POURBAIX DIAGRAMS AND GEOLOGICAL IMPLICATIONS OF Fe-S-H2O HYDROTHERMAL SYSTEM NEAR 13°N ON THE EAST PACIFIC RISE
-
摘要: 在热力学计算的基础上,依据硫化物中矿物组合和热液流体化学组成绘制东太平洋海隆13°N附近热液Fe-S-H2O系统布拜图(Peurbax diagram),阐明了实际情况下东太平洋海隆13°N附近热液流体由高温至低温的过程中,硫化物中优势矿物黄铁矿的稳定场的演化。结合已有的动力学实验和硫同位素分馏的研究成果,揭示了沉淀硫化物的热液活动过程中形成优势矿物黄铁矿的可能的主要化学反应历程。在东太平洋海隆13°N附近海底热液系统中,热液流体由高温(T>200℃)演化至低温(25~200℃)过程中黄铁矿的形成机制发生了明显的改变。
-
关键词:
- 热液Fe-S-H2O系统 /
- 布拜图 /
- 黄铁矿 /
- 东太平洋海隆13°N
Abstract: Pourbaix diagrams of Fe-S-H2O hydrothermal system near 13°N on the East Pacific Rise were drawn by use of thermodynamic calculations, which illustrated changes of stable fields of predominant mineral (pyrite) in sulfide during changes from high temperatures to low temperatures of hydrothermal fluids which formed the sulfide. Mineral assemblages and chemical compositions were taken into account in computational processes. On the basis of combination with existing research on dynamic experiments and sulfur isotope fractionation, potential chemical reaction pathways which formed the predominant mineral (i.e., pyrite) during marine hydrothermal activities which precipitated sulfides were brought out. Moreover, it is suggested that the formation mechanism of pyrite in the hydrothermal system near 13°N on the East Pacific Rise has changed when hydrothermal fluids which form the sulfide change from high temperatures (>200℃) to low temperatures (25~200℃). -
-
[1] Klitgord K D, Manderickx J. Northern East Pacific Rise:magnetic anomaly and bathymetry framework[J]. Journal of Geophysical Research, 1982, 87(B8):6725-6750.
[2] Francheteau J,Ballard R D. The East Pacific Rise near 21°N, 13°N and 20°N:Inferences for along-strike variability of axial processes of the mid-ocean ridge[J]. Earth and Planetary Science Letters, 1983,64:93-116.
[3] Hékinian R, Fevrier M, Avedik F,et al. East Pacific Rise near 13°N:Geology of new hydrothermal fields[J]. Science, 1983, 219:1321-1324.
[4] Hékinian R, Francheteau J, Renard V,et al. Intense hydrothermal activity at the axis of the East Pacific Rise near 13°N:Submersible witnesses the growth of a sulfide chimney[J]. Marine Geophys.Res., 1983, 6:1-14.
[5] Hékinian R,Fouquet Y. Volcanism and metallogenesis of axial and off-axial structures on the East Pacific Rise near 13°N[J]. Econ. Geol., 1985, 80:221-243.
[6] Gente P, Auzende J M, Renard V,et al. Detailed geological mapping by submersible of the East Pacific Rise axial graben near 13°N[J]. Earth and Planetary Science Letters, 1986, 78:224-236.
[7] Fouquet Y, Aucla G, Cambon P,Etoubleau J. Geological setting and mineralogical and geochemical investigations on sulfide deposits near 13°N on the East Pacific Rise[J]. Marine Geology, 1988, 84(3-4):145-178.
[8] Moss R,Scott S D. Silver in sulfide chimneys and mounds from 13 degrees N and 21 degrees N, East Pacific Rise[J]. Canadian Mineralogist, 1996, 34:697-716.
[9] Fouquet Y, Knott R, Cambon P,et al. Formation of large sulfide mineral deposits along fast spreading ridges:Example from off-axial deposits at 12°43'N on the East Pacific Rise[J]. Earth and Planetary Science Letters, 1996, 144:147-162.
[10] Vink B W. Stability relations of antimony and arsenic compounds in the light of revised and extended Eh-pH diagrams[J]. Chemical Geology, 1996, 130:21-30.
[11] Pichler T, Veizer J. Precipitation of Fe Ⅲ oxyhydroxide deposits from shallow-water hydrothermal fluids in Tutum Bay, Ambitle Island, Papua New Guinea[J]. Chemical Geology, 1999, 162:15-31.
[12] Filella M, Nelson Belzile N, Chen Y W. Antimony in the environment:a review focused on natural waters Ⅱ. Relevant solution chemistry[J]. Earth-Science Reviews, 2002, 59:265-285.
[13] Descostes M, Vitorge P,Beaucaire C. Pyrite dissolution in acidic media[J]. Geochimica et Cosmochimica Acta, 2004, 68(22):4559-4569.
[14] Glynn S, Mills R A, Palmer M R,et al. The role of prokaryotes in supergene alteration of submarine hydrothermal sulfides[J]. Earth and Planetary Science Letters, 2006, 244:170-185.
[15] Christel L,Alexandra N. Energetics of stable and metastable low-temperature iron oxides and oxyhydro xides[J]. Geochimica et Cosmochimica Acta, 1998, 62(17):2905-2913.
[16] Byrne R H,Laurie S H. Influence of pressure on chemical equilibria in aqueous system s-with particular reference to seawater[J]. Pure Appl. Chem., 1999, 71:871-890.
[17] Michard G, Albarede F, Michard A,et al.Chemistry of solutions from the 13°N East Pacific Rise hydrothermal site[J]. Earth and Planetary Science Letters,1984, 67:297-307.
[18] Bowers T S, Campbell A C, Measures C I,et al.Chemical controls on the composition of vent-fluids at 11°~13°N and 21°N, East Pacific Rise[J]. Journal of Geophysical Research, 1988, 93(B5), 4522-4536.
[19] German C R, Colley S, Palmer M R,et al.Hydrothermal plume-particle fluxes at 13°N on the East Pacific Rise[J]. Deep-Sea Research I, 2002, 49:1921-1940.
[20] Majzlan J, Navrotsky A,Schwertmann. Thermodynamics of iron oxides:Part Ⅲ. Enthalpies of formation and stability of ferrihydrite (~Fe(OH)3), schwertmannite (~FeO(OH)3/4(SO4)1/8), and ε-Fe2O3[J]. Geochimica et Cosmochimica Acta, 2004, 68(5):1049-1059.
[21] Beverskog B,Puigdomenech I. Revised pourbaix diagrams for iron at 25~300℃[J]. Corrosion Science, 1996, 38(12):2121-2135.
[22] Kelsall G H,Williams R A. Thermodynamics of Fe-Si-H2O at 298K[J]. J. Electrochem. Soc, 1991, 138:931-940.
[23] Hemingway B S. Thermodynamic properties for bunsenite, NiO, magnetite, Fe3O4, on selected oxygen buffer reactions[J]. Am. Mineral., 1990, 75:781-790.
[24] Silvester E, Charlet L, Tournassat C,et al. Redox potential measurements and Mössbauer spectrometry of FeⅡ adsorbed onto FeⅢ (oxyhydr)oxides[J]. Geochimica et Cosmochimica Acta, 2005, 69(20):4801-4815.
[25] Warner T E, Rice N M, Taylor N. Thermodynamic stability of pentlandite and violarite and new EH-pH diagrams for the iron-nickel sulphur aqueous system[J]. Hydrometallurgy, 1996, 41:107-118.
[26] 傅献彩, 沈文霞, 姚天扬. 物理化学(第四版)[M]. 北京:高等教育出版社, 1990:474-499.[FU Xiancai,SHEN Wenxia,YAO Tianyang. Physical Chemistry(the fourth edition)[M]. Beijing:Advanced Education Publication, 1990:474
-499.]
[27] Taylor D F.Thermodynamic properties of metal-water systems at elevated temperatures[J]. J. Electrochem. Soc., 1978, 125:808-812.
[28] Anderko A,Shuler P J. A computational approach to predicting the formation of iron sulfide species using stability diagrams[J]. Computers & Geosciences,1997, 23(6):647-658.
[29] Rickard D,Luther Ⅲ G W. Kinetics of pyrite formation by the H2S oxidation of iron (Ⅱ) monosulfide in aqueous solutions between 25 and 125℃:The mechanism[J]. Geochimica et Cosmochimica Acta, 1997, 61(1):135-147.
[30] Rickard D. Kinetics of pyrite formation by the H2S oxidation of iron (Ⅱ) monosulfide in aqueous solutions between 25 and 125℃:The rate equation[J]. Geochimica et Cosmochimica Acta, 1997, 61(1):115-134.
[31] Wilkin R T,Barnes H L. Formation processes of framboidal pyrite[J]. Geochimica et Cosmochimica Acta, 1997, 61(2):323-339.
[32] Butler I B, Böttcher M E, Rickard D,et al. Sulfur isotope partitioning during experimental formation of pyrite via the polysulfide and hydrogen sulfide pathways:implications for the interpretation of sedimentary and hydrothermal pyrite isotope records[J]. Earth and Planetary Science Letters, 2004, 228:495-509.
[33] Ono S, Shanks Ⅲ W C, Rouxel O J,et al. S-33 constraints on the seawater sulfate contribution in modern seafloor hydrothermal vent sulfides[J]. Geochimica et Cosmochimica Acta, 2007, 71(5):1170-1182.
-
计量
- 文章访问数: 1089
- PDF下载数: 1
- 施引文献: 0
下载: