Geochemistry Characteristics and Geological Significance of the Himalayan Period Granit-Porphyry in the Zaduo Region

The age of Maiduola granit-porphyry and Narigongma lithsomes, is the value of (40.86±0.4) Ma,(43.3±0.5) Ma, and they are the product of the early Stage of Yanshan, through the LAICP-M S zircon U-Pb isotopic dating, which indicate that many parts of the complex product of the times is the same lithsomes, the multi-metallic deposits of Cu, Mo, Pb, Zn, Au and Ag etc.of the porphyry types and trace elements (include REE) are found from narigongma, maiduola, yucongcongchabie, dilayi and hengsaiqing copper ore belt in the Eastern Tibet.The analytical results show that the ore-bearing porphyry and coexisting potassic plutons rocks, volcanic rocks and plutons have the same temporal-spatial distribution, uniform in the petrochemical compositions with alkali-rich (w(K₂O+Na₂O) 5%), high potassium and w(K₂O)/w(Na₂O) 1, and a strong enrichment in LILE of Sr, Ba etc and LREE.This shows the characteristics of the shoshonitic series rocks, indicating the ore-bearing porphyry of the Zaduo copper ore belt in Eastern Zaduo belongs to the typical porphyry of the shoshonitic series.