Late Paleozoic volcanic record of the Eastern Junggar terrane, Xinjiang, Northwestern China: Major and trace element characteristics, Sr–Nd isotopic systematics and implications for tectonic evolution

Geochronology and Geochemistry of Igneous Rocks from the Laoshankou District, North Xinjiang: Implications for the Late Paleozoic Tectonic Evolution and Metallogenesis of East Junggar

“…Over the past several decades, considerable research has been undertaken to clarify the tectonic evolution of the East Junggar and concluded that it is closely associated with the evolution of the Paleo-Asian Ocean. Despite significant advances, some critical problems remain unsolved, including two main issues: (1) whether the tectonic setting of the northern margin of East Junggar in the Late Paleozoic was an island arc (Windley et al, 2002;Zhang et al, 2009) or an active continental margin (Chen and Jahn, 2004)? and (2) whether the northern margin of East Junggar was formed by the northward subduction of the Junggar Ocean (Wan et al, 2011;Zhang et al, 2009) or the southward subduction of Kuerti-Erqis Ocean, a branch of the Paleo-Asian Ocean Xu et al, 2001Xu et al, , 2013?…”

The Paleozoic tectonic evolution and metallogenesis of the northern margin of East Junggar, Central Asia Orogenic Belt: Geochronological and geochemical constraints from igneous rocks of the Qiaoxiahala Fe-Cu deposit

“…Diagrams of (a) Nb/Y vs. Zr/TiO 2 ⁄0.0001 (Winchester and Floyd, 1977), (b) Ta/Yb vs. Ce/Yb (Pearce, 1982), (c) K 2 O vs. Na 2 O, (d) TAS (Middlemost, 1994), (e) A/CNK vs. A/ NK (Maniar and Piccoli, 1989) and (f) SiO 2 vs. AR (Wright, 1969). Lu, 2012;Zhang et al, 2009). Data of volcanic rocks in the Qiaoxiahala deposit are from Chai et al (2012).…”

“…1a). Despite decades of research, its Early Devonian to Late Carboniferous tectono-metallogenic evolution is still far from clear, with the major debate focusing mainly on: (1) whether the Devonian tectonic setting was an island arc (Windley et al, 2002;Zhang et al, 2009), active continental margin (Chen and Jahn, 2004), rift (Wei and Ni, 1990) or mantle plume ; (2) whether the orogenic activities between the Siberian plate (Altay terrane) and the Kazakhstan-Junggar block (Junggar terrane) were completed in the Early Carboniferous (Tong et al, 2012), Late Carboniferous (T. or Permian (B. C.…”

Magmatic sequences in the Halasu Cu Belt, NW China: Trigger for the Paleozoic porphyry Cu mineralization in the Chinese Altay–East Junggar

“…Moreover, the widespread basic to intermediate volcanic and intrusive rocks in Junggar region, which are characterized with geochemical arc affinities Zhang et al, 2008), indicate a subduction tectonic setting. Besides, Zhang et al (2009b) suggested that the Middle Devonian Beitashan Formation, which comprises dominantly tholeiite to calc-alkaline rocks and is characterized by remarkably negative Nb, Ta and Ti anomalies, MORB-like HFSE ratios (Zr/Nb and Sm/Nd) and high εNd(t) values (6.4-7.3), was formed in an island arc setting. This is consistent with the data for Halasu because the whole-rock geochemistry features demonstrate that the arc-related REE patterns and negative anomalies of Ta, Zr and Hf, especially the marked Nb anomalies (Fig.…”