鄂尔多斯盆地下侏罗统富县组沉积体系及古地理
The depositional systems and palaeogeography of the Lower Jurassic Fuxian Formation in the Ordos Basin
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摘要: 富县组是鄂尔多斯盆地侏罗系最早沉积的地层,其发育在由印支运动所造成的凹凸不平剥蚀面上,沉积以填平补齐为特点,与下伏三叠系延长组呈不整合接触关系。富县组沉积厚度变化大,岩性差异明显,岩相复杂。沉积相在空间上变化较大,为河流相和冲积扇相沉积。Abstract: The Ordos Basin is one of the largest Mesozoic coal-bearing basins and continental petroleum basins in China. The Fuxian Formation represents the earliest Jurassic sedimentary strata in the basin developed upon the denudational surface generated during the Indosinian orogeny, and is overlain unconformably upon the underlying Triassic Yanchang Formation. The sediment thickness and lithology are highly variable. The deposition here is maniested in filling, and the depositional systems consist of the alluvial fan and fluvial sediments, where the channel facies has more potential as oil and gas reservoirs if the cover of the channel sediments in the formation are favourable.