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野外考察发现,雅布赖盆地红柳沟发育一套较完整的中侏罗统扇三角洲沉积地层。其中沉积亚相有扇三角洲平原、扇三角洲前缘及前扇三角洲亚相;沉积微相包括辫状河道、天然堤、决口、沼泽、水下分流河道、水下分流河道间、河口坝、席状砂等沉积微相。从沉积构造特征分析可以看出,河道沉积发育于水动力条件较强的沉积环境,扇三角洲前缘河口坝沉积发育于强与弱水动力条件交替出现的沉积环境,而前扇三角洲则在比较稳定的水动力条件下沉积。对野外6个泥岩样品的微量元素化验结果用蜘蛛图解分析处理,得到样品所含微量元素V、Sr、Rb、B相对富集,而Zr、Cr、Ni相对亏损。通过对该地区样品w(Fe2+)/w(Fe3+)及气候指数计算表明,当时为弱氧化、半干旱的沉积环境。
Field investigation found that a complete set of middle Jurassic fan delta sedimentary strata was developed in Hongliugou of the Yabulai Basin. Sedimentary microfacies include braided channels, natural dike, bursts, swamps, underwater distributary channels, underwater distributary channels, estuarine dams, seats Sand and other sedimentary microfacies. From the analysis of sedimentary structural characteristics, it can be seen that the river sediments are developed in a sedimentary environment with strong hydrodynamic conditions. The sedimentation of the fan delta front mouth barrage dam develops in the sedimentary environment where the strong and weak hydrodynamic conditions alternate with the former fan delta Stable under hydrodynamic conditions. Trace elements analysis results of six mudstone samples in the field were analyzed by spiders. The trace elements V, Sr, Rb and B in the samples were relatively enriched while the relative loss of Zr, Cr and Ni was obtained. Calculation of w (Fe2 +) / w (Fe3 +) and climate index in this area shows that it was a weakly oxidized and semi-arid sedimentary environment at that time.