Abstract:

The geochemistry characteristics of volcanic rocks in three basins indicate that the basins of Bihu, Lishui, Zhangcun have the same composition of the petrochemistry, and that the three basins mentioned above were formed in volcanic island arc. From LA-ICP-MS zircon U-Pb data of volcanic rocks in three basins，we found that the volcanic age of Chaochuan Formation in Bihu basin was (123±2) Ma, Guantou Formation in Zhangcun basin was (111±3) Ma, Tangshang Formation in Lishui basin was (95±1) Ma. The age data for those volcanic rocks in three basins show that the time of volcanic activity continued 28 Ma or so, and those data also reflect the activity continuation of Lishui-Yuyao fault.

Key words: red-bed basin, volcanic rock, LA-ICP-MS, zircon U-Pb age, Lishui, Zhejiang Province