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印支运动在滨太平洋区的重要意义,一向为地质学家所关注。尤其自七十年代以来,对燕山及北京西山地区的印支运动的迹象及其性质的论述,引起了人们的重视。但对本区印支运动性质的论述,多局限于观察具体露头上下两套地层间的交角之大小。因而多数人把下侏罗统或杏石口组与下伏双泉组(属晚二叠世或部分属早三叠世)之接触关系视为平行不整合。而把北京西山古生界及双泉组(以下合并简称古生界)岩层形成的构造,简单地归因于燕山运动之结果。
The significance of the Indosinian movement in the Pacific Rim has always been of concern to geologists. In particular, since the 1970s, the discussion of the signs and nature of the Indosinian movement in Yanshan and Xishan in Beijing has drawn great attention. However, the nature of Indo-Chinese movement in this area is mostly limited to observing the angle of intersection between two sets of strata above and below the concrete outcrop. As a result, most people consider the contact relationship between the Lower Jurassic or Xingshikou Formation and the underlying Shuangquan Formation, which belongs to the Late Permian or partly to the Early Triassic, as parallel unconformities. However, the formation of the formations in the Beijing Xishan Paleozoic and Shuangquan Formation (hereinafter referred to as the Paleozoic) is simply attributed to the Yanshanian movement.