塔中Ⅰ号坡折带中古3井区在晚奥陶世良里塔格组沉积时期,处于碳酸盐台地的边缘相带,发育粒屑滩、灰泥丘及礁丘等亚相。研究表明,研究区沉积相的横向变化特征总体上表现为沿Ⅰ号坡折带发育礁滩复合体,往内侧则主要形成丘滩复合体。在纵向演化上丘滩体具有由内带向外带的发育前缘规律,晚期的丘滩体前积作用明显。 During the deposition of the Lianglitage Formation of Late Ordovician during the Late Ordovician Lianglitage Formation, the Middle 3 well in Tazhong Ⅰ slope break zone is located in the marginal facies of the carbonate platform and develops subfacies of grain-dikes beaches, lime-mud mounds and reef mounds. The results show that the lateral variation of sedimentary facies in the study area generally shows that the reef-shoal complex develops along the slope of No. Ⅰ slope, and the mound-beach complex mainly forms inside. In the longitudinal evolution of the upper body of the beach from the band to the outer zone of the development of the law of the front, the early role of the beach before the plot is obvious.