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阿拉伯地盾前寒武纪火山岩和深成岩的铷—锶法研究指出,在9亿和6.8亿年前之间,阿拉伯半岛有陆壳的早期发育。地质研究表明,克拉通内的岛—弧环境沿南北向或北西向轴,以具安山岩(闪长岩)岩浆活动、火山碎屑沉积、快速沉淀作用和同期变形为特征。沙特阿拉伯西部和西南部所见年龄为9—8亿度的最早深成岩是闪长岩到奥长花岗岩岩基。年龄为7.5—6.8亿年的较新岩石组分则从石英闪长岩到花岗闪长岩变化,这些组份在阿拉伯地盾的中南部和东部变得更多了。上述两组岩石的~(87)Sr/~(86)Sr初始值为0.7023到0.7030,平均为0.7027。沉积地层中硅铝质岩屑的缺失和岛—弧环境事件意味着板块和大洋岩圈之间,阿拉伯陆壳早期发育产生在会聚板块边缘上,随之发生与俯冲作用有关的岩浆作用和构造作用,称之为汉志构造旋回。在阿拉伯和非洲东部,以泛非事件为代表的碰撞事件期间,阿拉伯为非洲元古宙板块所缝合,延伸到从6.5亿年前到至少5.4亿年,甚至可能到5.2亿年前。当9亿至5亿年期间,尽管俯冲作用和大陆碰撞作用在此板块会聚的简单板块构造模式为代表,根据泛非事件的年龄差异以及汉志造山运动岩浆作用和构造作用的差异,支持了至少可划分为两个事件的看法。主要深成侵入作用时期的分布表明,汉志旋回期间,岩浆和构造活动轴是向东或向北东移动的。然而,泛非事件的花岗闪长岩到花岗岩深成作用说明它们随年龄并没有限定的地理变化,而且深成岩分布在整个阿拉伯地盾中。
Arabian Shield Precambrian volcanic and plutonic rubidium-strontium studies indicate that between 900 and 680 million years ago, the Arabian Peninsula had early development of the continental crust. Geological studies have shown that the island-arc environment in the craton is characterized by anamorphic (diorite) magmatic activity, volcaniclastic sedimentation, rapid sedimentation and synodic deformation along the north-south or north-west axis. The earliest plutons aged 9-8 billion degrees seen in western and south-western Saudi Arabia are diorite to diabase granite. The newer rock components, aged 7.5-6.8 billion years, vary from quartz diorite to granodiorite, and these components have become more abundant in the south central and eastern parts of the Arabian Shield. The initial values of ~ (87) Sr / ~ (86) Sr in the above two groups of rocks are 0.7023 to 0.7030 with an average of 0.7027. The absence of Si-Al cuttings and the island-arc environmental events in the sedimentary formations mean that the early development of the Arabian continental crust occurred between the plate and the oceanic lithosphere on the margins of the convergence plateau, with consequent magmatism and tectonics associated with subduction Role, called Han Zhi structure cycle. In the Arabs and eastern Africa, during the collision incident represented by the Pan-African incident, Arabia was sutured into the Proterozoic African plate extending from 650 million years ago to at least 540 million years and possibly to 520 million years ago. Although the simple plate tectonic model of subduction and continental collision in this plate convergence between 900 million and 500 million years is representative, it is supported by the age difference of Pan-African events and the difference between magmatism and tectonic function of Han orogenic movement At least can be divided into two events view. The distribution of the major deep-buried intrusions shows that during the Hanshi cycle, the magmatic and tectonic axes moved eastward or northward. However, the granodiorite to granite deep pan-African event indicates that they are geographically indeterminate with age and that plutons are distributed throughout the Arabian shield.