【摘要】 基于露头、岩心、钻(测)井等资料,对准格尔盆地西北缘上侏罗统齐古组沉积相及其沉积演化模式进行综合分析,研究表明:研究区齐古组中可分为q1、q2、q3三个砂层组,发育冲积扇、辫状河和三角洲3种沉积相类型,包括7种亚相和10种微相。q3砂层组时期,西部受克拉玛依断裂的影响,以发育冲积扇沉积为主,中东部区域地形相对较缓,以发育辫状河沉积为主;q2砂层组时期,填平补齐作用使得西部区域地形逐渐变缓,整个研究区不再发育冲积扇沉积,辫状河沉积覆盖在整个研究区域。q1砂层组时期,研究区大部分地区淹没于湖平面之下,主要发育三角洲平原和三角洲前缘沉积。更多还原

【Abstract】 Based on the outcrop, core, well log interpretation, this paper studies the sedimentary facies of the upper Jurassic Qigu Formation in northwestern Junggar Basin and establishes the sedimentary system evolution. The results indicate that Qigu Formation in the study area can be divided into three sandstone groups as q1, q2, and q3. There are three types of sedimentary facies, including alluvial fan, braided river, and delta, which may be further divided into 7 subfacies and 10 microfacies. During the q3 sandstone group deposition period, the western part of the area was mainly affected by the Karamay fault, with the development of alluvial fan. The middle and eastern part of the area was relatively flat. The braided river dominated in this period. During the q2 sandstone group deposition period, the topography in the western part gradually softened due to filling-up effect. the braided river covered the entire study area instead of the alluvial fan. Then during the q1 sandstone group deposition period, most of the study area submerged below the lake level, where the deltaic plain and deltaic front sedimentary facies developed.更多还原