欢迎访问现代地质!

现代地质 ›› 2020, Vol. 34 ›› Issue (04): 769-783.DOI: 10.19657/j.geoscience.1000-8527.2020.04.13

• 石油地质学 • 上一篇    下一篇

鄂尔多斯盆地下三叠统刘家沟组与和尚沟组红层成色机制

谭聪1(), 于炳松2, 袁选俊1(), 刘策1, 王铜山1, 朱玺3   

  1. 1.中国石油勘探开发研究院,北京 100083
    2.中国地质大学(北京) 地球科学与资源学院,北京 100083
    3.辽宁省化工地质勘查院,辽宁 锦州 121000
  • 收稿日期:2019-08-15 修回日期:2019-12-13 出版日期:2020-08-31 发布日期:2020-09-03
  • 通讯作者: 袁选俊
  • 作者简介:袁选俊,男,教授级高工,博士生导师,1963年出生,沉积学专业,主要从事含油气盆地沉积学、储层地质学研究。Email: yxj@petrochina.com.cn
    谭 聪,女,博士,1989年出生,矿产普查与勘探专业,主要从事沉积学、油气地球化学研究。Email: 340330888@qq.com
  • 基金资助:
    国家科技重大专项“深层/超深层油气成藏规律与先进探测技术”(2018A-0104)

Color Origin of the Lower Triassic Liujiagou and Heshanggou Formations Red Beds in the Ordos Basin

TAN Cong1(), YU Bingsong2, YUAN Xuanjun1(), LIU Ce1, WANG Tongshan1, ZHU Xi3   

  1. 1. Research Institute of Petroleum Exploration & Development, Beijing 100083, China
    2. School of Earth Science and Resources, China University of Geosciences, Beijing 100083, China
    3. Liaoning Chemical Geology Exploration Institute, Jinzhou,Liaoning 121000, China
  • Received:2019-08-15 Revised:2019-12-13 Online:2020-08-31 Published:2020-09-03
  • Contact: YUAN Xuanjun

摘要:

鄂尔多斯盆地下三叠统刘家沟组与和尚沟组为一套规模巨大的红色砂泥岩沉积,其形成原因,仍存在疑问。以下三叠统刘家沟组与和尚沟组为研究对象,借助钻井岩心和野外剖面的观察描述、偏光显微镜、扫描电子显微镜、X射线衍射矿物成分分析以及主、微量元素分析等手段,结合红层上下其他颜色地层的对比,对这套红层的沉积特征和形成古气候背景进行研究,探讨其成因和成色机制。通过研究发现鄂尔多斯盆地的下三叠统刘家沟组与和尚沟组的红层是干旱炎热气候和强氧化环境的沉积产物,为原生成因,其红色主要来自作为染色剂的赤铁矿。通过上下不同颜色沉积岩对比研究发现,沉积岩出现不同的颜色主要是由于矿物组成不同,是盆地构造演化和气候环境变迁的结果。

关键词: 鄂尔多斯盆地, 下三叠统, 红层, 成色机制

Abstract:

The Lower Triassic Liujiagou and Heshanggou formations (Fms.) of the Ordos Basin in China contain large-scale red sandstone-mudstone deposition. Due to their lack of fossils and marker beds, study of these strata is difficult and little research attention has been paid to them. In this study, the red beds of the Liujiagou and Heshanggou formations were studied by means of drill-core and outcrop observation, optical microscopy, scanning electron microscope (SEM), X-ray diffractometer (XRD) and whole-rock major-and trace-element analyses. In addition, comparison with other strata of different colors from around the red beds was performed. The XRD and SEM analyses show that the dominant clay minerals in the red beds are smectite±illite. Trace amounts of fine disseminated hematite on the smectite flakes of pore infill have given the red color to the rocks. Sedimentary facies and elemental geochemistry reveal that the red beds are the products of a hot arid climate and a strongly oxidizing environment. These red beds are of sedimentary origin. By comparing the red beds with the rocks of different colors, it is shown that the different colors of sedimentary rocks are due mainly to their mineral contents, which reflect the basinal tectonic evolution and changes in the climate and sedimentary environment.

Key words: Ordos Basin, Lower Triassic, red beds, color origin

中图分类号: