.1016/j.tecto.2008.10.024
Froitzheim N, Stets J, Wurster P (1988) Aspects of Western High Atlas tectonics. In: Jacobshagen VH (ed) The Atlas System of Morocco. Springer-Verlag, Berlin/Heidelberg, pp 219–244
Froitzheim N (1984) Late Cretaceous vertical tectonics in the High Atlas SW of Marrakech/Morocco -Reconstruction of tectonic movements in an early stage of the High Atlas orogenesis. Neu Jb Paläont Mh 8:463–471
Fullea J, Fernàndez M, Afonso JC et al (2010) The structure and evolution of the lithosphere–asthenosphere boundary beneath the Atlantic-Mediterranean Transition Region. Lithos 120:74–95. https://doi.org/10.1016/j.lithos.2010.03.003
Garnit H, Kraemer D, Bouhlel S et al (2020) Manganese ores in Tunisia: genetic constraints from trace element geochemistry and mineralogy. Ore Geol Rev 120:103451. https://doi.org/10.1016/j.oregeorev.2020.103451
Gasquet D, Levresse G, Cheilletz A et al (2005) Contribution to a geodynamic reconstruction of the Anti-Atlas (Morocco) during Pan-African times with the emphasis on inversion tectonics and metallogenic activity at the Precambrian-Cambrian transition. Precambr Res 140:157–182. https://doi.org/10.1016/j.precamres.2005.06.009
Groves DI, Bierlein FP (2007) Geodynamic settings of mineral deposit systems. J Geol Soc 164:19–30. https://doi.org/10.1144/0016-76492006-065
Gutzmer J, Beukes NJ, Rhalmi M, Mukhopadhyay J (2006) Cretaceous karstic cave-fill manganese-lead-barium deposits of Imini, Morocco. Econ Geol 101:385–405. https://doi.org/10.2113/gsecongeo.101.2.385
Hanes JA, York D, Hall CM (1985) An 40Ar/39Ar geochronological and electron microprobe investigation of an Archaean pyroxenite and its bearing on ancient atmospheric compositions. Can J Earth Sci 22:947–958. https://doi.org/10.1139/e85-100
Hautmann S, Lippolt HJ (2000) 40Ar/39Ar dating of central European K-Mn oxides — a chronological framework of supergene alteration processes during the Neogene. Chem Geol 170:37–80. https://doi.org/10.1016/S0009-2541(99)00241-7
Hénocque O, Ruffet G, Colin F, Féraud G (1998) 40Ar/39Ar dating of West African lateritic cryptomelanes. Geochim Cosmochim Acta 62:2739–2756. https://doi.org/10.1016/S0016-7037(98)00185-9
Herbig H-G (1988) Synsedimentary tectonics in the Northern Middle Atlas (Morocco) during the late Cretaceous and Tertiary. In: Jacobshagen VH (ed) The Atlas system of Morocco: studies on its geodynamic evolution. Springer, Berlin Heidelberg, Berlin, Heidelberg, pp 321–337
Jean A, Beauvais A, Chardon D et al (2019) Weathering history and landscape evolution of Western Ghats (India) from 40Ar/39Ar dating of supergene K-Mn oxides. J Geol Soc. https://doi.org/10.1144/jgs2019-048
Lanari R, Fellin MG, Faccenna C et al (2020) Exhumation and surface evolution of the Western High Atlas and surrounding regions as constrained by low-temperature thermochronology. Tectonics 39:e2019TC005562. https://doi.org/10.1029/2019TC005562
Lanari R, Reitano R, Giachetta E et al (2022) Is the Anti-Atlas of Morocco still uplifting? J Afr Earth Sci 188:104481. https://doi.org/10.1016/j.jafrearsci.2022.104481
Landing E, Bowring SA, Davidek KL et al (1998) Duration of the Early Cambrian: U-Pb ages of volcanic ashes from Avalon and Gondwana. Can J Earth Sci 35:329–338. https://doi.org/10.1139/e97-107
Laznicka P (2014) Giant metallic deposits—a century of progress. Ore Geol Rev 62:259–314. https://doi.org/10.1016/j.oregeorev.2014.03.002
Lee J-Y, Marti K, Severinghaus JP et al (2006) A redetermination of the isotopic abundances of atmospheric Ar. Geochim Cosmochim Acta 70:4507–4512. https://doi.org/10.1016/j.gca.2006.06.1563
Leprêtre R, Missenard Y, Saint-Bezar B et al (2015) The three main steps of the Marrakech High Atlas building in Morocco: structural evidences from the southern foreland, Imini area. J Afr Earth Sc 109:177–194. https://doi.org/10.1016/j.jafrearsci.2015.05.013
Leprêtre R, Missenard Y, Barbarand J et al (2018) Polyphased inversions of an intracontinental rift: case study of the Marrakech High Atlas, Morocco. Tectonics 37:818–841. https://doi.org/10.1002/2017TC004693
Lippolt HJ, Hautmann S (1995) 40Ar/39Ar ages of Precambrian manganese ore minerals from Sweden, India and Morocco. Miner Deposita 30:246–256. https://doi.org/10.1007/BF00196360
Mansour A, Wagreich M, Gier S et al (2021) Climate variability and paleoceanography during the Late Cretaceous: evidence from palynology, geochemistry and stable isotopes analyses from the southern Tethys. Cretaceous Res 126:104831. https://doi.org/10.1016/j.cretres.2021.104831
Martin J (1982) Le Moyen Atlas Central, étude géomorphologique. Notes Et Mémoires Du Service Géologique Du Maroc 258:445
Marzoli A, Bertrand H, Youbi N et al (2019) The Central Atlantic magmatic province (CAMP) in Morocco. J Petrol. https://doi.org/10.1093/petrology/egz021
McCuaig TC, Scarselli S, O’Connor T et al (2018) The Power of a Systems Approach to Mineral and Petroleum Exploration in Sedimentary Basins. In: Arribas RAM, Mauk JL (eds) Metals, Minerals, and Society. Society of Economic Geologists (SEG), v.21, pp 39–62
Missenard Y, Taki Z, Frizon de Lamotte D et al (2007) Tectonic styles in the Marrakesh High Atlas (Morocco): the role of heritage and mechanical stratigraphy. J Afr Earth Sc 48:247–266. https://doi.org/10.1016/j.jafrearsci.2007.03.007
Missenard Y, Zeyen H, Frizon de Lamotte D et al (2006) Crustal versus asthenospheric origin of relief of the Atlas Mountains of Morocco. J Geophys Res Solid Earth 111:B03401. https://doi.org/10.1029/2005JB003708
Pouit G (1964) Les gîtes de manganèse marocains encaissés dans les Formations carbonatées : éléments pour une synthèse. Chronique des Mines et de la Recherche Minière 3397:371–380
Rhalmi M (1992) Les systèmes sédimentaires cénomano-turoniens et sénoniens de la région manganésifère d’Imini (Haut-Atlas Central, Maroc) et leur évolution diagénétique. PhD, Bourgogne
Rhalmi M, Pascal A, Lang J (1997) Contrôle sédimentaire et diagénétique de la minéralisation manganésifère au cours du Crétacé Supérieur dans la région d’Imini (Haut-Atlas central, Maroc). Comptes rendus de l’Académie des sciences Série 2 Sciences de la terre et des planètes 323:213–220
Rhalmi M, Pascal A, Chellai E (2000) Lithobiostratigraphie, diagenèse et paléogéographie au Cénomanien supérieur-Turonien inférieur des bassins sud-atlasiques marocains. Géologie Alpine 76:135–149
Rhalmi M, Chellai EH, Michard A (2011) Mine d’Imini : manganèse stratiforme dans les couches du Crétacé. In: Mouttaqi A, Rjimati EC, Maacha L, et al. (eds) Les principales mines du Maroc, Service géologique du Maroc. Notes et mémoires du service géologique, Rabat, v.9, pp 75–79
Roddick JC, Cliff RA, Rex DC (1980) The evolution of excess argon in alpine biotites - a 40Ar-39Ar analysis. Earth Planet Sci Lett 48:185–208. https://doi.org/10.1016/0012-821X(80)90181-8
Ruddiman WF, Raymo ME, Prell WL, Kutzbach JE (1997) The uplift-climate connection: a synthesis. In: Ruddiman WF (ed) Tectonic Uplift and Climate Change. Springer, US, Boston, MA, pp 471–515
Ruffet G, Innocent C, Michard A et al (1996) A geochronological and study of K-Mn oxides from the weathering sequence of Azul, Brazil. Geochim Cosmochim Acta 60:2219–2232. https://doi.org/10.1016/0016-7037(96)00080-4
Thein J (1990) Paleogeography and geochemistry of the “Cenomano-Turonian” formations in the manganese district of Imini (Morocco) and their relation to ore deposition. Ore Geol Rev 5:257–291. https://doi.org/10.1016/0169-1368(90)90034-K
Thomas RJ, Fekkak A, Ennih N et al (2004) A new lithostratigraphic framework for the Anti-Atlas Orogen, Morocco. J Afr Earth Sc 39:217–226. https://doi.org/10.1016/j.jafrearsci.2004.07.046
Turner G (1971) Argon 40-argon 39 dating: the optimization of irradiation parameters. Earth Planet Sci Lett 10:227–234. https://doi.org/10.1016/0012-821X(71)90010-0
Vasconcelos PM (1999) K-Ar and 40Ar/39Ar geochronology of weathering processes. Annu Rev Earth Planet Sci 27:183–229. https://doi.org/10.1146/annurev.earth.27.1.183
Vasconcelos PM, Renne PR, Becker TA, Wenk H-R (1995) Mechanisms and kinetics of atmospheric, radiogenic, and nucleogenic argon release from cryptomelane during analysis. Geochim Cosmochim Acta 59:2057–2070. https://doi.org/10.1016/0016-7037(95)00126-3
Vasconcelos PM, de Carmo I, O (2018) Calibrating denudation chronology through 40Ar/39Ar weathering geochronology. Earth Sci Rev 179:411–435. https://doi.org/10.1016/j.earscirev.2018.01.003
Verhaert M, Madi A, Basbas AE et al (2020) Genesis of As-Pb-rich supergene mineralization: the Tazalaght and Agoujgal Cu Deposits (Moroccan Anti-Atlas Copperbelt). Econ Geol 115:1725–1748. https://doi.org/10.5382/econgeo.4779
Verhaert M, Gautheron C, Dekoninck A et al (2022) Unravelling the temporal and chemical evolution of a mineralizing fluid in karst-hosted deposits: a record from goethite in the high atlas foreland (morocco). Minerals 12:1151. https://doi.org/10.3390/min12091151
Verhaert M, Bernard A, Dekoninck A et al (2017) Mineralogical and geochemical characterization of supergene Cu–Pb–Zn–V ores in the Oriental High Atlas, Morocco. Miner Deposita 52:1049–1068. https://doi.org/10.1007/s00126-017-0753-5
Wijbrans JR, McDougall I (1986) 40Ar/39Ar dating of white micas from an Alpine high-pressure metamorphic belt on Naxos (Greece): the resetting of the argon isotopic system. Contr Mineral Petrol 93:187–194. https://doi.org/10.1007/BF00371320
York D (1968) Least squares fitting of a straight line with correlated errors. Earth Planet Sci Lett 5:320–324. https://doi.org/10.1016/S0012-821X(68)80059-7
York D, Evensen NM, Martı́nez ML, De Basabe Delgado J (2004) Unified equations for the slope, intercept, and standard errors of the best straight line. Am J Physics 72:367–375. https://doi.org/10.1119/1.1632486
Zammit R, Lear CH, Samankassou E et al (2022) Early Miocene intensification of the North African hydrological cycle: multi-proxy evidence from the shelf carbonates of Malta. Paleoceanography Paleoclimatol 37:e2022PA004414. https://doi.org/10.1029/2022PA004414
Zouhri S, Kchikach A, Saddiqi O et al (2008) The Cretaceous-tertiary Plateaus. In: Michard A, Saddiqi O, Chalouan A, de Lamotte DF (eds) Continental Evolution: The Geology of Morocco. Springer, Berlin Heidelberg, Berlin, Heidelberg, pp 331–358
Acknowledgements
We are grateful to all those involved in the field missions carried out between 2012 and 2018. We acknowledge the “Office National des Mines et des Hydrocarbures” (ONHYM) for having shared their logistical and scientific support. We are very grateful to the Imini mine (SACEM) for providing field access and assistance in the field. We are thankful to Prof. M. Essalhi (University Moulay Ismail Errachidia), Th. Mortier (UMons), Z. Pirotte (ULB), B. Saint-Bézar (PSUD), and G. Delpech (PSUD) for field assistance. We appreciate the help of Prof. J. Wouters and Dr. N. Tumanov of the PC2 platform (UNamur) for collecting XRD patterns. We also thank G. Rochez for gathering field pictures and the preparation of sections and sample powders. Co-authors would like to warmly thank Jeroen De Jong for his assistance during the isotopic analyses and the “Fonds National de la Recherche Scientifique” (FNRS) for funding support in lab instruments. This research used the resources of the Electron Microscopy Service located at the University of Namur (“Plateforme Technologique Morphologie — Imagerie”). This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. We are very grateful to Prof. M. Bouabdellah and Prof. J. Gutzmer for their careful review of the paper, as well as Prof. G. Beaudoin for editing the final version.
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Supplementary file1 Additional file 1: Details of the 40Ar/39Ar and Pb isotope analytical procedures. Additional file 2: Lead, uranium, and thorium abundances and lead isotope compositions of the Tasdremt-Imini Mn ores and rocks from Neoproterozoic to late Cretaceous. AA=Anti-Atlas; S=Siroua; S-MHA= Southern Marrakech High Atlas; M-MHA= Middle Marrakech High Atlas; MA= Middle Atlas. Initial ages of Neoproterozoic volcanic rocks are from Gasquet et al. (2005), Neoproterozoic Mn ores are from Lippolt and Hautmann (1995), Cambrian basalts are from Landing et al. (1998), Ordovician shales are from Cornée and Destombes (1991), Triassic basalts are from Marzoli et al. (2019), Triassic red sandstones are from El Arabi et al. (2006), CT dolostones are from Rhalmi et al. (2000, 1997), Senonian sediments are from Algouti et al. (1999), Tasdremt Mn ores are from Dekoninck et al. (2021). Additional file 3: Analytical data and parameters used for calculations of 40Ar/39Ar results. Pure K, Ca, and Cl salts; mass discrimination; atmospheric argon ratios; J-parameter; and decay constants. Additional file 4: Major and trace element geochemistry. Additional file 5: K-Ar ages of coronadite group minerals in the Imini deposits. No ages are relevant for this study given the complexity of the Ar/Ar spectra. Additional file 6: 208Pb/204Pb vs 207Pb/204Pb and 208Pb/204Pb vs 206Pb/204Pb plots of the Imini and Tasdremt Mn ores and potential source rocks. Additional file 7: Altered basalts in the Atlas range. a Microscopic view of blue chayesite [K(Mg,Fe2+)4Fe3+Si12O30] under polarized light in Triassic basalt at Telouet (Figs. 1b and 2a). b Microscopic view of silicified Triassic basalt with chlorite-quartz druses under polarized light at Toufliht (Fig. 1b) (PDF 3238 KB)
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Dekoninck, A., Barbarand, J., Ruffet, G. et al. Intraplate orogenesis as a driver of multistage karst-hosted mineralization: the Imini manganese case (Atlas, Morocco). Miner Deposita 59, 453–472 (2024). https://doi.org/10.1007/s00126-023-01212-9
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DOI: https://doi.org/10.1007/s00126-023-01212-9