引言我省秦岭地区,分布各期构造变动中形减的岩浆岩,最老的一期是元古代黑云母角闪花岗岩;最新的是中生代燕山期黑云母花岗岩及花岗斑岩。岩石坚实致密,抗水抗风化性强,力学强度大,整体性较好,在此岩基区修建大坝,工程地质条件是较理想的, Introduction Qinling area in our province, the distribution of various periods of structural changes in the formation of magmatic rocks, the oldest one is biotite hornblendeite metamorphic; the latest is the Mesozoic Yanshanian biotite granite and granite porphyry. Rock solid and dense, strong resistance to weathering and weathering, mechanical strength, integrity is good, in this rock-based dam construction, engineering geological conditions is more ideal,