Structure and metamorphism of the Archean Murchison Belt, Kaapvaal Craton, South Africa
Structure and metamorphism of the Archean Murchison Belt, Kaapvaal Craton, South Africa
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南非卡普瓦尔克拉通太古代默奇森带的结构和变质作用
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发表时间：
1988
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通讯作者：
J. Vearncombe
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作者：
J. Vearncombe
对普遍适用于绿岩带，特别是默奇森带的五种流行偏见的批判性审查表明：（1）默奇森片岩带一词比默奇森绿岩带更受欢迎，默奇森绿岩带与巴伯顿绿岩带有很大区别;（2）默奇森带的构造作用使得不可能建立简单的地层;（3）默奇森带缺乏向斜龙骨，（4）不均匀的斜滑-倾滑剪切是Murchison带的主要特征，但走滑变形发生在带东北缘沿着的Letaba剪切带中;（5）接触变质作用是一种有限的现象，与Murchison带的最高级岩石无关。该带由若干区域组成，每个区域都有其独特的岩性、构造样式和变质历史，并以具有不同地壳水平并置岩石的构造断裂为界。
Critical examination of five popular prejudices applied to greenstone belts in general, and the Murchison belt in particular show that (1) the term Murchison schist belt is preferred to that of Murchison greenstone belt, which differs significantly from the Barberton greenstone belt, (2) the Murchison belt is tectonized such that no simple stratigraphy may be erected, (3) the Murchison belt lacks a synclinal keel, (4) heterogeneous oblique- to dip-slip shear characterizes much of the Murchison belt, but strike-slip deformation occurred in the Letaba shear zone along the northeastern margin of the belt, and (5) contact metamorphism was a limited phenomenon that was not responsible for the highest grade rocks of the Murchison belt. The belt comprises a number of domains, each with its own characteristic lithologies, structural style, and metamorphic history, bounded by tectonic breaks which have juxtaposed rocks from different crustal levels.