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Eruption of kimberlite magmas: physical volcanology, geomorphology and age of the youngest kimberlitic volcanoes known on earth (the Upper Pleistocene/Holocene Igwisi Hills volcanoes, Tanzania)

Abstract

The Igwisi Hills volcanoes (IHV), Tanzania, are unique and important in preserving extra-crater lavas and pyroclastic edifices. They provide critical insights into the eruptive behaviour of kimberlite magmas that are not available at other known kimberlite volcanoes. Cosmogenic 3He dating of olivine crystals from IHV lavas and palaeomagnetic analyses indicates that they are Upper Pleistocene to Holocene in age. This makes them the youngest known kimberlite bodies on Earth by >30 Ma and may indicate a new phase of kimberlite volcanism on the Tanzania craton. Geological mapping, Global Positioning System surveying and field investigations reveal that each volcano comprises partially eroded pyroclastic edifices, craters and lavas. The volcanoes stand <40 m above the surrounding ground and are comparable in size to small monogenetic basaltic volcanoes. Pyroclastic cones consist of diffusely layered pyroclastic fall deposits comprising scoriaceous, pelletal and dense juvenile pyroclasts. Pyroclasts are similar to those documented in many ancient kimberlite pipes, indicating overlap in magma fragmentation dynamics between the Igwisi eruptions and other kimberlite eruptions. Characteristics of the pyroclastic cone deposits, including an absence of ballistic clasts and dominantly poorly vesicular scoria lapillistones and lapilli tuffs, indicate relatively weak explosive activity. Lava flow features indicate unexpectedly high viscosities (estimated at >102 to 106 Pa s) for kimberlite, attributed to degassing and in-vent cooling. Each volcano is inferred to be the result of a small-volume, short-lived (days to weeks) monogenetic eruption. The eruptive processes of each Igwisi volcano were broadly similar and developed through three phases: (1) fallout of lithic-bearing pyroclastic rocks during explosive excavation of craters and conduits; (2) fallout of juvenile lapilli from unsteady eruption columns and the construction of pyroclastic edifices around the vent; and (3) effusion of degassed viscous magma as lava flows. These processes are similar to those observed for other small-volume monogenetic eruptions (e.g. of basaltic magma).

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References

  1. Bassett H (1954) The Igwisi craters and lavas. Rec Geol Surv Tanganyika 4:81–92

  2. Batumike JM, Griffin WL, Belousova NJ, Pearson NJ, O’Reilly SY, Shee SR (2008) LAM-ICPMS U-Pb dating of kimberlitic perovskite: Eocene–Oligocene kimberlites from the Kundelungu Plateau, D.R. Congo. Earth Planet Sci Lett 267:609–619

  3. Bell K, Dodson MH (1981) The geochronology of the Tanzanian shield. J Geol 89:109–128

  4. Berryman A, Scott Smith BH, Jellicoe B (2004) Geology and diamond distribution of the 140/141 kimberlite, Fort à la Corne, central Saskatchewan, Canada. Lithos 76:99–114

  5. Brown RJ, Buse B, Sparks RSJ, Field M (2008a) On the welding of pyroclasts from very low–viscosity magmas: examples from kimberlite volcanoes. J Geol 116:354–374

  6. Brown RJ, Gernon T, Steifenhofer FM (2008b) Geological constraints on the eruption of the Jwaneng central kimberlite pipe, Botswana. J Volcanol Geotherm Res 174:195–208

  7. Brown RJ, Tait M, Field M, Sparks RSJ (2009) Geology of a complex kimberlite pipe (K2 pipe, Venetia mine, South Africa): insights into conduit processes during explosive ultrabasic eruptions. Bull Volcanol 71:95–112

  8. Buisman I, Sparks RSJ, Manya S, Brown RJ, Kavanagh J, Walter MJ (2012) Olivine chemistry of exceptionally young (Holocene) kimberlite of the IHV, Tanzania. Contrib Min Pet (in press)

  9. Buse B, Schumacher JC, Sparks RSJ, Field M (2010) Growth of bultfonteinite and hydrogarnet in metasomatized basalt xenoliths in the B/K9 kimberlite, Damtshaa, Botswana: insights into hydrothermal metamorphism in kimberlite pipes. Contrib Min Pet 160:533–550

  10. Cas RAF, Wright JV (1987) Volcanic successions. Chapman and Hall, London, p 528

  11. Cas RAF, Hayman P, Pittari A, Porritt L (2008) Some major problems with existing models and terminology associated with kimberlite pipes from a volcanological perspective, and some suggestions. J Volcanol Geotherm Res 174:209–225

  12. Castrucchio A, Rust A, Sparks RSJ (2010) Rheology and flow of crystal-rich bearing lavas: insights from analogue gravity currents. Earth Planet Sci Lett 297:471–480

  13. Davis GL (1977) The ages and uranium contents of zircons from kimberlites and associated rocks. Carnegie Institute Washington 76:631–635

  14. Dawson JB (1964) Carbonate tuff cones in northern Tanganyika. Geol Mag 101:129–137

  15. Dawson JB (1971) Advances in kimberlite geology. Earth Sci Rev 7:187–214

  16. Dawson JB (1994) Quaternary kimberlitic volcanism on the Tanzania craton. Contrib Min Pet 116:473–485

  17. Dawson JB, Hawthorne JB (1973) Magmatic sedimentation and carbonatitic differentiation in kimberlite sills at Benfontein, South Africa. J Geol Soc London 129:61–85

  18. Dawson JB, Powell DG (1969) The Natron-Engaruka explosion crater area, Northern Tanzania. Bull Volcanol 33:761–817

  19. Doubik P, Hill BE (1999) Magmatic and hydromagmatic conduit development during the 1975 Tolbachik Eruption, Kamchatka, with implications for hazards assessment at Yucca Mountain, NV. J Volcanol Geotherm Res 91:43–64

  20. Douce AEP, Beard JS (1994) Dehydration melting of biotite gneiss and quartz amphibolite from 3 to 15 kbar. J Pet 36:707–738

  21. Dunai TJ (2000) Scaling factors for production rates of in situ produced cosmogenic nuclides: a critical reevaluation. Earth Planet Sci Lett 176:157–169

  22. Eley R, Grütter H, Louw A, Tunguno C, Twidale J (2008) Exploration geology of the Luxinga kimberlite cluster (Angola) with evidence supporting the presence of kimberlite lava. Extended Abstract 9th Int. Kimberlite Conf

  23. Field M, Scott Smith BH (1999) Contrasting geology and near-surface emplacement of kimberlite pipes in southern Africa and Canada. In: Gurney J, Gurney J, Pascoe M, Richardson S (eds) J.B. Dawson Volume. Proceedings of the VIIth International Kimberlite Conference, vol 1. Red Roof design cc, Cape Town, 214–237

  24. Field M, Gibson JG, Wilkes TA, Gababotse J, Khutjwe P (1997). The geology of the Orapa A/K1 Kimberlite, Botswana: further insight into the emplacement of kimberlite pipes. In: Dobretsov NL, Goldin SV, Kontorovich AE, Polyakov GV, Sobolev NV (eds) Proceedings of the Sixth International Kimberlite Conference 1: kimberlites, related rocks and mantle xenoliths. Russian Geology and Geophysics, Novosibirsk, Russia, 24–39

  25. Field M, Stiefenhofer J, Robey J, Kurszlaukis S (2008) The kimberlite-hosted diamond deposits of southern Africa: a review. Ore Geology Reviews 34:33–75

  26. Fisher RV, Schmincke H-U (1984) Pyroclastic rocks. Springer, Berlin

  27. Foeken JPT, Persano C, Stuart FM, ter Voorde M (2007) Role of topography in isotherm perturbation: apatite (U-Th)/He and fission track results from the Malta tunnel, Tauern Window, Austria. Tectonics 26:1–15

  28. Fontana GPG, Mac Niocaill C, Brown RJ, Sparks RSJ, Field M (2011) Emplacement temperatures of pyroclastic and volcaniclastic deposits in kimberlite pipes in southern Africa. Bull Volcanol 73:1063–1083

  29. Fozzard PMH (1956) Further notes on the volcanic rocks from Igwisi, Tanganyika. Rec Geol Surv Tanganyika 6:69–75

  30. Gernon T, Gilbertson M, Sparks RSJ, Field M (2008a) Gas-fluidisation in an experimental tapered bed: Insights into processes in diverging volcanic conduits. J Volcanol Geotherm Res 174:49–56

  31. Gernon T, Sparks RSJ, Field M (2008b) Degassing structures in volcaniclastic kimberlite: examples from southern African pipes. J Volcanol Geotherm Res 174:186–194

  32. Gernon TM, Fontana G, Field M, Sparks RSJ, Brown RJ, Mac Niocaill C (2009a) Pyroclastic flow deposits from a kimberlite eruption: the Orapa south crater, Botswana. Lithos 112:566–578

  33. Gernon TM, Fontana G, Field M, Sparks RSJ (2009b) Depositional processes in a kimberlite crater: the Upper Cretaceous Orapa South Pipe (Botswana). Sedimentology 56:623–643

  34. Gobba JM (1989) Kimberlite exploration in Tanzania. J African Earth Sci 9(314):565–578

  35. Goehring BM, Kurz MD, Balco G, Schaefer JM, Licciardi J, Lifton NA (2010) Reevaluation of in situ cosmogenic (3)He production rates. Quat Geochron 5:410–418

  36. Haggerty SE, Raber E, Naeser CW (1983) Fission track dating of kimberlite zircons. Earth Planet Sci Lett 63:41–50

  37. Hawthorne JB (1975) Model of a kimberlite pipe. Phys Chem Earth 9:1–15

  38. Junqueira-Brod TC, Brod JA, Gaspar JC, Jost H (2004) Kamafugitic diatremes: facies characterisation and genesis—examples from the Goiás alkaline province, Brazil. Lithos 76:261–282

  39. Keating GN, Valentine GA, Krier DJ, Perry FV (2008) Shallow plumbing systems for small-volume basaltic volcanoes. Bull Volcanol 70:563–582

  40. Kjarsgaard BA (2007). Kimberlite diamond deposits. In: Goodfellow WD (ed) Mineral deposits of Canada: a synthesis of major deposit types, district metallogeny, the evolution of geological provinces, and exploration methods. Geological Association of Canada, Mineral Deposits Division, Special Publication 5:245–272

  41. Kjarsgaard BA, Leckie DA, Zonneveld J–P (2007). Discussion of “Geology and diamond distribution of the 140/141 kimberlite, Fort à la Corne, central Saskatchewan, Canada” by Berryman AK, Scott Smith BH, Jellicoe BC (Lithos 76:99–114). Lithos 97:422–428

  42. Kjarsgaard BA, Harvey S, McClintock M, Zonneveld JP, Du Plessis P, McNeil D, Heaman L (2009) Geology of the Orion South kimberlite, Fort à la Corne, Canada. Lithos 1125:600–617

  43. Kurszlaukis S, Barnett WP (2003) Volcanological and structural aspects of the Venetia Kimberlite cluster—a case study of South African kimberlite maar-diatreme volcanoes. South African J Earth Sci 106:165–192

  44. Kurszlaukis S, Lorenz V (2008) Formation of “Tuffisitic Kimberlite” by phreatomagmatic processes. J Volcanol Geotherm Res 174:68–80

  45. Kurz MD, Colodner D, Trull TW, Sampson DE (1987) Exposure age dating with cosmogenic3He: influence of the Earth's magnetic field. Eos 68:1286

  46. Leckie DA, Kjarsgaard BA, Bloch J, McIntyre D, McNeil D, Stasiuk L, Heaman L (1997) Emplacement and reworking of Cretaceous, diamond-bearing, crater facies kimberlite of central Saskatchewan, Canada. Geol Soc Am Bull 109:1000–1020

  47. Lefebvre N, Kurszlaukis S (2008) Contrasting eruption styles of the 147 kimberlite, Fort à la Corne, Saskatchewan, Canada. J Volcanol Geotherm Res 174:171–185

  48. Lorenz V (1975) Formation of phreatomagmatic maar-diatreme volcanoes and its relevance to kimberlite diatremes. Phys Chem Earth 9:17–27

  49. Lorenz V (2007) Syn- and post-eruptive hazards of maar-diatreme volcanoes. J Volcanol Geotherm Res 159:285–312

  50. Lorenz V, Kurszlaukis S (2007) Root zone processes in the phreatomagmatic pipe emplacement model and consequences for the evolution of maar-diatreme volcanoes. J Volcanol Geotherm Res 159:4–32

  51. Mainkar D, Lehmann B, Haggerty SE (2004) The crater–facies kimberlite system of Tokapal, Bastar district, Chhattisgarh, India. Lithos 76:201–217

  52. Mattsson HB, Tripoli BA (2011) Depositional characteristics and volcanic landforms in the lake Natron-Engaruka monogenetic field, northern Tanzania. J Volcanol Geotherm Res 203:23–34

  53. McClintock M, White JDL, Houghton BF, Skilling IP (2008) Physical volcanology of a large crater-complex formed during the initial stages of Karoo flood basalt volcanism, Sterkspruit, Eastern Cape, South Africa. J Volcanol Geotherm Res 172:93–111

  54. McGetchin TR, Settle M, Chouet BA (1974) Cinder cone growth modeled after northeast crater, Mount Etna, Sicily. J Geophys Res 79:3257–3272

  55. Mitchell RH (1970) Kimberlite and related rocks—a critical reappraisal. J Geol 78:686–704

  56. Mitchell RH (1986). Kimberlites. Mineralogy, geochemistry and petrology. Plenum, New York

  57. Mitchell RH (2008) Petrology of hypabyssal kimberlites: relevance to primary magma compositions. J Volcanol Geotherm Res 174:1–8

  58. Moss S, Russell JK (2011) Fragmentation in kimberlite: products and intensity of explosive eruptions. Bull Volcanol 72:983–1003

  59. Moss S, Russell JK, Andrews GDM (2008) Progressive infilling of a kimberlite pipe at Diavik, Northwest Territories, Canada: insights from volcanic facies architecture, textures, and granulometry. J Volcanol Geotherm Res 174:103–116

  60. Newhall CG, Self S (1982) The volcanic explosivity index (VEI): an estimate of explosive magnitude for historical volcanism. J Geophys Res 87:123–1238

  61. Pirrung M, Büchel G, Lorenz V, Treutler H (2008) Post-eruptive development of the Ukinrek east maar since its eruption in 1977 A.D. in the periglacial area of south–west Alaska. Sedimentology 55:305–334

  62. Pittari A, Cas RAF, Lefebvre N, Robey J, Kurszlaukis S, Webb K (2006) Eruption processes and facies architecture of the Orion central kimberlite volcanic complex, Fort a la Corne, Saskatchewan; kimberlite mass flow deposits in a sedimentary basin. J Volcanol Geotherm Res 174:152–170

  63. Porritt LA, Russell JK (2012) Kimberlite ash: fact or fiction? Phys Chem Earth (in press)

  64. Porritt LA, Cas R, Crawford BB (2008) In-vent column collapse as an alternative model for massive volcaniclastic kimberlite emplacement: an example from the Fox kimberlite, Ekati Diamond Mine, NWT, Canada. J Volcanol Geotherm Res 174:90–102

  65. Porter SC (1972) Distribution, morphology, and size frequency of cinder cones on Mauna Kea Volcano, Hawaii. Geol Soc Am Bull 83:3607–3612

  66. Reid AM, Donaldson CH, Dawson JB, Brown RW, Ridley WI (1975) The Igwisi Hills extrusive “kimberlites”. Phys Chem Earth 9:199–218

  67. Ross P-S, White JD (2006) Debris jets in continental phreatomagmatic volcano: a field study of their subterranean rocks in the Coombs Hills vent complex, Antarctica. J Volcanol Geotherm Res 149:62–84

  68. Ross P-S, Delpit S, Haller MJ, Németh K, Corbella H (2011) Influence of the substrate on maar-diatreme volcanoes—an example of a mixed setting from the Pali Aike volcanic field, Argentina. J Volcanol Geotherm Res 201:253–271

  69. Rowland SK, Walker GPL (1988) Mafic-crystal distributions, viscosities, and lava structures of some Hawaiian lava flows. J Volcanol Geotherm Res 35:55–66

  70. Sampson DN (1953) The volcanic hills at Igwisi. Rec Geol Surv Tanganyika 3:48–53

  71. Skinner EMW, Marsh JS (2004) Distinct kimberlite pipe classes with contrasting eruption processes. Lithos 76:183–200

  72. Sparks RSJ, Baker L, Brown RJ, Field M, Schumacher J, Stripp G (2006) Dynamical constraints on kimberlite volcanism. J Volcanol Geotherm Res 155:18–48

  73. Stiefenhofer J, Farrow DJ (2004) Geology of the Mwadui kimberlite, Shinyanga district, Tanzania. Lithos 76:139–160

  74. Stripp GR, Field M, Schumacher JC, Sparks RSJ (2006) Post-emplacement serpentinization and related hydrothermal metamorphism in a kimberlite from Venetia, South Africa. J Met Geology 24:515–534

  75. Valentine GA (2012) Shallow plumbing systems for small-volume basaltic volcanoes, 2: evidence from crustal xenoliths at scoria cones and maars. J Volcanol Geotherm Res 223–224:47–63

  76. Valentine GA, Groves KR (2008) Entrainment of country rock during basaltic eruptions of the Lucero volcanic field, New Mexico. J Geol 104:71–90

  77. Van Straaten BI, Kopylova MG, Russell JK, Scott Smith BH (2011) A rare occurrence of a crater-filling clastogenic extrusive coherent kimberlite, Victor Northwest (Ontario, Canada). Bull Volcanol 73:1047–1062

  78. Walker GPL (1973) Lengths of lava flows. Phil Trans Roy Soc London 274:107–118

  79. Walters AL, Phillips JC, Brown RJ, Field M, Gernon T, Stripp G (2006) The role of fluidisation in the formation of volcaniclastic kimberlite: grain size observations and experimental investigation. J Volcanol Geotherm Res 155:119–137

  80. White JDL, Houghton BF (2006) Primary volcaniclastic rocks. Geology 34:677–680

  81. White JDL, Ross P-S (2011) Maar-diatreme volcanoes: a review. J Volcanol Geotherm Res 201:1–29

  82. Willcox A, Buisman I, Sparks RSJ, Brown RJ, Manya S, Schumacher JS, Tuffen H (2012) Petrology, geochemistry and low-temperature alteration of extrusive lavas and pyroclastic rocks of the Igwisi Hills kimberlites, Tanzania. Chem Geol. doi:10.1016/j.pce.2011.03.002

  83. Williams AJ, Stuart FM, Day SJ, Phillips WM (2005) Using pyroxene microphenocrysts to determine cosmogenic 3He concentrations in old volcanic rocks: an example of landscape development in central Gran Canaria. Quat Sci Rev 24:211–222

  84. Wohletz KH, Sheridan MF (1983) Hydrovolcanic explosions II. Evolution of basaltic tuff rings and tuff cones. Am J Sci 283:385–413

  85. Wood CA (1980) Morphometric evolution of cinder cones. J Volcanol Geotherm Res 7:387–413

  86. Zonneveld J-P, Kjarsgaard BA, Harvey SE, Heaman LM, McNeil DH, Marcia KY (2004) Sedimentologic and stratigraphic constraints on the emplacement of the Star kimberlite east–central Saskatchewan. Lithos 76:115–138

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Acknowledgements

We dedicate this paper to Barry Dawson—the last geologist to visit the volcanoes in 1966—as thanks for his great encouragement, advice and help and for many fruitful discussions throughout this study. Field and laboratory studies were supported a National Geographic Committee on Research and Exploration grant (no. 8562_08) awarded to RJB, the Natural Environment Research Council Geophysical Equipment Facility (grant no. 894) and the Royal Society International Travel Grant scheme. RSJS acknowledges support from a European Research Council Advanced grant. Alan Hobbs and Colin Kay at GEF are thanked for training and support. We thank Craig Storey and Dan Condon for advice on radiometric dating. We are indebted to Rod Smith of Cranbrook School, Kent, Mama Kisinga and the Friends of Urambo and Mwanhala charity for logistical support, lodgings, help and advice. We thank Urambo district council and the villagers at Igwisi for permission to work at the volcanoes. Bruce Kjarsgaard, Pierre-Simon Ross and Greg Valentine are thanked for expert reviews that greatly improved the manuscript. James White is thanked for editorial input and discussion.

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Correspondence to Richard J. Brown.

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Editorial responsibility: J.D.L. White

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Brown, R.J., Manya, S., Buisman, I. et al. Eruption of kimberlite magmas: physical volcanology, geomorphology and age of the youngest kimberlitic volcanoes known on earth (the Upper Pleistocene/Holocene Igwisi Hills volcanoes, Tanzania). Bull Volcanol 74, 1621–1643 (2012). https://doi.org/10.1007/s00445-012-0619-8

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Keywords

  • Kimberlite
  • Igwisi Hills
  • Explosive eruption
  • Lava
  • Monogenetic volcano