上地幔Os同位素组成的演化

支霞臣; 秦协

上地幔Os同位素组成的演化

支霞臣,
秦协

中国科学院壳幔物质和环境重点实验室中国科学技术大学地球和空间科学学院安徽合肥 230026

基金项目:

国家自然科学基金项目 40473008

国家自然科学基金项目 40572036

详细信息

作者简介:
支霞臣(1942-), 男, 教授, 地球化学专业.E-mail: xczhi@ustc.edu.cn

中图分类号: P588.12
计量
- 文章访问数: 4012
- HTML全文浏览量: 489
- PDF下载量: 16
- 被引次数: 0
出版历程
- 收稿日期: 2005-10-23
- 刊出日期: 2006-01-25

Evolution of Os Isotopic Compositions in the Upper Mantle

摘要

摘要: Re-Os同位素体系为研究地幔的成分-结构-演化提供了新的地球化学示踪和定年的工具.上地幔Os同位素组成演化的球粒陨石模型是Re-Os体系用于地幔物质定年的基础, 尤其在采用Re亏损模式年龄和Os同位素代理等时线年龄时.综合了铁陨石和各类球粒陨石、地幔橄榄岩包体和蛇绿岩豆荚状铬铁矿的Re-Os同位素体系研究的近期成果, 为认识对流上地幔Os同位素组成的演化提供了制约.对河北遵化蛇绿岩豆荚状铬铁矿岩的研究, 获得新太古代(2.5 Ga)时形成豆荚状铬铁矿的对流上地幔的¹⁸⁷Os/¹⁸⁸Os=0.110 2, 与球粒陨石型模式的一致.文献中常用的球粒陨石模式的参数如下: 地球形成时(4.558 Ga)初始值¹⁸⁷Os/¹⁸⁶Os为0.095 31, 现代值分别采用碳质球粒陨石的¹⁸⁷Os/¹⁸⁶Os比值为0.127 0和原始上地幔(PUM)的¹⁸⁷Os/¹⁸⁶Os比值为0.129 6, PUM与普通球粒陨石和顽火球粒陨石的¹⁸⁷Os/¹⁸⁶Os比值接近.
- 对流上地幔 /
- Re-Os同位素体系 /
- 球粒陨石型 /
- 蛇绿岩豆荚状铬铁矿 /
- 地幔橄榄岩包体
Abstract: The Re-Os isotope system is a new technique of geochemical dating and tracing, specially in the basic subject of the composition-structure-evolution of the earth's mantle. The chondritic model of the evolution of Os isotope compositions in the upper mantle is the important background of Re-Os isotope dating for the mantle-derived materials, especially using Re depleted model age and Os proxy isochron methods. The comprehensive studies of various meteorites, mantle-derived peri-dotitic xenoliths and ophiolitic podiform chromites offered strong constraints on the evolution of Os isotope compositions in the convective upper mantle. We offer the Os isotope composition of convective upper mantle in the Late Archean, based on ophiolitic podiform chromitites from Zunhua, Hebei Province, which is 0. 110 2. This is consistent with the chondritic model. The parameters of the chondrite model in common use are: the initial osmium isotope ratio is 0. 095 31 at 4. 558 Ga; the present osmium isotope ratios are 0. 127 0 of carbonaceous chondrite and 0. 129 6 of the primitive upper mantle respectively. The latter is similar to that of ordinary and enstatite chondrites.
- convective upper mantle /
- Re-Os isotopes /
- chondritic model /
- ophiolitic podiform chromites /
- mantle xenoliths

HTML全文

图 1 3类球粒陨石的Re-Os同位素体系与ⅢAB组铁陨石的比较(Walker et al., 2002)

Fig. 1. Comparison of Re-Os isotope system between vari-ous chondrites andⅢAB irons

下载: 全尺寸图片幻灯片

图 2 原始上地幔和球粒陨石的Os同位素组成(Walker et al., 2002)

Fig. 2. Comparison of Os isotopic compositions between PUM and chondrites

下载: 全尺寸图片幻灯片

图 3 由蛇绿岩豆荚状铬铁矿岩和铬铁矿获得的对流上地幔Os同位素组成的演化

Fig. 3. Evolution of Os isotope compositions in convective upper mantle derived from ophiolitic podiform chromitites and chromites

下载: 全尺寸图片幻灯片

图 4 蛇绿岩豆荚状铬铁矿和铬铁矿岩的Re-Os元素丰度

Fig. 4. Re and Os abundances of ophiolitic podiform chromi tites and chromites

下载: 全尺寸图片幻灯片

图 5 河北遵化新太古代蛇绿岩豆荚状铬铁矿岩和铬铁矿的Re-Os同位素体系

Fig. 5. Re-Os isotope systematics of Late Archean ophiolitic podiform chromitites and chromites from Zunhua, Hebei Province

下载: 全尺寸图片幻灯片

表 1 铁陨石的Re-Os年龄和Os同位素初始值(Cook et al., 2004)

Table 1. Re-Os isotope age and initial ratio of various irons

表 2 球粒陨石的Re-Os同位素体系(Walker et al., 2002)

Table 2. Re-Os isotope system of various chondrites

参考文献(36)

Alard, O., Luguet, A., Pearson, N. J., et al., 2005. In situ Os isotopes in abyssal peridotites bridge the isotopic gap between MORE and their source. Nature, 436: 1005-1008. doi: 10.1038/nature03902
Allegre, C. J., Luck, J. M., 1980. Osmium isotopes as petro-genetical traces. Earth Planet. Sci. Lett., 48: 148 - 154. doi: 10.1016/0012-821X(80)90177-6
Becker, H., Morgan, J. W., Walker, R. J., et al., 2001. Rhenium-osmium systematics of calcium-aluminum-rich inclusions in carbonaceous chondrites. Geochim. Cosmo-chim. Acta, 65: 3379-3390. doi: 10.1016/S0016-7037(01)00676-7
Bennett, V. C., 2004. Compositional evolution of the mantle. In: Holland, H. D., Turekian, K. K., eds., Treatise of Geochemistry, 2. Elsevier-Pergamon, Oxford, 493-519.
Birck, J. L., Allegre, C. J., 1994. Contrasting Re/Os mag-matic fractionation in planetary basalts. Earth Planet. Sci. Lett., 124: 139-148. doi: 10.1016/0012-821X(94)00086-7
Carlson, R W., 2005. Application of the Pt-Re-Os isotopic systems to mantle geochemistry and geochronology. Lithos, 82: 249-272. doi: 10.1016/j.lithos.2004.08.003
Chen, J. H., Papanastassiou, D. A., Wasserburg, G. J., 1998. Re-Os systematics in chondrities and the fractionation of the platinum group elements in the early solar system. Geochim. Cosmochim. Acta, 62 (19/20): 3379 -3392.
Chen, J. H., Papanastassiou, D. A., Wasserburg, G. J., 2002. Re-Os and Pd-Ag systematics in group Ⅲ AB iron and in pallasites. Geochim. Cosmochim. Acta, 66(21): 3793-3810. doi: 10.1016/S0016-7037(02)00952-3
Cook, D. L., Walker, R. J., Horan, M. F., et al., 2004. Pt-Re-Os systematics of group Ⅱ AB and Ⅲ AB iron meteorites. Geochim. Cosmochim. Acta, 68(6): 1413-1431. doi: 10.1016/j.gca.2003.09.017
Foster, J. G., Lambert, D. D., Frick, L. R., et al., 1996. Re-Os isotopic evidence for genesis of Archean nickel ores from uncontaminated komatiites. Nature, 382: 703 - 706. doi: 10.1038/382703a0
Gornostayev, S. S., Walker, R. J., Hanski, E. J., et al., 2004. Evidence for the emplacement of ca. 3.0 Ga mantle-derived mafic bodies in the Ukrainian Shield. Precambrian Research, 132: 349 - 362.
Krot, A, N., Keil, K., Goodrich, C. A., et al., 2004. Classification of meteorites. In: Holland, H. D., Turekian, K. K., eds., Treatise of geochemistry, 1. Elsevier-Perga-mon, Oxford, 83-128.
Kusky, T. M., Li, J. H., Raharimahefa, T., et al., 2004. Re-Os isotope chemistry and geochronology of chromite from mantle podiform chromitites from the Zunhua ophiolitic meloge belt, NW China: Correlation with the Dongwanzi ophiolite. In: Kusky, T. M., ed. Precambrian ophiolites and related rocks. Elsevier, 275-282.
Luck, J. M., Alleger, C. J., 1983. ¹⁸⁷ Re^-188 Os systematics in meteorites and cosmochemical consequences. Nature, 302: 130-132 doi: 10.1038/302130a0
Luck, J. M., Birck, J. L., Alleger, C. J., 1980. ¹⁸⁷Re^-188Os systematics in meteorites: Early chronology of the solar system and age of the galaxy. Nature, 283: 256-259. doi: 10.1038/283256a0
McDonough, 2004. Compositional model for the earth's core. In: Holland, H. D., Turekian, K. K., eds., Treatise of geochemistry, 2. Elsevier-Pergamon, Oxford, 547-568.
Meisel, T., Walker, J. R., Morgan, J. W., 1996. The osmium isotopic composition of the earth's upper mantle. Nature, 383: 517-520.
Meisel, T., Walker, R. J., Irving, A, J., et al., 2001. Osmium isotopic compositions of mantle xenoliths: A global perspective. Geochim. Cosmochim. Acta, 65 (8): 1311 -1323. doi: 10.1016/S0016-7037(00)00566-4
Morgan, J. W., 1985. Osmium isotope constraints on earth's late accretionary history. Nature, 317: 703-705. doi: 10.1038/317703a0
Palme, H., Jones, A., 2004. Solar system abundances of the elements. In: Holland, H. D., Turekian, K. K., eds., Treatise of geochemistry, 1. Elsevier-Pergamon, Oxford, 41-62.
Palme, H., O'Neill, H. St. C., 2004. Cosmochemical estimates of mantle composition. In: Holland, H. D., Turekian, K. K., eds., Treatise of geochemistry, 2. Elsevier-Pergamon, Oxford, 1-38.
Pearson, D. G., 1999. Age of continental root. Lithos, 48: 171 -194.
Reisberg, L. C., Lorand, J. P., 1995. Longevity of subcontinental mantle lithosphere from osmium isotope systematics in orogenic peridotite massifs. Nature, 376: 159-162.
Righter, K., Hauri, E. H., 1998. Compatibility of rhenium in garnet during mantle melting and magama genesis. Science, 280: 1737-1741. doi: 10.1126/science.280.5370.1737
Roy-Barman, M., Wasserburg, G. J., Papanastassion, D. A., et al., 1998. Osmium isotope compositions and Re-Os concentrations in sulfide globules from basaltic glasses. Earth Planet. Sci. Lett., 154: 331-347.
Rudnick, R L., Gao, S., 2004. Composition of the continental crust. In: Holland, H. D., Turekian, K. K., eds., Treatise of geochemistry, 3. Elsevier-Pergamon, Oxford, 1-64.
Shirey, S. B., Walker, R. J., 1998. The Re-Os isotope system in cosmochemistry and high-temperature geochemistry. Ann. Rev. Earth Planet. Sci. Lett., 26: 423-500.
Shen, J. J., Papanastassiou, D. A., Wasserburg, G. J., 1996. Precise Re-Os determinations and systematics of iron meteorites. Geochim. Cosmochim. Acta, 60(15): 2887 -2900.
Smoliar, M. I., Walker, R J., Morgan, J. W., 1996. Re-Os ages of group Ⅱ A, Ⅲ A, Ⅳ A and ⅣB iron meteorites. Science, 271: 1099-1102.
Tsuru, A., Walker, R J., Kontinen, A., Pe., 2000. Re-Os isotopic systematics of 1.95 Ga Jormua ophiolite complex, northeastern Finland. Chem. Geol., 164: 123-141.
Walker, R J., Carlson, R W., Shirey, S. B., et al., 1989. Os, Sr, Nd and Pb isotopic systematics of southern African peridotite xenoliths: Implications for the chemical evolution of subcontinental mantle. Geochim. Cosmochim. Acta, 53: 1583-1595.
Walker, R J., Hanski, E., Vuollo, J., et al., 1996. The Os isotopic composition of Proterozoic upper mantle: Evidence for chondritic upper mantle from the Outokumpu ophiolite, Finland Earth Planet. Sci. Lett., 141, 161-173.
Walker, R. J., Horan, M. F., Morgan, J. W., et al., 2002. Comparative 187Re-188Os systematics of chondrites: Implications regarding early solar system processes. Geochim. Cosmochim. Acta, 66(23): 4187-4201.
Walker, R. J., Morgan, J. W., 1989. Rhenium-osmium isotope systematics of carbonaceous chondrites. Science, 243: 519-522.
Walker, R J., Shirey, S. B., Stecher, O., 1998. Comparative Re-Os, Sm-Nd, and Rb-Sr isotope and trace element systematics for Archean komatiite flow from Munro Township, Abitibi Nelt, Ontario. Earth Planet. Sci. Lett., 31: 97-105.
Xia, Q. X., Zhi, X. C., Li, J. H., et al., 2004. Chondritic osmium isotopic composition of Late Archean convective upper mantle: Evidence from Zunhua podiform chromi-tites, Hebei, North China. Chinese Science Bulletin, 49 (23): 2515-2520.