准噶尔盆地玛湖凹陷下三叠统百口泉组古盐度恢复
发布时间：2019-04-24 12:13
【摘要】：准噶尔盆地玛湖凹陷下三叠统百口泉组为一套扇三角洲沉积体系,以粗碎屑沉积为主,夹少量的泥岩。为了恢复百口泉组沉积时期水体的古盐度,并与上二叠统乌尔禾组、中三叠统克拉玛依组的古盐度对比,对上述3个组岩心中的泥岩样品开展了全岩黏土矿物分析和微量元素测试,采用硼元素法、锶钡比、硼镓比等方法恢复百口泉组沉积时期水体的古盐度。结果表明,泥岩样品中黏土矿物以伊蒙混层为主,适合用科奇公式恢复古盐度。玛湖凹陷乌尔禾组、百口泉组一段、百口泉组二段、百口泉组三段和克拉玛依组的平均古盐度分别为7.0‰,5.0‰,7.2‰,8.9‰和8.4‰,反映当时水体为淡水—微咸水环境;黄羊泉扇与夏子街扇百口泉组表现出不同的古盐度变化趋势,黄羊泉扇的古盐度值较低,而夏子街扇的古盐度值相对较高,可能与所选井位的古沉积环境有关。此外,锶钡比和硼镓比也指示玛湖凹陷晚二叠世—中三叠世水体为淡水—微咸水环境。
[Abstract]:The Baikouquan formation of the Lower Triassic in Mahu Sag of Junggar Basin is a fan delta sedimentary system with coarse clastic deposits and a small amount of mudstone. In order to recover the paleosalinity of the Baikouquan formation during the sedimentary period, and to compare the paleosalinity of the Upper Permian Urhe formation and the Middle Triassic Karamay formation, The whole rock clay mineral analysis and trace element test were carried out for the mudstone samples in the core of the above three formations. The paleosalinity of the water body during the depositional period of the Baikouquan formation was restored by the methods of boron element method, strontium-barium ratio and boron-gallium ratio. The results show that the clay minerals in mudstone samples are mainly Aemon mixed layer, which is suitable for the restoration of paleo-salinity by Koch formula. The average paleosalinities of the Wuerhe formation, the Baikouquan formation, the second member of the Baikouquan formation, the third member of the Baikouquan formation and the Karamay formation are 7.0 鈥，
本文编号：2464439
[Abstract]:The Baikouquan formation of the Lower Triassic in Mahu Sag of Junggar Basin is a fan delta sedimentary system with coarse clastic deposits and a small amount of mudstone. In order to recover the paleosalinity of the Baikouquan formation during the sedimentary period, and to compare the paleosalinity of the Upper Permian Urhe formation and the Middle Triassic Karamay formation, The whole rock clay mineral analysis and trace element test were carried out for the mudstone samples in the core of the above three formations. The paleosalinity of the water body during the depositional period of the Baikouquan formation was restored by the methods of boron element method, strontium-barium ratio and boron-gallium ratio. The results show that the clay minerals in mudstone samples are mainly Aemon mixed layer, which is suitable for the restoration of paleo-salinity by Koch formula. The average paleosalinities of the Wuerhe formation, the Baikouquan formation, the second member of the Baikouquan formation, the third member of the Baikouquan formation and the Karamay formation are 7.0 鈥，
本文编号：2464439
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