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河北省怀来地区发育了一套由角砾岩组成的类磨拉石建造。角砾岩的角砾成分可分为三层，它们分别来自于新元古代长龙山组、古生代馒头组与张夏组，它们的堆积顺序与本区地层顺序完全一致，这种与“重矿物反剖面”原理相违背的地层序列反映了它形成于特殊的构造背景。根据岩层上下的接触关系、植物饱粉及上覆地层的同位素年龄等特征，可确定为晚三叠世杏石口组。研究表明：这套沉积是在印支运动背景下，受北东上黄旗—乌龙沟深大断裂控制的断陷盆地中，由母岩发生嗍源侵蚀、塌落等地质作用形成的一套类磨拉石建造，它可划分为两个冲积扇沉积序列，分别由泥石流相、筛积相、片流相、河道相和湖沼相等组成。沉积盆地的演化经历了三个阶段、即褶皱阶段、盆地形成阶段和盆地沉积阶段，这种构造沉积演化模式对燕山地区三叠系的研究具有重要的指导意义。
Huai Lai area in Hebei Province developed a set of breccia rock-like structure. The breccia breccia composition can be divided into three layers, they are from the Neoproterozoic Changlongshan Group, Paleozoic bread group and Zhangxia group, their stacking sequence and the sequence of this area is exactly the same, with the "heavy mineral The reverse stratigraphic sequence reflects the fact that it was formed on a special tectonic setting. According to the upper and lower contact relationship of rock strata, the fullness of the plant and the isotopic age of overlying strata, it can be determined as the late Triassic Xingshikou Formation. The results show that this sedimentary deposit is a set of geologic features of source rocks eroded and collapsed in the fault-controlled basins controlled by the Huangqi-Wulongou deep fault in the North East under the background of Indo-Chinese Movement It is divided into two alluvial fan sedimentary sequences, which are composed of debris flow facies, sieve sedimentary facies, plate flow facies, channel facies and lacustrine sediments, respectively. The evolution of the sedimentary basin has undergone three stages, that is, the fold stage, the basin formation stage and the basin depositional stage. This tectonic depositional evolution model has important guiding significance for the study of the Triassic in the Yanshan area.