地球科学进展 ›› 1995, Vol. 10 ›› Issue (4): 373 -377. doi: 10.11867/j.issn.1001-8166.1995.04.0373

干旱气候变化与可持续发展 上一篇    下一篇

对南极类C1陨石成因和星云水化作用范围的几点看法
侯渭,欧阳自远   
  1. 中国科学院地球化学研究所  贵阳  550002
  • 收稿日期:1994-08-15 修回日期:1994-09-26 出版日期:1995-08-01
  • 通讯作者: 侯渭
  • 基金资助:

    国家自然科学基金项目“地球早期壳幔化学演化的实验研究”(编号:49373180)资助.

A DISCUSSION ON SOME ANTARCTIC QUASI-C1 CHONDRITES ORIGIN AND RANGE OF NEBULAR HYDROUS EFFECT

Hou Wei, Ouyang Ziyuan   

  1. Institute of Geochemisry, Chinese Academy of Sciences, Guiyang  550002
  • Received:1994-08-15 Revised:1994-09-26 Online:1995-08-01 Published:1995-08-01

南极陨石的研究发现,有几个碳质球粒陨石富含与Cl陨石类似的含水层状硅酸盐集合体及其角砾,其氧同位素比值也与Cl接近,因而称之为类Cl陨石。类Cl陨石与Cl陨石的区别是:类Cl陨石中的含水层状硅酸盐既以基质的形式产出,也出现在球粒中;类Cl陨石中含有球粒及有关组分,如球粒碎块、矿物集合体等。每个陨石中所含这些组分的数量不同,其矿物的成分也差别很大,从而说明它们形成的星云环境不同。因此笔者认为类Cl陨石可能是小行星区星云盘外层的星云凝聚物受到不同程度水化作用后吸积形成的陨石。

Because of containing many phyllosilicate aggregates and similar oxygen isotopic composition to C1 carbonaceous chondrite, the Antarctic carbonaceous chondrite, Y-82162, Y-86720, Belgica-7904,PCA-91082, Y-793495 and Y-8449 are called as quasi-C1 chondrite. In these carbonaceous chondrites the phyllosilicate aggregates exist as four forms: (1)matrix, (2)clast with same composition of matrix, (3)chondrule, (4)dark inclusion. This four forms are independence relatively in meteorite, so the hydrous effect must take place after nebular condensation and before meteorite parent body formation. Besides phyllosilicate aggregates, some higher temperature condensates or their remainder, for example, non-completely hydrous chondrite, anhydrous silicate mineral and their aggregate, appear in these meteorites. In different meteorite the composations of higher temperature condensate remainder are various, from enstatite, silica mineral, to moderate Fe-rich o-livine, Fe-rich olivine. According to above evidences and this fact that water has been observed on Mar, Earth and Mercury, we consider that range of nebular hydrous effect could be wide, including terrestrial planet region and asteroids region of solar nebular.

[1] Tomeoka K et al. Yamato-82162: A new kind of CI carbonaceous chondrite found in Antarctica. Proceedings of the NIPR on Antarctic Meteorites,1989,2:36-54.
[2] Tomeoka K et al. Yamato-86720: A CM carbonaceous chondrite having experienced extensive aqueous alteration and thermal metamorphism. Proceedings of the NIPR on Antarctic Meteorites,1989,2:55-74.
[3] Tomeoka K. Mineralogy and petrology of Belgica-7904: A new kind of carbonaceous chondrite from Antarctica. Proceedings of the NIPR on Antarctic Meteorites,1990,3:40-54.
[4] Yamamoto K and Makamura N. REE characteristics of Yamato-82162 and -86720 meteorites and their inference to classification. Proceedings of the NIPR on Antarctic Meteorites,1990,3:69-79.
[5] Paul R L. Lipschutz. Consortium study of labile trace elements in some Antarctic carbonaceous chondrites: Antarctic and non-Antarctic meteorite comparisons. Prceechings of the NIPR on Antarctic Meteorites,1990,3:80-95.
[6] Prinz M et al.Type I and II chondres in the B-7904 carbonaceous chondrire. Abstract of 52th Meeting of the Meteoritical Society,1989.317-318.
[7] Noguchi T. Comparison of petrology and mineralogy of thePCA-91082 and the Yamato-793495(CR) chondrites: on the phyllosilicate clasts. Papers presented to the nineteenth symposiumon Antarcric meteorites. National Institute of Polar Research,TOKYO,1994,16-17.
[8] Ichikawa O and Ikeda Y. Petrology of Yamato-8449 chondrite (CR). Papers presented to the nineteenth symposium on Antarctic mereorites. National Institute Polar Researeh,TOKYO,1994,18-19.
[9] Weisberg M. The CR Chondrite Clan. Papers presented to the nineteenth symposiumon Antarctic meteorites. National Institute of Polar Researeh,TOKYO,1994,131-133.
[10] 美国天文家发现水星上存在冰湖.中国科学报(国际科技版),1994年7月15日.

[1] 王道德. 南极陨石的收集和研究进展[J]. 地球科学进展, 1990, 5(1): 21-27.
阅读次数
全文


摘要