Alkaline Rocks and Carbonatites of the World

Kogarko, L. N.; Konova, V. A.; Orlova, M. P.; Woolley, A. R.

doi:10.1007/978-94-011-0513-2

Cited by 31 publications

(46 citation statements)

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“…The UACC are multiphase central intrusions with circular or elliptical exposures and concentrically zoned structures (Kukharenko et al, 1965;Kogarko et al, 1995). Their centres contain a series of ultramafic cumulus rocks, whereas melilite-bearing rocks and strongly silicaundersaturated feldspathoidal rocks (foidolites) occur nearer to the periphery.…”

Section: Ultramafic-alkaline Carbonatite Complexes (Uacc)mentioning

confidence: 99%

“…The province is well-known for its ultramafic, alkaline and carbonatite magmatism (Kogarko, 1987;Woolley, 1989;Arzamastsev, 1994;Kogarko et al, 1995;Bulakh et al, in press). It consists of nineteen alkaline-ultramafic rock complexes, most of which also contain carbonatites, together with two giant nepheline syenite complexes (Lovozero and Khibiny) and numerous dykes and pipes of various ultramafic and evolved alkaline rocks, kimberlites and carbonatites.…”

Section: Introductionmentioning

confidence: 99%

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Petrogenetic processes in the ultramafic, alkaline and carbonatitic magmatism in the Kola Alkaline Province: A review

Downes

Balaganskaya

Beard

et al. 2005

Lithos

172

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Igneous rocks of the Devonian Kola Alkaline Carbonatite Province (KACP) in NW Russia and eastern Finland can be classified into four groups: (a) primitive mantle-derived silicaundersaturated silicate magmas; (b) evolved alkaline and nepheline syenites; (c) cumulate rocks; (d) carbonatites and phoscorites, some of which may also be cumulates. There is no obvious age difference between these various groups, so all of the magma-types were formed at the same time in a relatively restricted area and must therefore be petrogenetically related. Both sodic and potassic varieties of primitive silicate magmas are present. On major element variation diagrams, the cumulate rocks plot as simple mixtures of their constituent minerals (olivine, clinopyroxene, calcite etc). There are complete compositional trends between carbonatites, phoscorites and silicate cumulates, which suggests that many carbonatites and phoscorites are also cumulates. CaO/Al 2 O 3 ratios for ultramafic and mafic silicate rocks in dykes and pipes range up to 5, indicating a very small degree of melting of a carbonated mantle at depth. Damkjernites appear to be transitional to carbonatites. Trace element modelling indicates that all the mafic silicate magmas are related to small degrees of melting of a metasomatised garnet peridotite source. Similarities of the REE patterns and initial Sr and Nd isotope compositions for ultramafic alkaline silicate rocks and carbonatites indicate that there is a strong relationship between the two magma-types. There is also a strong petrogenetic link between carbonatites, kimberlites and alkaline ultramafic lamprophyres. Fractional crystallisation of olivine, diopside, melilite and nepheline gave rise to the evolved nepheline syenites, and formed the ultramafic cumulates. All magmas in the KACP appear to have originated in a single event, possibly triggered by the arrival of hot material (mantle plume?) beneath the Archaean/Proterozoic lithosphere of the northern Baltic Shield that had been recently metasomatised. Melting of the carbonated garnet peridotite mantle formed a spectrum of magmas including carbonatite, damkjernite, melilitite, melanephelinite and ultramafic lamprophyre. Pockets of phlogopite metasomatised lithospheric mantle also melted to form potassic magmas including kimberlite. Depth of melting, degree of melting and presence of metasomatic phases are probably the major factors controlling the precise composition of the primary melts formed.

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Section: Ultramafic-alkaline Carbonatite Complexes (Uacc)mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Petrogenetic processes in the ultramafic, alkaline and carbonatitic magmatism in the Kola Alkaline Province: A review

Downes

Balaganskaya

Beard

et al. 2005

Lithos

172

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“…The majority, including the economically most important ones, formed in the Paleozoic but there are also several older generations reaching into the Paleoproterozoic and the Neoarchean [1][2][3][4][5][6][7][8]. Al- * E-mail: fernando.corfu@geo.uio.no kalic complexes witness episodes of mantle activity, generally related to extensional tectonic processes in the crust [e.g.…”

Section: Introductionmentioning

confidence: 99%

U-Pb ID-TIMS age of the Tiksheozero carbonatite: expression of 2.0 Ga alkaline magmatism in Karelia, Russia

et al. 2011

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Abstract:The Tiksheozero carbonatite in northern Russian Karelia is a transitional type between alkaline ultramafic -carbonatitic and alkaline gabbroic suites. The complex is dominated by pyroxenite with a variety of subordinate mafic and ultramafic phases and nepheline syenite. Carbonatite occurs in a main central body and in veins. In this study we have obtained a reliable age for the complex by single grain ID-TIMS U-Pb analyses of zircon and baddeleyite. The age of 1999 ± 5 Ma is important because it places the emplacement of the alkaline complexes in the context of craton-wide extension and break-up events which preceded the initiation of a major Paleoproterozoic orogenic cycle. The Paleoproterozoic age also emphasizes the fact that not all members of the Kola alkaline province are of Paleozoic age.

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“…1), occupying an area of less than 35 km 2 (Egorov 1991;Kogarko et al 1995 and references cited therein), are present.…”

Section: Geological Background and Sample Locationmentioning

confidence: 99%

Native osmium from the Guli Massif, Northern Siberia, Russia

et al. 2011

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SummaryNative osmium from two different placer occurrences (i.e., Ingaringda and Burlakovsky) within the Guli Massif, Maimecha-Kotui Province, was evaluated for mineral compositions that show systematic differences between the localities. Grains of native osmium show increases in iridium towards the rim, and nuggets consisting of aggregates define trends of preferential substitution of osmium by iridium. A statistically reliable difference in Os/Ir ratios between the two studied placers can be demonstrated. From textural and compositional characteristics it is concluded that the native osmium of the Burlakovsky placer formed at temperatures higher than can be assumed to be reasonable for crustal conditions. The difference in the Os/Ir ratios between the two placers can be attributed to fractional crystallization of native osmium either in the mantle source, which was tapped in different events to form the Guli Massif, or to decreasing Os/Ir values during crystallization under crustal conditions after intrusion of the silicate melt(s).

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Alkaline Rocks and Carbonatites of the World

Cited by 31 publications

References 0 publications

Petrogenetic processes in the ultramafic, alkaline and carbonatitic magmatism in the Kola Alkaline Province: A review

Petrogenetic processes in the ultramafic, alkaline and carbonatitic magmatism in the Kola Alkaline Province: A review

U-Pb ID-TIMS age of the Tiksheozero carbonatite: expression of 2.0 Ga alkaline magmatism in Karelia, Russia

Native osmium from the Guli Massif, Northern Siberia, Russia

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