Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-23T21:51:19.439Z Has data issue: false hasContentIssue false

The agpaitic rocks - an overview*

Published online by Cambridge University Press:  05 July 2018

Henning Sørensen*
Affiliation:
Institute of Geology, The University of Copenhagen, Øster Voldgade 10, DK-1350 Copenhagen K

Abstract

It is now generally agreed that the term ‘agpaitic’ should be restricted to peralkaline nepheline syenites (and phonolites) containing minerals such as eudialyte and rinkite, that is complex silicates of Zr, Ti, the rare earth elements (REE), and F and other volatiles. There are, however, cases of transition into more common types of nepheline syenites containing zircon, titanite, ilmenite, etc.

The agpaitic rocks are characterized by extremely high contents of rare elements such as Li, Be, Nb, Ta, REE, Zr, Th, etc. and of volatiles, first of all F and Cl. This gives rise to a wealth of mineral species, more than 500 in the Lovozero and Khibina complexes of the Kola peninsula, about 250 in Mont Saint-Hilaire, Quebec, Canada, and about 200 in the type locality, the Ilímaussaq complex, South Greenland.

These rocks have very long melting intervals and solidus temperatures as low as 500 to 400°C. They are accompanied by a gas phase rich in methane and other hydrocarbons and most probably also by sodium-rich fluids as indicated by the presence of minerals such as ussingite (NaAlSi3O8·NaOH) and villiaumite (NaF) and of pegmatites and hydrothermal veins rich in sodium and rare and volatile elements.

Agpaitic nepheline syenites are considered to have been formed by consolidation of melts oversaturated in alkalis, especially sodium, under conditions preventing the volatiles from escaping. These melts have been derived by extreme fractionation processes in alkali basaltic or nephelinitic magmas. The main stage of crystallization of the melts is characterized by minerals such as nepheline (sometimes also sodalite), alkali feldspars, arfvedsonite, aegirine and eudialyte, but the most highly developed, hyperagpaitic lujavrites of the Ilímaussaq complex have been formed from melts with extreme concentrations of sodium and volatiles resulting in the formation of naujakasite instead of nepheline, ussingite instead of sodalite and alkali feldspars, and steenstrupine instead of eudialyte. During the late stages of crystallization, sodium-rich fluids are the cause of late- and postmagmatic alteration and of the formation of hydrothermal mineralizations. The late stages are characterized by water-soluble sodium-rich minerals of which more than 80 have been found in the Khibina and Lovozero complexes.

Type
Intraplate Alkaline Magmatism
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1997

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Andersen, S., Bailey, J.C. and Bohse, H. (1981) Zr-Y-U stratigraphy of the kakortokite-lujavrite sequence, southern Ilímaussaq intrusion. Rapp. Grølands geol. Unders., 103, 69-76.Google Scholar
Bailey, J. and Gwozdz, R. (1994) Li distribution in aegirine lujavrite, Ilímaussaq alkaline intrusion, South Greenland: role of cumulus and post-cumulus processes. Lithos, 31, 207-25.CrossRefGoogle Scholar
Bailey, J., Gwozdz, R., Rose-Hansen, J. and Sørensen, H. (1978) Preliminary geochemical work on the llímaussaq alkaline intrusion, South Greenland. Rapp. Grønlands geol. Unders., 90, 75-9.Google Scholar
Bailey, J., Rose-Hansen, J. and Sørensen, H. (1983) Leaching of uranium and thorium as a petrogenetic indicator in the agpaitic Ilímaussaq intrusion, South Greenland. In The Significance of Trace Elements in Solving Petrogenetic Problems and Controversies. Theophrastus Publ. Athens, 861-85.Google Scholar
Blaxland, A., van Breemen, O. and Steenfelt, A. (1976) Age and origin of agpaitic magmatism at Ilímaussaq, South Greenland: Rb-Sr study. Lithos, 9, 31-8.CrossRefGoogle Scholar
Blundell, D.J. (1978) A gravity survey across the Gardar igneous province, SW Greenland. J. Geol. Soc. London, 135, 545-54.CrossRefGoogle Scholar
Bøggild, O.B. (1903) On some minerals from the nephelite-syenite at Julianehaab, Greenland (erikite and schizolite). Meddel. Grønland, 26, 93-139.Google Scholar
Bouabdli, A., Dupuy, C. and Dostal, J. (1988) Geochemistry of Mesozoic alkaline lamprophyres and related rocks from the Tamazeght massif, High Atlas, Morocco. Lithos, 22, 43-58.CrossRefGoogle Scholar
Brøgger, W.V. (1890) Die Mineralien der Syenitpegmatitgäinge der Südnorwegischen Augit-und Nephelinsyenite. Zeits. Krist. - Mineral., 16, 1-235 and 1-663.Google Scholar
Brousse, R. and Rançon, J.Ph. (1984) Crystallization trends of pyroxenes from agpaitic phonolites (Cantal, France). Mineral. Mag., 48, 39—45.CrossRefGoogle Scholar
Buchwald, V.F. and Sørensen, H. (1961) An autoradio-graphic examination of rocks and minerals from the Ilímaussaq batholith, South West Greenland. Meddel. Gronland, 162, pt 11, 135.Google Scholar
Bussen, I.V. and Sakarov, A.S. (1972) Petrology of the Lovozero Alkaline Massif. Nauka, Moskva, 296 pp. (in Russian).Google Scholar
Chapman, N.A., McKinley, I.G., Shea, M.E. and Smellie, J.A.T. (eds.) (1992) The PoÇos de Caldas Project: Natural Analogues of Processes in a Radioactive Waste Repository. J. Geochem. Exploration, 45, 1—603.CrossRefGoogle Scholar
Currie, K.L. and van Breemen, O. (1996) The origin of rare minerals in the Kipawa syenite complex, western Quebec. Canad. Mineral., 34, 435—51.Google Scholar
Currie, K.L., Eby, G.N. and Gittins, J. (1986) The petrology of the Mont Saint Hilaire complex, southern Quebec: an alkaline gabbro-peralkaline syenite association. Lithos, 19, 65—81.CrossRefGoogle Scholar
Curtis, L.W. and Currie, K.L. (1981) Geology and petrology of the Red Wine Alkaline Complex, Central Labrador. Geol.Survey Canada Bull., 294, 1-61.Google Scholar
Danø, M. and Sørensen, H. (1959) An examination of some rare minerals from the nepheline syenites of South West Greenland. Meddel. Grønland, 162, pt 5, 139.Google Scholar
Dawson, J.B. and Frisch, T. (1971) Eucolite from Oldoinyo Lengai, Tanzania. Lithos, 4, 297—303.CrossRefGoogle Scholar
Edgar, A.D. and Parker, L.M. (1974) Comparison of melting relationships of some plutonic and volcanic peralkaline undersaturated rocks. Lithos 7, 263—73.CrossRefGoogle Scholar
Engell, J. (1973) A closed system crystal-fractionation model for the agpaitic Ilímaussaq intrusion, South Greenland, with special reference to the lujavrites. Bull. Geol. Soc. Denmark, 22, 334–62.Google Scholar
Engell, J., Hansen, J., Jensen, M., Kunzendorf, H. and Løvborg, L., (1971) Beryllium mineralization in the Ilímaussaq intrusion, South Greenland, with description of a field beryllometer and chemical methods. Bull. Grønlands geol. Unders., 33, 1-40.Google Scholar
Ferguson, J. (1973) The Pilanesberg alkaline province, Southern Africa. Trans. Geol. Soc. South Africa, 76, 249-70.Google Scholar
Forsberg, R. and Rasmussen, K.L. (1978) Gravity and rock densities in the llímaussaq area, South Greenland. Rapp. Grønlands geol. Unders., 90, 81-4.Google Scholar
Gerasimovsky, V.I. (1937) Erikite from the Lovozero tundra. Trans. Lomonosov Inst. USSR Academy of Sciences, 10, 29—36 (in Russian).Google Scholar
Gerasimovsky, V.I. (1969) Geochemistry of the Ilímaussaq alkaline massif. Nauka, Moskva, 174 pp, (in Russian, English summary).Google Scholar
Gerasimovsky, V.I., Volkov, V.P., Kogarko, L.N., Polyakov, A.I., Saprykina, T.V. and Balashov, Ju.A., (1966) Geochemistry of the Lovozero Alkaline Massif. Nauka, Moskva, 395 pp, (in Russian).Google Scholar
Girod, M. (1971) Le massif volcanique d L'Atakor (Hoggar, Sahara Algérien): Etude pétrographique, structurale et volcanologique. Centre National de la Recherche Scientifique, Paris, 158 pp.Google Scholar
Horvath, L. and Gault, R.A. (1990) The Mineralogy of Mont Saint-Hilaire, Quebec. Mineral. Record, 21, 284359.Google Scholar
Jones, A.P. and Larsen, L.M. (1985) Geochemistry and REE minerals of nepheline syenites from the Motzfeldt Centre, South Greenland. Amer. Mineral., 70, 1087-100.Google Scholar
Kadar, M. (1984) Minéralogie et implications pétrologiques des pegmatites des syénites néphéliniques du massif alcalin du Tamazeght (Haut Atlas de Midelt-Maroc). Thèse Laboratoire de Minéralogie et Cristallographie, Université Paul Sabatier, Toulouse, 146 pp.Google Scholar
Karup-Møller, S. (1983) Lomonosovite from the Ilímaussaq intrusion, South Greenland. Neues. Jahrb. Mineral. Abh., 148, 83-96.Google Scholar
Khadem Allah, B. (1993) Syènites et pegmatites néphéliniques du complex alcalin du Tamazeght (Haut Atlas de Midelt, Maroc). Thèse Laboratoire de Minéralogie. Université Paul Sabatier, Toulouse, 240 pp.Google Scholar
Khomyakov, A.P. (1990) Mineralogy of Hyperagpaitic Alkaline Rocks. Nauka, Moscow, 196 pp, (in Russian).Google Scholar
Khomyakov, A.P. (1995) Mineralogy of hyperagpaitic alkaline rocks. Oxford Scientific Publications. Clarendon Press, Oxford, 222 pp.Google Scholar
Kogarko, L.N. (1974) Role of volatiles. In The Alkaline Rocks, (Sørensen, H., ed.). John Wiley & Sons, London 474-87.Google Scholar
Kogarko, L.N. (1977) Problems of the genesis of agpaitic magmas. Nauka, Moskva, 294 pp, (in Russian).Google Scholar
Kogarko, L.N. and Romanchev, B.P. (1983) Phase equilibria in alkaline melts. lnternat. Geol. Rev., 25, 534-46.CrossRefGoogle Scholar
Konnerup-Madsen, J. and Rose-Hansen, J. (1982) Volatiles associated with alkaline igneous rift activity: fluid inclusions in the Ilímaussaq intrusion and the Gardar granite complexes. Chem. Geol., 37 7993.CrossRefGoogle Scholar
Konnerup-Madsen, J., Kreulen, R. and Rose-Hansen, J. (1988) Stable isotope characteristics of hydrocarbon gases in the alkaline Ilímaussaq complex, south Greenland. Bull. Minéral., 111, 567-76.CrossRefGoogle Scholar
Kostyleva-Labuntsova, E.E., Borutsky, B.E., Sokolova, M.N., Shlyukova, Z.V., Dorfman, M.D., Dudkin, O.B., Kozyreva, L.V. and Ikorskii, S.V. (1978) Mineralogy of Khibina Massif. Nauka, Moskva, vol. 1, 228 pp, vol. 2, 586 pp.Google Scholar
Kramm, U. and Kogarko, L.N. (1994) Nd and Sr isotope signatures of the Khibina and Lovozero agpaitic centres, Kola alkaline province, Russia. Lithos, 32, 225-42.CrossRefGoogle Scholar
Kramm, U., Kogarko, L.N., Kononova, V.A. and Vartiainen, H. (1993) The Kola Alkaline Province of the CIS and Finland: precise Rb-Sr ages define 380—360 Ma age range for all magmatism. Lithos, 30, 3344.CrossRefGoogle Scholar
Krauskopf, K.B. (1961) Übersicht tiber moderne Ansichten zur physikalischen Chemie erzbildender Lösungen. Die Naturwissenschqften, 12, 441—5.CrossRefGoogle Scholar
Kunzendorf, H., Nyegaard, P. and Nielsen, B.L. (1982) Distribution of characteristic elements in the radioactive rocks of the northern part of Kvanefjeld, Ilímaussaq intrusion, South Greenland. Rapp. Grønlands geol. Unders., 109, 132.Google Scholar
Larsen, L.M. (1976) Clinopyroxenes and coexisting mafic minerals from the alkaline Ilímaussaq intru-sion, South Greenland. J. Petrol., 17, 258-90.CrossRefGoogle Scholar
Larsen, L.M. and Sørensen, H. (1987) The Ilímaussaq intrusion - progressive crystallization and formation of layering in an agpaitic magma. In Alkaline Igneous Rocks (Fitton, J.G., and Upton, B.G.J., eds.). Geological Society Special Publication, 30, 473-88.Google Scholar
Le Maitre, R.W. (ed). (1989) A Classification of Igneous Rocks and Glossary of Terms. Blackwell, Oxford, 193 pp.Google Scholar
Lurie, J. (1985) Chemical classification of Pilanesberg rocks. Trans. Geol. Soc. South Africa, 8, 472—3.Google Scholar
Moreau, C., Ohnenstetter, D., Demaiffe, D. and Robineau, B. (1996) The Los Archipelago nepheline syenite ring-structure: a magmatic marker of the evolution of the central and equatorial Atlantic. Canad. Mineral., 34, 281-99.Google Scholar
Nielsen, T.F.D. (1994) Alkaline dike swarms of the Gardiner complex and the origin of ultramafic alkaline complexes. Geoch. lnternat., 31, 37—56.Google Scholar
Paslick, C.R., Halliday, A.N., Davies, G.R., Mezger, K. and Upton, B.G.J. (1993) Timing of Proterozoic magmatism in the Gardar province, southern Greenland. Geol. Soc. Amer. Bull., 105, 272-8.2.3.CO;2>CrossRefGoogle Scholar
Pekov, l.V., Chukanov, N.V., Røinsbo, J. and Sørensen, H. (1997) Erikite - a pseudomorph after vitusite. Neues Jahrb. Mineral., Mh., 97-112.CrossRefGoogle Scholar
Petersen, O.V. and Secher, K. (1993) The Minerals of Greenland. Mineral. Record, 24, pt 2, 165.Google Scholar
Rønsbo, J.G., Leonardsen, E.S., Petersen, O.V. and Johnsen, O. (1983) Second occurrence of vuonne-mite — the llímaussaq alkaline complex, South West Greenland. Neues Jb. Miner., Mh., 451—60.Google Scholar
Saima Deposit Research Group (Chen Zhaobo) (1978) Uranium deposit in the Saima alkaline massif, Northeast China. Sci. Sinica, 21, 365-89.Google Scholar
Schorscher, H.D. and Shea, M.E. (1992) The regional geology of the Polos de Caldas alkaline complex: mineralogy and geochemistry of selected nepheline syenites and phonolites. J. Geochem. Exploration, 45, 25-51.CrossRefGoogle Scholar
Semenov, E.I. (1967) The mineralogical-geochemical types of derivatives of nepheline syenites. The activity of alkalis and volatiles. In Mineralogy of Pegmatites and Hydrothermalites from alkaline Massifs (Tichonenkova, R.P. and Semenov, E.I., eds.). Nauka, Moskva, 52—71, (in Russian).Google Scholar
Semenov, E.I. (1969) The Mineralogy of the Ilímaussaq Massif. Nauka, Moskva, 164 pp, (in Russian).Google Scholar
Semenov, E.I. (1972) Mineralogy of the Lovozero Alkaline Massif. Nauka, Moskva, 307 pp, (in Russian).Google Scholar
Shea, M.E. (1992) Isotopic geochemical characteriza-tion of selected nepheline syenites and phonolites from the Polos de Caldas alkaline complex, Minas Gerais, Brazil. J. Geochem. Exploration, 45, 173-214.CrossRefGoogle Scholar
Sheppard, S.M.F., (1986) Igneous rocks: III: Isotopic case studies of magmatism in Africa, Eurasia and oceanic islands. In Stable Isotopes in High Temperature Geological Processes (Valley, J.W., Taylor, H.P. and O'Neil, J.R., eds). Reviews in Mineralogy, 16, 319-71.Google Scholar
Sokolova, M.N. (1986) Typomorphism ∼f Minerals ∼f Ultraagpaitic Associations. Nauka, Moskva, 118 pp, (in Russian).Google Scholar
Sørensen, E. (1982) Water-soluble substances in Kvanefjeld lujavrite. National Laboratory Risø, Roskilde, 1-4.Google Scholar
Sørensen, H. (1962) On the occurrence of steenstrupine in the llímaussaq massif, Southwest Greenland. Meddel. Grønland, 167, pt. 1, 251 pp.Google Scholar
Sørensen, H. (1974) Alkali syenites, feldspathoidal syenites and related lavas. In The Alkaline Rocks (Sørensen, H., ed.). John Wiley & Sons, London. 2252.Google Scholar
Sørensen, H. (1992) Agpaitic nepheline syenites: a potential source of rare elements. Appl. Geochem.., 7, 417-27.CrossRefGoogle Scholar
Sørensen, H., Hansen, J. and Bondesen, E. (1969) Preliminary account of the geology of the Kvanefjeld area of the llímaussaq intrusion, South Greenland. Rapp. GrCnlands geol. Unders.., 18, 1—40.Google Scholar
Sørensen, H., Rose-Hansen, J., Nielsen, B.L., Løvborg, L., Sørensen, E. and Lundgaard, T. (1974) The uranium deposit at Kvanefjeld, the Ilímaussaq intrusion, South Greenland. Geology, reserves and beneficiation. Rapp. Grønlands geol. Unders., 60, 1-54.Google Scholar
Sørensen, H., Rose-Hansen, J. and Petersen, O. (1981) The mineralogy of the Ilímaussaq intrusion (with a list of all minerals identified up to 1979 and a list of the series “Contributions to the Mineralogy of Ilímaussaq. Rapp. Grønlands geol. Unders., 103, 19-24.Google Scholar
Sørensen, H., Makovicky, M. and Rose-Hansen, J. (1985) Reconnaissance studies on the synthesis and stability of steenstrupine. Bull. Geol. Soc. Finland, 57, 103-12.CrossRefGoogle Scholar
Tuttle, O.F. and Bowen, N.L. (1958) Origin of granite in the light of experimental studies in the system NaAlSi3Os-KAlSi3O8-SiO2-H2O. Geol. Soc. Amer. Memoir, 74, 1-153.CrossRefGoogle Scholar
Ussing, N.V. (1912) Geology of the country around Julianehaab, Greenland. Meddr. Grønland, 38, 1-426.Google Scholar
Varet, J. (1969) Les phonolites agpaïtiques et miaski-tiques du Cantal septentrional (Auvergne, France). Bull. Volcanologique, 33, 621-56.CrossRefGoogle Scholar
Vitrac-Michard, A., Albarède, F. and Azambre, B. (1977) Age Rb-Sr et 39Ar/40 de la syénite néphélinique de Fitou (Corbibres orientales). BulL Soc.fr. Mindral. Cristallogr., 100, 251-4.Google Scholar
Wallace, G.M., Whalen, J.B. and Martin, R.F. (1990) Agpaitic and miaskitic nepheline syenites of the McGerricle plutonic Complex, Gaspé, Quebec: An unusual petrological association. Canad. Mineral., 28, 251-66.Google Scholar
Wolff, J.A. (1987) Crystallization of nepheline syenite in a subvolcanic magma system: Tenerife, Canary Islands. Lithos, 20, 207-23.CrossRefGoogle Scholar
Wolff, J.A. and Toney, J.B. (1993) Trapped liquid from a nepheline syenite: a re-evaluation of Na-, Zr-, F-rich interstitial glass in a xenolith from Tenerife, Canary Islands. Lithos, 29, 285-93.CrossRefGoogle Scholar