Kigay I.N.
Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry RAS (IGEM RAS)
Language: Russian
Geochemistry and ore formation 2012, 31-32: 56-66
https://doi.org/10.15407/gof.2012.31.056
Acidity evolution of magmatic fluids is determined by dependence of dissociation constants of hydrolysis products of alkali metal chlorides on temperature and pressure. High-temperature supercritical fluids, derived from granitic melts are initially alkaline. Being cooled they can become acidic. But fluid’s acidity sufficient for creation of acidic metasomatites is not a consequence of simple cooling of initially alkaline fluids or of an overtaking wave of acidic components suggested by D.S. Korzhinskii, – it is a result of acid gases’ condensation at the upper parts of closed heterophase subcritical fluid systems. This conclusion is based on silica loss from all silicate host rocks during acidic leaching (greisening, tourmalinization etc.), as well as on close relation of acidic metasomatites with filling veins and fluids’ heterogenization. All types of alkaline and acidic metasomatites formation are characterized by formation of monomineral rear zones containing no quartz; these are the K-feldspar, albite or chlorite zones in alkaline metasomatites and the topaz, muscovite, tourmaline and sericite zones in acidic ones. During a multistage mineralization, any stage of mineralization is started from formation of near-fracture metasomatic column and is terminated with precipitation of ore minerals and redeposition of previously leached silica to form quartz in veins and in altered host rocks up to formation of monomineral rear quartz zones. The latter are always secondary relative to other monomineral zones. General evolution of fluid’s acidity starts from subneutral fluids through high-temperature alkaline ones to acidic fluids and finally to vertically separated low-temperature acidic and alkaline fluids. This succession is rather similar to that of D.S. Korzhinskii’s “overtaking acidity wave”, but is instead a multiple multistage repetition of both alkaline metasomatism and acidic leaching with the conjugated ore assemblages. A group of mineral deposits, whose ore mineralization is related to preore acidic metasomatism and forms with the participation of heterophase fluids, comprises practically all postcollisional W, Sn, Be, Li veintype deposits genetically related to reduced calc-alkaline granitoids, and Au, Ag, Cu, Pb, Zn, As, Sb, and Hg deposits genetically related to oxidized basic magmatites of mantle origin.
References
1. Balickij V.S i Zubkova E.I. Akkumulyaciya kremnezema v gidrotermalnyh rastvorah. Gidrotermalnye mineraloobrazuyushie rastvory oblastej aktivnogo vulkanizma, Novosibirsk: Nauka, 1974, pp. 114–119.
2.Borodaevskij N.I., Borodaevskaya M.B. Beryozovskoe rudnoe pole (geologicheskoe stroenie), Metallurg. izdat., 1947, 264 p.
3. Bryzgalin O.V. Nekotorye silnye elektrolity v nadkriticheskoj oblasti (ocenka konstant dissociacii na osnove elektrostaticheskoj modeli). Geohimiya, 1985, No 8, pp. 1184–1195.
4. Govorov I.N. Redkometalnye grejzeny v karbonatnyh porodah. Geohimiya, mineralogiya i geneticheskie tipy mestorozhdenij redkih elementov, T. 3, Nauka, 1966, pp. 156–184.
5. Zharikov V.A., Zarajskij G.P. Eksperimentalnoe issledovanie metasomatizma: sostoyanie, perspektivy. Geologiya rudn. mestorozhdenij, 1973, T. 15, No 4, pp. 3–18.
6. Zharikov V.A., Omelyanenko B.I. Nekotorye problemy izucheniya izmenenij vmeshayushih porod v svyazi s metalogenicheskimi issledovaniyami. Izuchenie zakonomernostej razmesheniya mineralizacii pri metallogenicheskih issledovaniyah rudnyh rajonov, Nedra, 1965, pp. 119–194.
7. Kigaj I.N. Lifudzinskoe olovorudnoe mestorozhdenie i nekotorye voprosy gidrotermalnogo mineralo-obrazovaniya, Nauka, 1966, 248 p.
8. Kigaj I.N. O pulsacionnoj teorii i kriteriyah stadijnosti gidrotermalnogo mineraloobrazovaniya. Zonalnost gidrotermalnyh rudnyh mestorozhdenij, T. 2, Nauka, 1974, pp. 164–195.
9. Kigaj I.N. Model mnogostadijnogo mineraloobrazovaniya, soglasuyushayasya s variaciyami osnovnyh pa ra metrov gidrotermalnogo processa. Osnovnye parametry prirodnyh processov endogennogo rudoobrazovaniya. Novosibirsk: Nauka, 1979, T. 2, pp. 7–34.
10. Kigaj I.N. Genezis gidrotermalnyh mestorozhdenij cvetnyh i redkih metallov, svyazannyh s granitami. Dokt. diss. v forme nauchnogo doklada (geol.-min. nauk.), IGEM, 1989, 46 p.
11. Kigaj I.N. Redoks-problemy “Metallogenicheskoj specializacii” magmatitov i gidrotermalnogo rudoobrazovaniya. Petrologiya, 2011, T. 19, No 3, pp. 316–334.
12. Kigaj I.N., Nikolaev S.V. O vliyanii fizicheskih svojstv gidrotermalno izmenennyh porod na metasomaticheskoe rudootlozhenie. Geologiya rudn. mestorozhdenij, 1965, No 2, pp. 25–37.
13. Kigaj I.N., Samovarov Yu.V. Mineraloobrazovanie pri uchastii geterofaznyh flyuidov na primere olovo rudnogo mestorozhdeniya Trudovoe v Kirgizii. Zap. VMO, 1989, Vyp. 2, pp. 8–24.
14. Kigaj I.N., Tagirov B.R. Evolyuciya kislotnosti rudoobrazuyushih flyuidov, obuslovlennaya gidrolizom hloridov. Petrologiya, 2010, T. 18, No 3, pp. 270–281.
15. Korzhinskij D.S. Ocherk metasomaticheskih processov. Osnovnye problemy v uchenii o magmatogennyh rudnyh mestorozhdeniyah, Izd-vo AN SSSR, 1953, pp. 332–452.
16. Korzhinskij D.S. Gidrotermalnaya kislotno-shelochnaya differenciaciya. Dokl. AN SSSR, 1958, T. 122, No 2, pp. 267–270.
17. Korzhinskij D.S. Teoriya metasomaticheskoj zonalnosti, 1-e izd, Nauka, 1969, 112 p.
18. Korzhinskij D.S. Teoriya metasomaticheskoj zonalnosti, 2-e izd, Nauka, 1982, 104 p.
19. Levickij O.D. Volframovye mestorozhdeniya Vostochnogo Zabajkalya. Mestorozhdeniya redkih i malyh metallov SSSR, T. II, Izd-vo AN SSSR, 1939, 271 p.
20. Metasomatity i metasomaticheskie porody / Pod red. V.A. Zharikova, V.L. Rusinova, Nauch. mir, 1998, 490 p.
21. Melentev B.N., Ivanenko V.V., Pamfilova L.A. Rastvorimost nekotoryh rudoobrazuyushih sulfidov v gidrotermalnyh usloviyah, Nauka, 1968, 104 p.
22. Nakovnik N.I. Opredelenie kolichestvennogo izmeneniya veshestva pri gidrotermalnom metamorfizme. Zap. VMO, 1958, Vyp. 4, pp. 401–417.
23. Naumov V.B., Kovalenko V.I., Dorofeeva V.A. i dr. Srednij sostav magmaticheskih rasplavov glavnyh geodina micheskih obstanovok po dannym izucheniya rasplavnyh vklyuchenij v mineralah i zakalochnyh styokol porod. Geohimiya, 2010, No 12, pp. 1266–1288.
24. Naumov G.B., Dorofeeva V.A. Himicheskaya priroda evolyucii kislotnosti endogennyh rastvorov. Geohimiya. 1975, No 2, pp. 248–258.
25. Rafalskij R.P. K probleme kislotnosti gidrotermalnyh rastvorov. Geohimiya, 1987, No 3, pp. 402–415.
26. Rejf F.G. Rudoobrazuyushij potencial granitov i usloviya ego realizacii, Nauka. 1990, 181 p.
27. Styrikovich M.A. Issledovanie rastvorimosti maloletuchih soedinenij v vodyanom pare vysokogo davleniya. Termodinamika i stroenie rastvorov, Izd-vo AN SSSR, 1959, pp. 158–166.
28. Sherban I.P. Usloviya obrazovaniya nizkotemperaturnyh okolorudnyh metasomatitov (na primere Altae-
Sayanskoj oblasti), Novosibirsk: Nauka, 1975, 200 p.
29. Bowers T.S., Helgeson H.C. Calculation of the thermodynamic and geochemical consequences of nonideal mixing in the system H2O–CO2–NaCl on phase relations in geologic systems: Equation of state for H2O–CO2–NaCl fluids at high pressures and temperatures. Geochim. Cosmochim. Acta, 1983, V. 47, No 7, pp. 1247–1275. https://doi.org/10.1016/0016-7037(83)90066-2
30. Bussink R.W., Kreulen R & DeIong A.F.M. Gas analyses, fluid inclusion and stable isotopes of the Panasqueira W-Sn deposits, Portugal. Bulletin de Minеralogie. –1984, Vol. 107, No 6, pp. 703–713. https://doi.org/10.3406/bulmi.1984.7813
31. Drummond S.E., Ohmoto H. Chemical evolution and mineral deposition in boiling hydrothermal system. Econ. Geol. 1985, V. 80, No 1, pp. 126–147. https://doi.org/10.2113/gsecongeo.80.1.126
32. Franck E.U. Hochverdichteter wasserdampf. III. Ionendissoziation von KCl, KOH und H2O in ьberkritischen Wasser. Z. Phys. Chem. N.F, 1956, B. 8, pp. 192–206. https://doi.org/10.1524/zpch.1956.8.3_4.192
33. Gehrig M. Phasengleichgewichte und PVT_Daten ternarer Mischungen aus Wasser, Kohlen-dioxid und Natriumchlorid bis 3 kbar und 550°C. University of Karlsruhe, doct. Dissert. Hoch-schulSammlung Naturwissenschaft, Chemie. 1980, B. 1, Freiburg: HochschulVerlag, 1980, 104 p.
34. Jackson K.J. &, Helgeson H.C. Chemical and thermodynamic constraints on the hydrothermal transport and deposition of tin. I. Calculation of solubility of cassiterite at high pressures and tem-peratures. Geoch. et Cosmochim. Acta, 1985. Vol. 79, No 1, pp. 1–22. https://doi.org/10.1016/0016-7037(85)90187-5
35. Kelly W.C., Turneaure F.C. Mineralogy, paragenesis and geothermometry of the tin and tungsten deposits of the Eastern Andes, Bolivia. Econ. Geol, 1970, V. 65, No 6, pp. 609–680. https://doi.org/10.2113/gsecongeo.65.6.609
36. Kelly W.C., Rye R.O. Geologic, fluid inclusion, and stable isotope studies of the tin-tungsten deposits of Panasqueira, Portugal. Econ. Geol, 1979, V. 74, No 8, pp. 1721–1822. https://doi.org/10.2113/gsecongeo.74.8.1721
37. Kigai I.N. Two hydrodynamic types of ore forming systems. Metallization associated with acid magmatism, Prague, 1978, V. 3, pp. 343–348.
38. Lindgren, W. Volume changes in metamorphism. Jour. of Geol, 1918, Vol. 26, No6, pp. 542–554. https://doi.org/10.1086/622615
39. Lindgren, W. Metasomatism. Bull. Geol. Soc. Amer, 1925, Vol. 36, No 1, pp. 247–262. https://doi.org/10.1130/GSAB-36-247
40. Roedder E. Fluid inclusion studies of the porphyry type ore deposits at Bingham, Utah, Butte, Montana, and Climax, Colorado. Econ. Geol, 1971, V. 66, No 1, pp. 98–120. https://doi.org/10.2113/gsecongeo.66.1.98
41. Roedder E. Composition of fluid inclusions. U.S. Geol. Surv. Prof, Paper 440_JJ, 1972, 164 p. https://doi.org/10.3133/pp440JJ
42. Roedder E. Fluid inclusions. Mineral. Soc. Amer. Rev. Mineral, 1984, V. 12, 644 p. https://doi.org/10.1515/9781501508271
43. Roedder E., Bodnar R.J. Fluid inclusion studies of hydrothermal ore deposits. Geochemistry of Hydrothermal Ore Deposits / Ed. H.L. Barnes ; 3rd ed. J, London: Wiley and Sons, 1997, pp. 657–697.
44. White D.E., Muffler, L.J.P., Truesdell A.H. Vapor-dominated hydrothermal systems compared with hot-water systems. Econ. Geol, 1971, V. 66, No 1, pp. 75–97. https://doi.org/10.2113/gsecongeo.66.1.75
45. Wyllie P.J. Experimental petrology of subduction, andesites, and batholiths. Trans. Geol. Soc. of South Africa. 1981, V. 84, Pt. 3, pp. 281–291.
46. Wyllie P.J., Huang W.L., Stern C.R., & Maalшe S. Granitic magmas: possible and impossible sources, water contents and crystallization sequences. Canad. J. Earth Sci, 1976, V. 13, No. 8, pp. 1007–1020. https://doi.org/10.1139/e76-104
Download (PDF)