A COMPATIVE STUDY ON GEOLOGY AND GEOCHEMISTRY AND MINERALIZATION OF THE MO-BEARING AND AU-BEARING GRANITE SERIES ON THE NORTH CHINA PLATFORE
Chai Sheli;Cai Jing;Zou Zurong(Changchun University of Earth Sciences)(Shanghai Normal University )
A geological and geochemical study has been made of the Mo-bearingand the Au-bearing granite series. The Mo-bearing granite series can be grouped intotwo sub-rock series being the moderately evolved Cu and Mo-bearing granodiorite withSiO_2 52%～70%, DI 44～84, strong enrichment LREE(La/Yb l9.5～30.4),Yb 3.99～6.78 and δ Eu 0.74～1.03 and the highly evolved Mo-bearing granite with SiO_2 61～76%,DI 63～93 , variable LREE(La/Yb 2.44～86.4) and Yb l,57～10.29 and δ Eu0.28～0.85 in light of their mineralizatinns. The Au-bearing granite series is belongedto highly evolved granite rock series with SiO_2 54～75%, DI 57～93, variable LREE(La/Yb.67～55.13),Yb 2.21～17.47 and δ Eu 0.28～1.36.Major and traceelements and isotopes of Strotitim and Oxygen show that the Mo-bearing rock serieswere mainly derived from the melting of the low crust materials with additional input ofthe maiitle materials,and the Au-bearing derived from low crust materials.Au ores were associated with magmatic hydrothermalsolutions fractiontioned in the deep crust and formed water一phile deposits.