Geochronology, Geochemistry, and Lu-Hf Isotopic Compositions of Monzogranite Intrusion from the Chang’anpu Mo Deposit, NE China: Implications for Tectonic Setting and Mineralization

The Chang’anpu Molybdenum deposit occurs in the monzogranite intrusions Lesser Khingan Mountains-Zhangguangcai Mountains metallogenic belt. Previous work focused on study of deposits, including geological characteristics, mineralization time, S-Pb isotope, etc. However, systematic petrogeochemical intrusion and comparative analysis with other porphyry deposits region are lacking. Three dating samples yield LA-ICP-MS zircon weighted mean 206Pb/238U ages 174.7 ± 1.3 Ma, 174.9 1.4 174.3 1.8 respectively, indicating that magmatism occurred middle Jurassic Mesozoic. 14 show alkali rich relatively high silica content (up to 84.39%) differentiation index (DI) ranges from 86 96, showing have been subjected fractional crystallization during its evolution; depletion Ba, Sr, P, Nb, Ti, Eu also indicates rock has undergone fractionation, belong highly fractionated I-type. Positive εHf(t) values (6.72–8.85) young TDM2 (551–673 Ma) indicate formation is related partial melting juvenile lower crust, originated Mesoproterozoic depleted mantle. Mo an active continental margin setting associated westward subduction Paleo-Pacific plate beneath Eurasian plate.