【摘要】：準(zhǔn)噶爾盆地瑪湖凹陷下三疊統(tǒng)百口泉組為一套扇三角洲沉積體系,以粗碎屑沉積為主,夾少量的泥巖。為了恢復(fù)百口泉組沉積時(shí)期水體的古鹽度,并與上二疊統(tǒng)烏爾禾組、中三疊統(tǒng)克拉瑪依組的古鹽度對(duì)比,對(duì)上述3個(gè)組巖心中的泥巖樣品開(kāi)展了全巖黏土礦物分析和微量元素測(cè)試,采用硼元素法、鍶鋇比、硼鎵比等方法恢復(fù)百口泉組沉積時(shí)期水體的古鹽度。結(jié)果表明,泥巖樣品中黏土礦物以伊蒙混層為主,適合用科奇公式恢復(fù)古鹽度�，敽枷轂鯛柡探M、百口泉組一段、百口泉組二段、百口泉組三段和克拉瑪依組的平均古鹽度分別為7.0‰,5.0‰,7.2‰,8.9‰和8.4‰,反映當(dāng)時(shí)水體為淡水—微咸水環(huán)境;黃羊泉扇與夏子街扇百口泉組表現(xiàn)出不同的古鹽度變化趨勢(shì),黃羊泉扇的古鹽度值較低,而夏子街扇的古鹽度值相對(duì)較高,可能與所選井位的古沉積環(huán)境有關(guān)。此外,鍶鋇比和硼鎵比也指示瑪湖凹陷晚二疊世—中三疊世水體為淡水—微咸水環(huán)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，

本文編號(hào)：2464439