Geochemical evidence for the origin of australites
Geochemical evidence for the origin of australites
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澳大利亚石起源的地球化学证据
DOI：
10.1016/0016-7037(64)90150-4
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发表时间：
1964
影响因子：
5
通讯作者：
M. Sachs
中科院分区：
文献类型：
--
作者：
S. Taylor;M. Sachs
对澳大利亚岩进行了十九次新的分析。43种澳大利亚陨石的平均成分（包括Taylor，1962 a的24个分析）如下：P，200 ppm; Si，34.25%（73.31%SiO2）; Al，6.18%（11.68% Al2O3）; Ga，8.3 ppm; Cr，75 ppm; Mg，1.22%（2.02% MgO）; Li，42 ppm; Ti，4130 ppm; Ni，30 ppm; Co，15 ppm; Cu，7.3 ppm; Fe，3.54%（4.03% FeO; 0.60% Fe2O3）; V，76 ppm; Zr，410 ppm; Mn，760 ppm; Sc，12 ppm; Na，0.93%（1.25% Na2O）; Ca，2.50%（3.50% CaO）; Sr，200 ppm; K，1.88%（2.26% K2O）; Ba，620 ppm; Kb，84 ppm; Cs，2.7 ppm。讨论了成分的可能区域变化，并与达尔文玻璃和冲击玻璃进行了比较。与此相反，没有观察到明显的陨石贡献的澳大利亚组成。元素的丰度是特别重要的玻璃陨石成因进行了讨论。它们是：Cs; Mg、Li和K; Ti和Zr; U和Th; Ni、Co和Cr; Ca、Sr和Ba; Ga、Cu和Pb;以及稀土。这些元素的丰度，无论是相对的还是绝对的，都类似于那些混合良好的地表物质。他们是不符合火成岩丰度，也没有改变显着的挥发性元素的选择性蒸馏。玻璃陨石的起源地进行了讨论，特别是参考陆地或月球的起源。主元素和微量元素的丰度，以及铅和锶的同位素比率，支持母源来自地球或完全相似的行星。我们目前的想法的组成和历史的月球表面给出了一节是包括在可能的组成月球酸的区别。我们现有的知识排除了月球表面是澳大利亚岩源区的可能性。
Nineteen new analyses of australites are given. The average composition of 43 australites (including 24 analyses fromTaylor, 1962a) is as follows: P, 200 ppm; Si, 34.25% (73.31 % SiO2); Al, 6.18% (11.68% Al2O3); Ga, 8.3 ppm; Cr, 75 ppm; Mg, 1.22% (2.02% MgO); Li, 42 ppm; Ti, 4130 ppm; Ni, 30 ppm; Co, 15 ppm; Cu, 7.3 ppm; Fe, 3.54% (4.03% FeO; 0.60% Fe2O3); V, 76 ppm; Zr, 410 ppm; Mn, 760 ppm; Sc, 12 ppm; Na, 0.93% (1.25% Na2O); Ca, 2.50% (3.50% CaO); Sr, 200ppm; K, 1.88% (2.26% K2O); Ba, 620 ppm; Kb, 84 ppm; Cs, 2.7 ppm. A discussion is given of possible regional variation in composition and comparison is made with Darwin Glass and impact glasses. In contrast to these, no significant meteoritic contribution to australite composition is observed.Elements whose abundance is particularly significant for tektite origin are discussed. These are: Cs; Mg, Li and K; Ti and Zr; U and Th; Ni, Co and Cr; Ca, Sr and Ba; Ga, Cu and Pb; and the rare earths. The abundances of these elements, both relative and absolute, are similar to those in well-mixed terrestrial surface material. They are not consistent with igneous rock abundances, nor have they been altered significantly by selective distillation of volatile elements.The place of origin of tektites is discussed with special reference to a terrestrial or lunar origin. The major and trace-element abundances, with the lead and strontium isotope ratios, support an origin for the parent material from the earth, or an entirely similar planet. Our current ideas about the composition and history of the lunar surface are given and a section is included on the probable composition of lunar acid differentiates. Our present knowledge precludes the lunar surface from being a source area for australites.