A Neoproterozoic seamount in the Paleoasian Ocean: Evidence from zircon U–Pb geochronology and geochemistry of the Mayile ophiolitic mélange in West Junggar, NW China

Accreted seamounts in North Tianshan, NW China: Implications for the evolution of the Central Asian Orogenic Belt

“…Moreover, Hirano et al (2006) proposed that the small alkaline volcanoes erupt along lithospheric fractures in response to plate flexure White and Duncan (1996), Louisville from Vanderkluysen et al (2014), OIB and MORB compositions are from Sun and McDonough (1989). during subduction. In our previous studies we discussed the occurrences of alkaline basalts hosted by ophiolitic mélanges in the West Junggar and suggested that the plume-related magmatism developed during the evolution of the Junggar ocean as well as paleo-Asian Ocean (Yang et al, 2012b(Yang et al, , 2013(Yang et al, , 2015. Safonova and Santosh (2014) also considered that the OIB-bearing units of the CAOB and the Western Pacific formed in relation to two superplumes: the Asian with age of the Late Neoproterozoic and the Pacific with age of the Cretaceous.…”

“…The vast accretionary complexes of the CAOB contain a significant proportion of more-enriched basalts (Yang et al, 2015), similar in composition to modern-day ocean island basalts (OIB). On the basis of their geochemistry and nature of associated sediments many of these enriched basalts have been interpreted as the accreted remnants of seamounts (e.g., Safonova and Santosh, 2014;Yang et al, 2012aYang et al, , 2012bYang et al, , 2013Yang et al, , 2015. However, since accreted seamounts generally get caught up in ophiolitic mélange belts they have undergone intense deformation, so can easily be misinterpreted as "classic" ophiolitic units (cf.…”

Spatial–temporal framework for the closure of the Junggar Ocean in central Asia: New SIMS zircon U–Pb ages of the ophiolitic mélange and collisional igneous rocks in the Zhifang area, East Junggar

“…The 320 Ma volcanic rocks in the Kalamaili area are bimodal . The volcanic rocks in the Luliang rifting basin and Wucaiwang area adjacent to the Kalamaili ophiolite belt are also bimodal and post-collisional Yang et al, 2010d;He et al, 2013a;Xu et al, 2015) and have ages from 350 to 300 Ma (Tan et al, 2009;Su et al, 2012;Yang et al, 2012d;Zhang et al, 2013). There are great numbers of granitoids, including granodiorites, monzogranites and alkali granites, with zircon U-Pb ages ranging from 333 to 268 Ma with a peak age of approximately 303 Ma within and adjacent to the MTDKZD ophiolite belt ( Fig.…”

Geochemistry, zircon U–Pb ages and Lu–Hf isotopes of early Paleozoic plutons in the northwestern Chinese Tianshan: Petrogenesis and geological implications

“…These rocks show strong island arc affinities and are most likely related to subduction of the Junggar Ocean (Xu et al, 2012). Because these calc-alkaline rocks occur in the northern side of the Neoproterozoic to early Paleozoic Tangbale and Mayile ophiolites and gabbros that yielded zircon ages of 531 ± 15 Ma and 572 ± 9 Ma, respectively (Jian et al, 2005;Yang et al, 2012), it is suggested that the beginning of northward subduction of the Junggar Ocean likely began in the late Cambrian. Therefore, bidirectional subduction is reasonable to assume for the subduction polarity of the Junggar Ocean in the early Paleozoic (Fig.…”