冲绳海槽中部Jade热液活动区中海底热液沉积物的硫同位素组成及其地质意义
Sulfur isotopic composition of seafloor hydrothermal sediment from the Jade hydrothermal field in the central Okinawa Trough and its geological significance
-
摘要: 测定了冲绳海槽中部Jade热液活动区中18个热液沉积物样品的硫同位素组式,其中10个硫化物样品的δ34S值为5.2×10-3~7.2×10-3,7个硫酸盐样品的34S值为16.3×10-3~22.3×10-3,1个自然硫样品的δ34S值为8.2×10-3热液沉积物的硫主要来自中、酸性火山岩和海水,并且在流体与沉积物相互作用过程中海底沉积物也可能为热液沉积物的形成提供部分的硫.导致本区热液沉积物中硫化物与其他热液活动区的硫同位素组成不同的原因,主要是各热液活动区的硫源以及有关岩浆活动和构造演变的不同.海底热液体系中硫的演化是一个复杂的过程,涉及被加热海水的上升、流体与火山岩的相互作用、海水硫酸盐和中、酸性火山岩中流的混合作用以及流体与沉积物相互作周等一系列海底热液活动,其中海水和中、酸性火山岩的相互作用是本区硫演化的一个重要机制.Abstract: Eighteen samples of h州rothermal sediments from the Jade hydrothermal field in the central Okinawa Trough have been analyzed.Sulfur isotopic values for 10 sulfide samples vary from 5.2×10-3 to 7.2×10-3, δ34S values for 7 sulfate samples vary from 16.3×10-3 to 22.3×10-3, and δ34S value for 1 native sulphur sample is 8.2×10-3.The major sources of sulfur for hydrothermal sediment are intermediate to acid volcanic rocks and seawater sulfate, and it is possible that the partial sulfur of hydrothermal sediment is from the pelagic sediment by the interaction between hydrothermal fluid and sediment.The、of causing the distinct differences in sulfur isotope values for sulfide samples from hydrothermal sediment(compared with other hydrothermal fields), are the differences in the sources of sulfur, the magmatic activity and the tectonic evolution in different hydrothermal fieds.The sulfur evolution is a long and complex process in the seafloor hydrothermal system, involving the ascending of heating seawater, the interaction between fluid and volcanic rocks, the mixing of seawater sulfate and sulfur from intermediate to acid volcanic rocks, and the fluid/pelagic-sediment interaction.And the interaction between seawater and intermediate to acid volcanic rocks is a important mechanism for the sulfur evolution in the Jade hydrothetmal field.
-
Letouzey J, Kimura M. Okinawa Trough genesis:structure and evolution of a back-arc basin developed in a continent. Marine-and Petroleum Geology, 1985, 2:111~130 Sibuet J C, Letouzey J, Barbier F, et al. Back-arc extension in the Okinawa Trough. J Geophys Res, 1987, 92:14 041~14063 Halbach P, Pracejus B, Maiten A, et al. Geology and mineralogy of massive sulfide ores from the central Okinawa Trough. Japan Econ Geol, 1993, 88:2 210~2 225 Halbach P, Nakamura K, Wahsner M, et al. Probable modem analogue of kuroko-type massive sulphide deposits in the Okinawa Trough back-arc basin. Nature, 1989, 338:496~499 Sakai H, Gamo T, Kim E-S, et al. Venting of carbon dioxide-rich fluid and hydrate formation in mid-Okinawa Trough backarc basin. Science, 1990, 248:1 093~1 096 Sakai H, Gamo T, Kim E-S, et al. Unique chemistry of the hydrothermal solution in the mid-Okinawa Trough backarc basin. Geophys Res Lett, 1990, 17:2 133~2 136 侯增谦,张绮玲.冲绳海槽现代活动热水区CO2-烃类流体:流体包裹体证据.中国科学(D辑),1998,28:142 148 Kinoshita M, Yamano M. Hydrothermal regime and constraints on reservoir depth of the Jade site in the mid-Okinawa Trough inferred from heat flow measurements. J Geophys Res, 1997, 102(B2):3 183~3 194 Hawkins J W, Melchior J T. Petrology of Mariana Trough and Lau Basin basalts. J Geophys Res, 1985, 90:11 431~11 468 Ueda A, Sakai H. Sulfur isotope study of Quaternary volcanic rocks from the Japanese island arc. Geochim Cosmochim Acta, 1984, 48:1 837~1 848 Woodhead J D, Harmon R S, Fraser D G, et al. O, S, Sr and Pb isotope variations in volcanic rocks from the northern Mariana Islands:implications for crustal recycling in intra-oceanic arcs. Earth Planet Sci Lett, 1987, 83:39~52 Sakai H, DesMarais D J, Ueda A, et al. Concentrations and isotope ratios of carbon, nitrogen and sulfur in ocean-floor basalts. Geochim Cosmochim Acta, 1984, 48:2 433~2 441 李巍然,杨作升,王永吉等.冲绳海槽火山岩岩石化学特征及其地质意义.岩石学报,1997,13:538~550 Rees C E, Jenkins W J, Monster J, et al. The sulfur isotopic composition of ocean water sulfate. Geochim Cosmochim Acta, 1978, 42:377~381 根建心具,上野宏共,小坂丈予ほか冲绳卜テア南奄西海丘の海度热水矿床-特に构成矿物について一.第8回しんかいシンポシワ厶报告书.1992.95~106 Kusakabe M, Mayedn S, Nakamara E, et al. S, O and Sr isotope systematics of active vent materials from the Mariana backarc basin spreading axis at 18°N. Earth Planet Sci Lett, 1990, 100:275~282 Herzig P M, Hannington M D, Arribas A Jr, et al. Sulfur isotopic composition of hydrothermal precipitates from the Lau back-arc:implications for magmatic contributions to seafloor hydrothermal systems. Mineralium Deposita, 1998, 33:226~237 Peter J M, Shanks Ⅲ W C. Sulfur, carbon, and oxygen isotope variations in submarine hydrothermal deposits of Guaymas Basin, Gulf of California, U S A. Geochim Cosmochim Acta, 1992, 56:2 025~2 040 Shanks W C Ⅲ, Seyfried W E Jr. Stable isotope studies of vent fluids and chimney minerals, southern Juan de Fuca Ridge:sodium metasomatism and seawater sulfate reduction. J Geophys Res, 1987, 92:11 387~11 399 Woodruff L G, Shanks W C. Sulfur isotope study of chimney minerals and hydrothermal fluids from 21°N, East Pacific Rise:hydrothermal sulfur sources and disequilibrium sulfate reduction. J Geophys Res, 1988, 93:4 562~4 572 Gamo T, Sakai H, Kim E-S, et al. High alkalinity due to sulfate reduction in the Clam hydrothermal field, Okinawa Trough. Earth Planet Sci Lett, 1991, 107:328~338 Bowers T S. Stable isotope signatures of water-rock interaction in mid-ocean ridge hydrothermal systems:sulfur, oxygen, and hydrogen. J Geophys Res, 1989, 94:5 775~5 786 郑永飞,傅斌,张学华岩浆去气作用的碳硫同位素效应.地质科学,1996,31:43~53 Marty B, Jambon A, Sano Y, et al. Helium isotopes and CO2 in volcanic gases of Japan. Chem Geol, 1989, 76:25~40
点击查看大图
计量
- 文章访问数: 860
- HTML全文浏览量: 19
- PDF下载量: 1236
- 被引次数: 0