由于近年来,将不整合于兰芝山岩体之上的板峪口组改属滹沱群大石岭组,后来又发现口泉一带的板峪口组与上复金刚库组变质相不一致(?),从而对其时代和归属引起争议。作者从变质相定义、透闪石与透辉石形成与转化温压条件、石榴石—黑云母矿对温度计的重新计算,确认口泉的板峪口组仍应属于五台群最低部层位。 Since the Yanyukou Formation that is not integrated with the Lanzhishan rock mass has been changed to the Dashiling Formation of the Yutuo Formation in recent years, it has been found that the metamorphic phases of the Dayukou Formation and the Shangfang Danganguantu Formation are not consistent (?) , Thus causing controversy over its age and attribution. Based on the definition of metamorphic facies, the formation and transformation of tremolite and diopside, temperature and pressure conditions, and the recalculation of the thermometer by garnet-biotite ore, it is confirmed that the plate-yukou formation of the mouth spring should belong to the lowest part of the Wutai Group .