川东北开县满月甘泉剖面长兴组生物丘构成及成丘模式

川东北开县满月甘泉剖面长兴组早期发育两期生物丘，分别位于两个向上变浅的沉积旋回中上部。通过露头解剖、镜下鉴定和X衍射等手段，对该剖面生物丘构成进行精细研究发现:第一期生物丘在角砾灰岩的基础上发育，造丘生物以蓝绿藻为主；岩性为泥晶灰岩和含云灰岩；由丘基和丘核构成。第二期生物丘在生物碎屑滩的基础上发育，造丘生物早期主要为蓝绿藻和粗枝藻，后期以各类海绵和珊瑚为主；岩性为泥—微晶灰岩，局部白云岩化；发育丘基、丘核和丘顶，最终向礁骨架演化。在此基础上，探讨了两期生物丘成丘模式:前者属于低能生物丘，形成于台缘前斜坡相带内，经历了两个演化阶段；而后者属于高能生物丘，形成于台地边缘生物礁滩相带内，经历了四个演化阶段

Organic Bioherms and Their Forming Models of Changxing Formation in Manyue-Ganquan Section of Kaixian, Northeast Sichuan

Two phases of bioherms are respectively developed in the middle-upper of two descending cycles in the forepart of Changxing Formation in Manyue-Ganquan section of Kaixian, northeastern Sichuan. By the outcrop surveying, observation by microscope and diffraction of X-ray, the composition of bioherms is researched in detail. It is found that the first phase of bioherm in which the bioherm-building organisms are dominated by cyanobacteria and the lithology includes micrites and dolomitised limestone is compose...