象鼻山北部边坡由废石堆、废矿堆、洪积坡积层、一般变质闪长岩、风化闪长岩、高岭土化绿泥石化闪长岩断层压碎岩、铁矿体和少量大理岩所构成。其中F_(25)断层规模较大,宽30米,延伸长而深,而且几乎与北部边坡走向一致。20～23勘探线之间的边坡,自1967年以来一直处于不稳定状态,1972年5月以后位移明显增加。1978年3月4日和10月13日,先后在21线附近72～46水平发生过局部滑落,同年8月,上部地面坡积层出现直 The northern slope of the Elephant Trunk Hill is composed of a waste rock pile, a waste ore pile, a Hongsepo deposit, a general metamorphic diorite, a weathered diorite, a kaolinized chlorite dioritic fault crushed rock, an iron ore body and a small amount of marble Constitute. Among them, the F 25 fault is large in scale and 30 meters in width, extends long and deep, and almost coincides with the northern slope. The slope between 20 and 23 exploration lines has been in an unstable state since 1967, and its displacement has obviously increased since May 1972. On March 4, 1978 and October 13, 1978, some local slippage occurred successively at the level of 72 to 46 near the line 21. In August of the same year, the upper ground slope appeared straight