N style="FONT-FAMILY: ’Times New Roman’; FONT-SIZE: 14pt; mso-font-kerning: 1.0pt; mso-fareast-font-family: 宋体; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA" lang=EN-US> nChDivSummary name="EnDivSummary">Recent studies showed that the Shijihe area is an important polymetallic metallogenic belt in western part of namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />n">North n">Qilian n">Mountains in ntry-region w:st="on">n">Chinantry-region>. However, geological study degree is very low due to its remoteness and poor conditions. The Lavas of Shijihe area consists of actinolitite hornstone and spilite. The geochemical characteristics of metamorphic basic lava with flat REE distribution patterns, the contents of HFSE similar to N-MORB and εNd(0)=+9.03~+9.42 ( except the sample 08p1) manifest that the rocks belong to the tholeiitic basalt series. Sr isotope characteristics indicate that Sr isotopic composition of the rocks was altered because of the metamorphism of the rock instead of the interfused crust. Sm-Nd isochron age is (481±20) Ma.