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小秦岭地区太华杂岩以多种产状出露于表壳岩系和花岗质片麻岩中，经历了角闪岩相变质作用。其空间上的密切共生和地球化学演化特征说明它们是弧后盆地扩张不同阶段的产物。不同产状的斜长角闪岩几乎具有一致的Sm－Nd等时线年龄（2542±57）Ma，表明斜长角闪岩形成于新太古代，不支持太华杂岩时代二分为太古古和古元古代的观点。（2542±57）Ma代表了华北地由南缘新太古代张裂事件的年代。
In the small Qinling area, the Taihua complex was exposed in the epikarst facies and granitic gneisses in various occurrences and experienced amphibolite facies metamorphism. The close spatial symbiosis and geochemical evolution indicate that they are the products of different stages of backarc basin expansion. The plagioclase amphiboles with different occurrences have almost the same Sm-Nd isochron age (2542 ± 57) Ma, suggesting that amphibolite was formed in the Neoarchean andesite. And ancient yuan ancient point of view. (2542 ± 57) Ma represents the age of the Neoarchean anomaly in the North China margin from the southern margin.