辽河裂谷西部凹陷的南部地区,发育了三个早第三纪渐新世初期的扇三角洲砂体。该时期以断裂活动为主的裂谷构造活动,对湖盆的发展和沉积演化有着深刻影响。蓄水湖盆紧邻物源区,在大坡降的地形条件下,携带碎屑物质的河流,进入裂谷湖盆快速堆积形成的扇三角洲,除具有一般三角洲的特点外,在相带组合、砂岩体的岩石学特征、内部的结构、构造等方面又有其自己的特性。 In the southern part of the western Liaohe rift, three fan deltaic sand bodies developed in the early Oligocene are developed. During this period, the rift tectonic activity dominated by fault activity has a profound impact on the development and depositional evolution of the lake basin. The impoundment basin is close to the provenance area. Under the condition of large slope and descending, the rivers carrying detrital material enter the fan delta formed by rapid accumulation of rift lake basins. In addition to the general characteristics of the delta, Sandstone body petrological characteristics, internal structure, structure, etc. have their own characteristics.