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阿尔丹地盾的太古宙杂岩可划分为两大构造单位:1.早太古宙基底,2.晚太古宙-早元古代上地壳海槽(绿岩或片岩带)。最老的基底岩石,已确定年龄比3500Ma(远太古宙)更老。基性片岩(主要为正辉石和二辉石麻粒岩)已知是出露的最下部基底变质岩层。这些岩层被石英岩、高铝片岩和碳酸盐岩(延格拉岩系)所复盖。复盖在该岩系之上的是基性片岩和含有碳酸盐岩夹层的黑云母-闪石-石榴石片麻岩(提姆普顿-扎尔土拉岩系)。由于交代作用而转变成
Ardan Shield Archean complex can be divided into two major structural units: 1. Early Archean basement, 2. Late Archean - Early Proterozoic upper crustal trough (greenstone or schist). The oldest basement rock has been determined to be older than 3500Ma (Far Archean). Basic schists (mainly, orthopyroxene and daryolitic granulites) are known to be the lowest exposed basement metamorphic rocks. These rock formations are covered by quartzite, high-aluminum schist, and carbonate rocks (Yanjala). Overlying this series are basic schists and biotite-amphibole-garnet gneiss (Timpton-Zar-Tula series) with carbonate intercalations. Transformed into due to accountability