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对北秦岭松树沟阿尔卑斯型超镁铁岩体接触变质带的角闪岩和斜长角闪片岩进行了全岩和单矿物氧同位素组成测定。矿物对氧同位素地质测温结果得到，角闪岩为７４５℃～７７０℃，角闪片岩为５００℃～６０５℃，均与已知的岩石学温度计结果相吻合，指示了这些变质岩内部的氧同位素平衡。靠近超镁铁岩体的角闪岩受热触变质作用影响，导致了矿物之间的氧同位素再平衡；远离超镁铁岩的角闪片岩基本未受热触变质作用影响，因此氧同位素温度代表了秦岭群区域变质岩的形成温度。角闪岩和斜长角闪片岩全岩δ１８Ｏ值为８．５～１０．３，指示变质前原岩成分可能具有中基性火成岩特征
The whole rock and single mineral oxygen isotopic compositions of amphibolite and plagioclase feldspathic rocks in the Alpine-ultramafic contact zone of the Songshugou, North Qinling are studied. The geothermometric results of mineral oxygen isotopes show that amphibolite is between 745 ° C and 770 ° C and hornblende is between 500 ° C and 605 ° C, both agree well with known petrological thermometer results, indicating that oxygen within these metamorphic rocks Isotope balance. The amphibolite near the ultramafic intrusive rocks are affected by thermal metamorphism and lead to the oxygen isotope rebalancing between the minerals. The hornblende fossils far away from the ultramafic rocks are basically not affected by thermal metamorphism, so the oxygen isotopic temperature represents Formation temperature of metamorphic rocks in Qinling Group. The δ18O values of the whole rock of amphibolite and plagioclase are from 8.5 to 10.3 , indicating that the metamorphic protolith components may have the characteristics of mafic igneous rocks