Abstract
In early calcite carbonatites of the Kovdor ore deposit four morphological types of dolomite are represented. In the first type, dolomite microcrystals occur as lamellae enclosed by optically continuous calcite. In the second, dolomite microcrystals occur as segmented rods, plates and xenomorphic grains, enclosed by optically discontinuous calcite, and in the third, dolomite is represented by grains of various morphologies, situated along calcite grain boundaries. The fourth type of dolomite occurs as a fine-grained aggregate, which develops along grain boundaries and cleavage cracks of calcite. From microscopic, scanning electron microscope and microprobe studies of these different types of dolomite microcrystals, as well as the calcite associated with them, it can be concluded that the first type of dolomite was exsolved from magnesian calcite during cooling. The second, and the third types of dolomite microcrystals were formed by recrystallization. The fourth type of dolomite was formed by metasomatic dolomitization. As the result of these two processes-recrystallization and metasomatic dolomitization-early dolomite microcrystals seldom occur. The composition of the early-formed primary magnesian calcite yielded temperatures of exsolution of dolomite from magnesian calcite between 665 and 700°C.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Carpenter AB (1967) Mineralogy and petrology of the system CaO−MgO−CO2−H2O at Crestmore, California. Am Mineral 52:1341–1363
Chernyshova EA (1981) Minerals of carbonatites as indicators of conditions of their formation (on the examples of Eastern Siberia massifs) (in Russian). Nauka, Novosibirsk
Goldsmith JR (1983) Phase relations of rhombohedral carbonates. In: Reeder RJ (ed) Carbonates: mineralogy and chemistry. (Reviews in mineralogy 11) Mineral Soc Am, Washington DC, pp 49–76
Grigorev DD (1961) Ontogeny of minerals (in Russian). Lvov Univ, Lvov
Harlamov ES (1978) Inclusions of melts in minerals of iron ores and carbonatites of the Kovdor massif (in Russian). Dokl Akad Nauk SSSR 239:169–172
Kapustin YuL (1971) Mineralogy of carbonatites (in Russian). Nedra, Moscow
Kapustin YuL (1983a) Carbonate correlations in zones of metasomatic dolomitization of carbonatites (in Russian). Dokl Akad Nauk SSSR 268:397–401
Kapustin YuL (1983b) Magnesium metasomatism in early carbonatites (in Russian). Geol Rudn Mestorozhd 25:21–33
Kapustin YuL (1987) Special features of developments of magnesium metasomatism in early calcite carbonatites (in Russian). Zap Vses Mineral Obva 116:28–43
Kopylava LN, Krasnova NI, Martovitskya NA, Poritskya LG (1980) Typochimic special features of calcite and baddeleyite from Kovdor complex deposit (in Russian). In: Egorov LS (ed) Alkaline magmatism and apatite ore rocks of Siberia north. Inst Geol Arctic Region, Leningrad, pp 124–138
Kramm U, Kogarko LN, Kononova VA, 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 30:33–44
Krasnova NI, Kopylova LN (1988) The geologic basis for mineral-technological mapping at the Kovdor ore deposit. Int Geol Rev 30:307–319
Kretz R (1988) SEM study of dolomite microcrystals in Grenville marble. Am Mineral 73:619–631
Powell R, Condliffe DM, Condliffe E (1984) Calcite-dolomite geothermometry in the system CaCO3−MgCO3−FeCO3: an experimental study. J Metamorphic Geol 2:33–41
Puhan D (1976) Metamorphic temperature determined by means of the dolomite-calcite solvus geothermometer-examples from the Central Damara orogen (South West Africa). Contrib Mineral Petrol 58:23–28
Puhan D (1984) Microtexture of dolomite within exsolved magnesian calcite-examples from the Damara orogen (Namibia). Contrib Mineral Petrol 87:98–99
Puustinen K (1974) Dolomite exsolution textures in calcite from the Siilinjarvi carbonatite complex. Finland. Bull Geol Soc Finl 46:151–159
Sidorov APh, Rudashevskii NS (1979) Diagnostic of exolution textures of mineral solid solutions with the help of microprobe analyses (in Russian). Zap Vses Mineral Obva 108:607–616
Talantsev AS (1980) The estimation of the ore-forming systems' depth (in Russian). Dokl Akad Nauk SSSR 250:1212–1215
van der Veen AH (1965) Calcite-dolomite intergrowth in high-temperature carbonate rocks. Am Mineral 50:2070–2076
Zhabin AG (1971) Syngenesis and metamorphism of carbonatites (in Russian). Nauka, Moscow
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Zaitsev, A., Polezhaeva, L. Dolomite-calcite textures in early carbonatites of the Kovdor ore deposit, Kola peninsula, Russia: their genesis and application for calcite-dolomite geothermometry. Contr. Mineral. and Petrol. 115, 339–344 (1994). https://doi.org/10.1007/BF00310772
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00310772