In the overlying basalt, there is high dip and wide tension fissure zone, which is combined with surface of unconformity which is as basal sliding face, to form loosening rock mass.
在上覆玄武岩层中见有高倾角的宽张裂隙带，与不整合面一起构成松动岩体，不整合面为底滑面。
2
Vertically, rocks near the unconformity appear layers which are in turn semi-weathering rock, weathering clay bed and basal conglomerate.