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在碱质FeO-MgO,K_2O—Na_2O-CaO和标准矿物分子的Q-Ab-Or图上,对太古代岩石中的主要元素和痕量元素丰度进行了比较。也对K与Rb、Sr、Ba的比值和U以及U和Th的比值进行了对比。苏联地盾的分异程度要比加拿大地盾强些,而火成杂岩一般要比与其相伴生的基底岩层分异得好些。对同一地质单元而言,Fe/Mg成分的平均比值变化大,绿岩的平均值也有较大的变化范围。麻粒岩相的镁含量要高于平均值,而阿米特索克(Amitsoq)片麻岩和卡普瓦尔年轻花岗岩侵入体则明显地富铁。据主要元素和痕量元素的含量,老片麻杂岩包括云英闪长岩在成分上是介于北大西洋陆核的麻粒岩和闪岩相之间的平均值,因此也就提出一个问题,就是它相当于北大西洋麻粒岩相的高层位产物,还是它的分异岩相。K/U比值大部分都大于10000,但是斯科灵(Scour-ian)和阿米特索克片麻岩例外。Th/U比值变化范围大,但是一般说来要高于推测的地壳平均值。绿岩带和一些片麻杂岩的痕量元素的某些特征可与高热梯度的存在和在40公里深处含有一角闪石层的富钾水的地幔最上部进行尝试性的对比。
The abundances of major elements and trace elements in Archean rocks were compared on the Q-Ab-Or maps of alkali FeO-MgO, K2O-Na2O-CaO and standard mineral molecules. The ratios of K to Rb, Sr, Ba and the ratios of U and U to Th were also compared. The Soviet shield is much more differentiated than the Canadian shield, and igneous complexes are generally better than the associated basement strata. For the same geological unit, the average ratio of Fe / Mg composition varies greatly, and the average value of greenstone also has a larger range of variation. Magnesium content of the granulite facies is higher than average, whereas the Amitsoq gneiss and the Kapocha granite intrusions are significantly iron-rich. According to the contents of major elements and trace elements, the ophiolites, including the dolomitic diorites, are compositionally averaged between the granulites and amphibolite facies in the North Atlantic nucleus, and hence also propose a The problem is that it is equivalent to the high-level product of the granulite facies in the North Atlantic Ocean, or its divergent facies. K / U ratios are mostly greater than 10,000, with the exception of the Scour-ian and the Amitosuch gneiss. The Th / U ratio varies widely, but is generally above the presumed crustal averages. Some characteristics of the trace elements of the greenstone belt and some gneiss complexes can be tentatively compared with the presence of a high thermal gradient and the uppermost mantle of potassium-rich water containing an amphibole layer at a depth of 40 km.