Porphyry Cu-Mo deposits in the eastern Xing’an-Mongolian Orogenic Belt: Mineralization ages and their geodynamic implications

Abstract

The eastern Xing'an-Mongolian (Xing-Meng) Orogenic Belt (XMOB) is one of the important areas of porphyry copper (Cu)-molybdenum (Mo) deposits in China.However, studies on the exact ages of mineralization and their geodynamic significance are very limited. In this study, granodioritic rocks from the Duobaoshan Cu deposit and Daheishan Mo deposit were selected to make zircon SHRIMP U-Pb analyses in order to constrain their mineralization ages. Geochronological data indicate that two episodes of mineralization took place in the Duobaoshan Cu deposits. The granodiorite related to the Duobaoshan porphyry Cu deposit was formed in the Early Paleozoic with zircon U-Pb age of 485±8 Ma, whereas the granodiorites related to the Sankuanggou skarn-type Cu deposit were emplaced in the Jurassic with zircon U-Pb ages of 176±3 and 177±3 Ma. In the Daheishan area of Jilin Province, the emplacement age of the granodiorite porphyry related to the porphyry Mo deposit was dated at 170±3 Ma, and the unmineralized monzogranite at 178±3 Ma. Therefore, two episodes of Cu-Mo mineralization were developed in the eastern XMOB, at ~485 Ma and ~175 Ma, respectively. Based on the geological history and spatial-temporal distribution of the granitoids in northeastern (NE) China, it is proposed that the Duobaoshan Cu deposit was related to the collision of the Xing'an and Erguna blocks in the Early Paleozoic, and the Sankuanggou Cu and Daheishan Mo deposits were related to subduction of the Paleo-Pacific plate during the Jurassic.

Geochronology and geochemistry of early Paleozoic igneous rocks from the Zhangguangcai Range, northeastern China: Constraints on tectonic evolution of the eastern Central Asian Orogenic Belt

“…493 and 467-445 Ma; Zhang et al, 2014;Pei et al, , 2016 as well as in the Xing'an block (ca. 480-450 Ma; Ge et al, 2007b;Wu et al, 2011;She et al, 2012;Wu et al, 2015), the Erguna block (ca. 500-446 Ma; Ge et al, 2005Ge et al, , 2007aWu et al, 2005;Sui et al, 2006;Wu et al, 2011;She et al, 2012;Zhao et al, 2014), and the Russian part of the Bureya block (ca.…”

SIMS zircon U–Pb and molybdenite Re–Os geochronology, Hf isotope, and whole-rock geochemistry of the Wunugetushan porphyry Cu–Mo deposit and granitoids in NE China and their geological significance

“…Located primarily on the Xing'an and Erguna blocks, the northern part of the Great Xing'an Range in NE China is known for large exposures of Mesozoic granites and volcanic rocks (Fan et al, 2003;Ge et al, 2005;F. Wang et al, 2006;Ge et al, 2007;L.C. Zhang et al, 2008), and also is an important polymetallic metallogenic belt hosting different types of hydrothermal deposits (Liu et al, 2001;Mao et al, 2003;D.G.…”

Early Paleozoic subduction of the Paleo-Asian Ocean: Geochronological and geochemical evidence from the Dashizhai basalts, Inner Mongolia

“…high Sr and low Y and HREE concentrations) in the Hinggan Mountains; they considered these rocks as melts of contemporaneous subducting oceanic slab [20] . Ge et al [28,29] reported a few granodioritic intrusions associated with Cu-Mo mineralization and an early Paleozoic gabbro intrusion in the Hinggan Mountains; they proposed that these rocks were respectively formed by slab subduction and post-collisional extension. Some early Paleozoic magmatic zircons were also found in the metamorphosed subduction-accretion complexes [30][31][32] .…”