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鞍山－本溪地区中太古代花岗质岩浆作用十分发育，形成了３．１Ｇａ立山细粒奥长花岗岩、３．０Ｇａ东鞍山片麻状花岗岩、３．０Ｇａ铁架山片麻状花岗岩和３．０Ｇａ弓长岭片麻状花岗岩等一系列花岗质岩石。岩石的εＮｄ（ｔ）分别为，立山奥长花岗岩（１０个样品）变化于－１．９６～４．２４之间，平均值为０．７６，东鞍山片麻状花岗岩（５个样品）变化于０．２６～２．７２之间，平均值为１．２６，铁架山片麻状花岗岩（５个样品）变化于－３．８５～－４．８３之间，平均值为－４．２８，弓长岭片麻状花岗岩（１个样品）为－２．５８。结合岩石的常量、微量和稀土元素特征，可以认为，立山奥长花岗岩和东鞍山片麻状花岗岩形成于地壳滞留时间不长的中酸性陆壳岩石的部分熔融，前者很可能有玄武质物质的参与。而铁架山片麻状花岗岩和弓长岭片麻状花岗岩则来自于成熟度很高的早期陆壳物质。由此可以推断，鞍山－本溪地区在中太古代以前陆壳基底就有了相当的规模，并具有很长的地壳演化历史。
The Meso-Archean granitic magmatism developed very well in Anshan-Benxi area, forming 3.1Ga Tieshan fine-grained granite, 3.0Ga Dong’anshan gneissic granite and 3.0Ga Heshanling gneissic granite. 0Ga Gongchangling gneissic granite and a series of granitic rocks. The εNd (t) of the rocks are, respectively. The variation of the Lishan granite (10 samples) varies from -1.96 to 4.24 with an average of 0.76. The variation of the Dong’anshan gneissic granite (5 samples) Between 0.26 and 2.72, with an average of 1.26, the Tiejishan gneissic granite (5 samples) varied from -3.85 to -4.83 with an average of -4. 28, Gongchangling gneissic granite (1 sample) -2.58. According to the characteristics of the rocks, trace elements and rare earth elements, it is considered that the Tethyan ophiolite and the Dong’anshan gneissic granite are partially melted in the moderately acidic continental crust with less prolonged crustal residence time, and the former are likely to have basaltic participate. The Grames granitic gneiss and Gongchangling gneiss granite from the maturity of the early continental crust material. It can be inferred that the Anshan-Benxi area had a considerable size of continental basement before the Middle Pacific and had a long history of crustal evolution.