Abstract The Upper Jurassic Jubaila Formation in central Saudi Arabia exhibits laterally coeval environments from the southwest to the northeast. These coeval environments involve inner, mid-, and outer ramps. The inner ramp occurs at the Al Haddar section in the extreme southwest and consists of mixed clastic-carbonate facies and are represented by intercalations of ferruginous calcareous quartz arenite, ferruginous sublitharenite, and burrowed dolomicrite. In the mid-ramp setting, there were changes from lateral facies in the Riyadh and the Wadi Huraymila areas to carbonates characterized by sandy lime-mudstones, dolosparie, peloidal olitic packstones, and coralline bioclastic wackestones to packstones. These are intercalated with sandy lime-mudstones that might be deposited in highly agitated environments. The outer-ramp setting occurred in the farther northeast Al Uyaynah area. It is characterized by reduced thickness and is composed of lime-mudstones, dolomitic marls, and pelletal bioclastic wackestones with thin beds of dolomitic marls. The lateral and vertical microfacies distribution in the Jubaila Formation are arranged vertically into four 3rd-order cycles that are correlate laterally overall the studied area, which are overprinted by oscillations in eustatic sea-level during the deposition of Jubaila Formation.

中文翻译：

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沙特阿拉伯中部上侏罗统（Kimmeridgian）朱拜拉组的岩相结构和沉积历史

摘要 沙特阿拉伯中部上侏罗统朱拜拉组呈现出自西南向东北的横向同期环境。这些同时代的环境涉及内部、中间和外部坡道。内斜坡出现在最西南端的 Al Haddar 剖面，由混合碎屑-碳酸盐相组成，以铁质钙质石英砂岩、铁质亚岩屑岩和洞穴白云岩的夹层为代表。在中间匝道环境中，从利雅得和 Wadi Huraymila 地区的侧相转变为以砂质灰泥岩、白云岩、球状碲质泥岩和珊瑚状生物碎屑泥岩为特征的碳酸盐岩。它们夹杂着砂质石灰泥岩，这些砂质石灰泥岩可能沉积在高度搅动的环境中。外匝道设置发生在更远的东北部 Al Uyaynah 地区。它的特点是厚度减小，由石灰泥岩、白云质泥灰岩和具有白云质泥灰岩薄层的球状生物碎屑碎屑岩组成。朱拜拉组的横向和垂直微相分布垂直排列成四个三阶旋回，这些旋回与整个研究区域横向相关，这些旋回被朱拜拉组沉积期间静海平面的振荡叠加。