新疆石油地质 ›› 2019, Vol. 40 ›› Issue (zk(English) ): 290-297.

• • 上一篇    下一篇

Meandering River Deposit and Sand Body Architecture in Qigu Formation of Jiangong Coal Mine Section in the Southern Margin of Junggar Basin

GUAN Xutong1, WU Jian2, WEI Lingyun2, ZHAO Jinyong2, FENG Geng1, LI Yan1   

  1. 1.MOE Key Laboratory of Orogenic Belts and Crustal Evolution, Peking University, Beijing 100871, China;
    2.Institute of Geophysics, Research Institute of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Urumqi, Xinjiang 830011, China
  • 收稿日期:2019-02-11 修回日期:2019-04-08 出版日期:2020-01-01 发布日期:2021-05-18

Meandering River Deposit and Sand Body Architecture in Qigu Formation of Jiangong Coal Mine Section in the Southern Margin of Junggar Basin

GUAN Xutong1, WU Jian2, WEI Lingyun2, ZHAO Jinyong2, FENG Geng1, LI Yan1   

  1. 1.MOE Key Laboratory of Orogenic Belts and Crustal Evolution, Peking University, Beijing 100871, China;
    2.Institute of Geophysics, Research Institute of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Urumqi, Xinjiang 830011, China
  • Received:2019-02-11 Revised:2019-04-08 Online:2020-01-01 Published:2021-05-18
  • About author:GUAN Xutong, E-mail: guanxt@pku.edu.cn

摘要: Guided by the theories of sedimentary and architectural-element analysis, the paper analyzed the architectural elements of the meandering river sand body in Upper Jurassic Qigu formation in the southern margin of Junggar basin, counted the scale and shapes of the architectural elements and sand bodies and classified the superimposition types. In this field outcrop, 7 lithofacies are found, boundaries with 6 levels are classified and 4 key architectural elements are identified. When the A/S is bigger than 1, the isolated channel sand bodies are developed. As the A/S decreases and approaches to 1, the bridging channel sand bodies and superimposed channel sand bodies are developed. When the A/S is smaller than 1, the truncated channel sand bodies are developed. During the deposition of Qigu formation, the climate was arid and hot. During the deposition of Toutunhe formation, the broad lake level dropped, a sandy meandering river formed with the depth of about 33.3 m, width of 139.2 m, bankfull width of 805.2 m and single meander belt width of 6405.2 m. In the early stage of the deposition of Qigu formation, the A/S was smaller than 1, corresponding to the development of isolated channel and flood lake sand bodies, in the middle stage, the bridging channel sand bodies, superimposed channel sand bodies and the truncated channel sand bodies were developed. In the late stage, the A/S increased again corresponding to the development of the isolated channel sand bodies.

关键词: Junggar basin, southern margin, Jiangong coal mine section, Upper Jurassic, Qigu formation, fluvial deposit, architectural element, superimposition type

Abstract: Guided by the theories of sedimentary and architectural-element analysis, the paper analyzed the architectural elements of the meandering river sand body in Upper Jurassic Qigu formation in the southern margin of Junggar basin, counted the scale and shapes of the architectural elements and sand bodies and classified the superimposition types. In this field outcrop, 7 lithofacies are found, boundaries with 6 levels are classified and 4 key architectural elements are identified. When the A/S is bigger than 1, the isolated channel sand bodies are developed. As the A/S decreases and approaches to 1, the bridging channel sand bodies and superimposed channel sand bodies are developed. When the A/S is smaller than 1, the truncated channel sand bodies are developed. During the deposition of Qigu formation, the climate was arid and hot. During the deposition of Toutunhe formation, the broad lake level dropped, a sandy meandering river formed with the depth of about 33.3 m, width of 139.2 m, bankfull width of 805.2 m and single meander belt width of 6405.2 m. In the early stage of the deposition of Qigu formation, the A/S was smaller than 1, corresponding to the development of isolated channel and flood lake sand bodies, in the middle stage, the bridging channel sand bodies, superimposed channel sand bodies and the truncated channel sand bodies were developed. In the late stage, the A/S increased again corresponding to the development of the isolated channel sand bodies.

Key words: Junggar basin, southern margin, Jiangong coal mine section, Upper Jurassic, Qigu formation, fluvial deposit, architectural element, superimposition type