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华北地区石盒子群的沉积环境长期以来一致存在较大的争议,大多数研究者认为该时期完全为陆相沉积,也有一些学者在该地层中发现了海相沉积物。本文着重对鲁西、河南等地区石盒子群的奎山砂岩进行岩石学、沉积学、地球化学等指标研究,在该砂岩中发现了冲洗交错层理,并在该砂岩中上部发现了海绿石的存在。通过详细分析奎山砂岩中海绿石的显微特征、元素地球化学特征,并进行比较研究发现,华北地区奎山砂岩中海绿石的化学成分、含量与国内外古代的海相、过渡相海绿石基本一致,推断其为滨浅海富氧环境的产物。华北地区奎山砂岩中发育的沉积构造和所含海绿石的元素地球化学特征,揭示了该时期曾发生过海侵,反映了石盒子群沉积期沉积环境的复杂性。华北地区石盒子群奎山砂岩中上部海相沉积环境的确定,可能改变华北盆地二叠纪以来单纯为陆相沉积的认识,这为精细研究华北地区中晚二叠世的盆地格局、充填演化及恢复古地理景观,提供了新的思路和重要依据。
The sedimentary environment of stone box subgroups in North China has long been quite controversial. Most researchers think that this period was completely continental deposition. Some scholars also found marine sediments in the strata. This paper focuses on the petrology, sedimentology and geochemistry of Kuishan sandstone in Shi box subgroup in Luxi, Henan and other regions. In this sandstone, the cross-bedding stratification was discovered and the sea green was found in the upper part of the sandstone Stone’s existence. By analyzing the microscopic characteristics and elemental geochemical characteristics of glauconite in the Kuishan sandstone and comparing them, it is found that the chemical composition and content of glauconite in the Kuishan sandstone in North China are similar to those of the ancient marine facies at home and abroad, Stone basically the same, infer that the coastal shallow sea oxygen-rich environment product. The sedimentary structures developed in the Kuishan sandstone of North China and the elemental geochemical characteristics of the contained glauconite reveal the transgression that occurred during this period and reflect the complexity of sedimentary environment during the sedimentary period. Determining the upper marine sedimentary environment of the Quanshanzi sandstone in the Shihezi Group in North China may change the understanding of continental sediments since the Permian in the North China Basin. This is a detailed study of the basin pattern and filling evolution of the Middle and Late Permian in North China And restore the ancient geographical landscape, providing a new way of thinking and an important basis.