Petrography and geochemistry of Palaeozoic quartz-rich sandstones from Saudi Arabia: implications for provenance and chemostratigraphy
Petrography and geochemistry of Palaeozoic quartz-rich sandstones from Saudi Arabia: implications for provenance and chemostratigraphy
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DOI：
10.1007/s12517-016-2412-z
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发表时间：
2016-04
影响因子：
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通讯作者：
Alexander Bassis;M. Hinderer;G. Meinhold
中科院分区：
文献类型：
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作者：
Alexander Bassis;M. Hinderer;G. Meinhold
阿拉伯半岛有一个从寒武纪到二叠纪的厚层古生代地层。它不仅含有两个主要的古生代冰川沉积，而且还拥有主要的古生代烃源岩和储集岩。此外，古生界砂岩也是重要的含水层。如薄片所示，该序列以高度成熟的石英砂岩为主。它缺乏化石，岩性非常均匀。为了更好地了解物源、构造背景和地层关系，对砂岩进行了岩相学、常量和微量元素地球化学研究。从沙特阿拉伯南部（Wajid地区）以及中部和北方（塔布克地区）的两个研究地区采集了样本。我们在这里提出的数据集是第一个全面的研究，以涵盖整个古生代的继承在南部和北方的阿拉伯半岛的一部分。一些样本的碰撞信号是冈瓦纳大陆融合最后阶段的遗迹，由冰川沉积物带入盆地。主要和微量元素地球化学表明，新元古代基底附近的阿拉伯盾作为最有可能的来源的碎屑。构造判别图解表明，砂岩的沉积发生在克拉通背景下，这是根据阿拉伯板块演化的既定模型。在Wajid地区的晚古生代单元确实出现了可能来自地盾的新鲜物质的流入，但没有到达塔布克地区。地球化学方法在描述这两个研究区域的物源方面取得了一些成功，但无法可靠地评估沉积物的再循环。因此，古生代砂岩的（Meta）沉积物来源既不能被证明也不能被反驳。多元聚类和主成分分析表明，两个研究区的地球化学数据之间的显着差异。
The Arabian Peninsula hosts a thick Palaeozoic succession, ranging from the Cambrian through the Permian. It not only contains deposits of the two major Palaeozoic glaciations but also holds both the major Palaeozoic hydrocarbon source and reservoir rocks. In addition, Palaeozoic sandstones serve as important aquifers. The succession is dominated by highly mature quartz arenites, as seen in thin sections. It is starved of fossils and very uniform in lithology. In order to better understand provenance, tectonic setting and stratigraphic relationships, the petrography as well as major and trace element geochemistry of sandstones were studied. Samples were taken from two study areas in southern (Wajid area) as well as central and northern (Tabuk area) Saudi Arabia. The dataset we present here is the first comprehensive study to cover the entire Palaeozoic succession in both the southern and northern part of the Arabian Peninsula. The collisional signal from some samples is a relic from the last stages of the amalgamation of Gondwana, carried into the basin by glaciogenic sediments. Major and trace element geochemistry indicate the Neoproterozoic basement of the nearby Arabian Shield as the most likely source for the detritus. Tectonic discrimination diagrams suggest that deposition of sandstones took place in an intracratonic setting, which is in accordance with the established model for the evolution of the Arabian Plate. An influx of fresh material, probably sourced from the Shield, did occur in the late Palaeozoic units of the Wajid area but did not reach the Tabuk area. Geochemical methods have shown some success in characterising the provenance of both study areas but were unable to reliably assess sedimentary recycling. A (meta-)sedimentary source for the Palaeozoic sandstones could therefore neither be proven nor refuted. Multivariate cluster and principal component analysis of geochemical data revealed significant differences between the two study areas.