喀左盆地九佛堂组沉积特征及演化研究

喀左盆地是辽宁西部晚中生代裂陷盆地，充填地层为九佛堂组。通过对野外露头的颜色、结构、原生沉积构造等岩性特征及其空间配置和古生物化石组合的研究，以及室内编图综合分析，从九佛堂组中识别出辫状河三角洲相、湖泊相、湖泊重力流相和扇三角洲相4种沉积相。其中，湖泊相是九佛堂组的主体，呈长条形状发育于各个凹陷的中间部位；辫状河三角洲相主要发育于大城子凹陷和四官营子凹陷的西北侧；扇三角洲主要发育于四官营子凹陷和梅勒营子凹陷的东南侧；湖泊重力流相主要发育于喀左盆地的深湖区。受盆地沉降速率与盆地沉积充填速率相对关系的制约，九佛堂组沉积演化自早到晚表现为:湖泊扩张退积期、大湖加积期和湖泊萎缩进积期。

Sedimentary Characteristics and Evolution of Jiufotang Formation in Kazuo Basin

Kazuo basin is Late Mesozoic era rift basin in the west of Liaoning,in which Jiufotang Formation is the filling stratum. On the basis of lithologic character analysis ,such as the color,structure,primary sedimentary structure of field outcrops ,and also analysis of the spatial disposition and paleontology fossil combination,as well as drawing and integrated analysis in the laboratory,four sedimentary facies containing braided river delta facies,lake facies,lake gravity flow facies and fan delta facies are r...