Typical metamorphic pillow basalt is widely distributed in the Liuhang “Formation” of the Taishan “Group”, west of Tuanyuangou village, Zhangqiu, western Shandong Province. The pillows, interstitial filled with silica and carbonate, exhibit blastoporphyritic texture. The cement mainly consists of plagioclase, zoisite, hornblende, chlorite and quartz. The porphyroblasts, ususlly smaller than 0.5mm in size, are mainly composed of plagioclase, zoisite and chlorite. Electron microprobe analysis shows that, in the pillows, most albites (with An<10) in matrix, are formed during green schist facies metamorphism, but some plagioclase phenocrysts (with An>30) still remain. A SHRIMP UPb zircon age of 2707 ±9Ma was obtained for a gneissic trondhjemite, which intrudes in the Liuhang “Formation”, limiting the formation age of the Taishan “Group” no younger than 2.71Ga.