Geochronological and Geochemical evidence of amphibolite from the Hualong Group, northwest China: Implication for the early Paleozoic accretionary tectonics of the Central Qilian belt

Wang, Tao; Wang, Zongqi; Yan, Zhen; Ma, Zhenhui; He, Sheng-fei; Fu, Changlei; Wang, Dongsheng

doi:10.1016/j.lithos.2016.01.012

Cited by 44 publications

(29 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This evolution involved the northward subduction of the Qilian oceanic crust beneath the Central Qilian Terrane, forming the Tadong pluton and SSZ‐type ophiolites between the early Cambrian and the Late Ordovician (Fu et al, ; Song et al, ; Wang et al, ). This Southern Qilian ocean slab then underwent continuous northward subduction, forming arc‐related magmatic rocks such as the Huangcaoshan pluton between the Early to Middle Ordovician (Wang et al, ). The Qilian Ocean finally closed during the Late Ordovician (Yang et al, ).…”

Section: Discussionmentioning

confidence: 99%

“…The evolutionary history and tectonic attributes of the South Qilian Belt is important for reconstructions of the Qilian Belt. However, the majority of previous research in this area has focused on igneous rocks on the North Qilian Belt (Song et al, ; Wang et al, ; Wu et al, ), the ophiolites on the South Qilian Belt (Fu et al, ; Fu et al, ; Fu et al, ), and the Hualong Complex (Wang et al, ; Yan et al, ). The intrusives in South Qilian Belt is limited (Yang et al, ; Yong & Yuanc, ).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Geochronology and geochemistry of early Palaeozoic intrusive rocks in the Lajishan area of the eastern south Qilian Belt, Tibetan Plateau: Implications for the tectonic evolution of South Qilian

et al. 2018

View full text Add to dashboard Cite

The Lajishan area, located in the South Qilian orogenic Belt, north‐eastern Tibetan Plateau, contains a compositionally diverse range of Cambrian to early Ordovician felsic intrusions that reflect the early Palaeozoic tectonic evolution of the Central Qilian Belt. This paper presents new geochemical, Sr─Nd and Lu─Hf isotopic, and zircon U─Pb data for the Tadong, Huangcaoshan, and Yindonggou plutons in the eastern Lajishan area. LA‐ICPMS U─Pb ages of 517.4 ± 1 Ma for the Tadong pluton which is the first find Late Cambrian granitoids in this area, 467 ± 1 Ma for the Huangcaoshan pluton and 446 ± 1 Ma for the Yindonggou pluton. The new data indicate that the Tadong pluton and Huangcaoshan pluton belong to I‐type granite. Their A/CNK values range from 0.82 to 1.03, suggesting a close relationship with I‐type granitoids. Their trace‐element geochemical characteristics include enrichments in the LILEs, pronounced depletions in Nb and Ta, enrichment of the LREEs relative to the HREEs, and Eu anomalies. These features are similar to those of I‐type volcanic‐arc magmas. Combined with Hf and Sr─Nd isotopic data, The Tadong pluton generated by the mixing of melts was derived from the partial melting of the Precambrian basement and mantle‐derived magmas. The Huangcaoshan pluton was derived from juvenile crust with contamination. The Yindonggou pluton shows A‐type characteristics, their A/NCK is 0.88–1.07, and 10000 × Ga/Al is higher than 2.6. They were characteristic with high Sr, low Y, low Yb, and enriched LREE. Combined with Hf and Sr─Nd isotopic data, the Yindonggou pluton was generated by the partial melting of oceanic slab material and was crustally contaminated associated with slab breakoff. Combined previous research suggests that Tadong pluton and Huangcaoshan pluton formed from southern subduction of the South Qilian ocean into the Central Qilian Belt; the Yindonggou pluton formed in collisional setting.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Geochronology and geochemistry of early Palaeozoic intrusive rocks in the Lajishan area of the eastern south Qilian Belt, Tibetan Plateau: Implications for the tectonic evolution of South Qilian

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The numbers indicate the degree of crustal contamination. Data source: Cambrian picrite in the regional Yongjing terrane from Y. Zhang et al (); metamorphosed basaltic rocks from the Hualong Group from T. Wang et al (); Xiashitang intrusion from Z. Zhang (). The calculated parameters of Sr (ppm), 87 Sr/ 86 Sr ( i ) , Nd (ppm), and εNd ( t ) are 320, 0.716, 27 and −10.8 for the upper crust and 348, 0.709, 11 and −7.6 for the lower crust, respectively [Colour figure can be viewed at wileyonlinelibrary.com]…”

Section: Discussionmentioning

confidence: 99%

Petrogenesis of the Fe–P–REE mineralized Shangzhuang ultramafic intrusion in the Lajishan tectonic belt, South Qilian Belt: Implications for mantle metasomatism and tectonic setting

et al. 2017

View full text Add to dashboard Cite

The Shangzhuang ultramafic intrusion in the Lajishan tectonic belt, South Qilian Belt, is mainly composed of serpentinite, biotite clinopyroxenite, apatite clinopyroxenite, and hornblendite. Zircon grains selected from biotite clinopyroxenite have distinctly oscillatory and sector zoning and yield a weighted average 206Pb/238U age of 492.6 ± 4.1 Ma, which can be considered as the crystallization age of the Shangzhuang intrusion. Initial 206Pb/204Pb and 87Sr/86Sr ratios of the intrusion suggest an enriched mantle I source origin. Rocks from the intrusion have Rb/Cs from 16 to 29 and Nb/U from 0.2 to 11.7, different from mid‐ocean ridge basalt and ocean island basalt from the convecting mantle, suggesting a subcontinental lithospheric mantle source. In comparison with Sr–Nd isotopes of the regional 456‐ to 441‐Ma mafic intrusions and basic volcanic rocks, a gradually decreasing trend of εNd(t) values from +0.90 via −0.86 to −2.57 from 493 to 441 Ma argued that the subcontinental lithospheric mantle source of the Shangzhuang intrusion was progressively enriched by mantle metasomatism in the Early Palaeozoic. The elevated (Tb/Yb)N ratios of the Shangzhuang intrusion and positive correlations between light rare earth elements (La and Nd) and P2O5 of metamorphosed basalts from the regional Hualong Group imply that the source region was an apatite‐bearing garnet‐facies peridotite as a result of modal metasomatism. In general, the Shangzhuang intrusion was formed due to the northward subduction of the Proto‐Tethys Ocean underneath the Qilian Block during late Cambrian. Together with the ~491‐Ma regional ophiolites, we suggest that the Early Palaeozoic magmatism in the Lajishan belt was formed in a subduction zone, rather than intracontinental rifting or mantle plume settings.

show abstract

“…Moreover, the Dehsard mafic (Winchester and Floyd, 1977). As an alteration-independent index for geochemical diversity, Zr concentration implements a good correlation with other elements and can be used to test their mobility (Pearce et al, 1992;Liu et al, 2012b;Wang et al, 2016). Hence, using Zr as a fractionation index, increasing FeO/MgO alongside decreasing MgO, Cr and Ni indicate mafic fractionation (olivine and/or pyroxene) ( Winchester and Floyd (1977) modified by Pearce, 1996]; (b) TiO 2 versus Zr/P 2 O 5 × 10,000 (after Winchester and Floyd, 1976).…”

Section: Geochemical Characteristicsmentioning

confidence: 99%

“…Also in the Nb/Th versus La/Nb diagram (Figure 7c) most of the samples plot in the field of arc volcanic rocks or magmas that may have been polluted by crustal source components (Pearce, 1983;Wang et al, 2016). The plot of Dehsard mafic volcanic rocks in the Nb/ Ta versus Nb diagram (Figure 7d) clearly shows the role of fractional crystallization trend and the input of sediment constituent in the magma origin (Caulfield et al, 2008;Wang et al, 2016). In addition, the La/Nb ratio greater than 1 in the Dehsard mafic volcanic rocks suggests their derivation from a lithospheric mantle source (DePaolo and Daley, 2000;Etruk et al, 2017).…”

Section: Source Of Mafic Volcanic Rocksmentioning

confidence: 99%

Geochemistry and source characteristics of Dehsard mafic volcanic rocks in the southeast of the Sanandaj–Sirjan zone, Iran: implications for the evolution of the Neo-Tethys Ocean

Nazemei¹,

Arvin²,

Dargahi³

2018

Turkish J Earth Sci

View full text Add to dashboard Cite

The Late Jurassic-Early Cretaceous Dehsard mafic volcanic rocks crop out in the southeastern Sanandaj-Sirjan Zone (SSZ), composed primarily of basalts and basaltic andesite with subordinate dolerite. They are influenced to some degree by hydrothermal alteration under zeolite-greenschist facies. Using fairly immobile trace elements, the mafic volcanic rocks show subalkaline (tholeiitic) affinities. They commonly have similar designs with somewhat strong enrichment in light rare earth elements (LREEs) and large ion lithophile elements (LILEs) and depletion in high field strength elements (HFSEs; e.g., Nb, Ta, Ti) and nearly flat heavy rare earth element (HREE) patterns. The negligible or absence of negative Eu anomalies indicate that plagioclase played an insignificant role during magma evolution. The low La/Nb (1.03-2.31) and Nb/Y (0.12-0.46) ratios, relatively high Zr/Y (4.03-8.18) and Th/Ta (2.25-9.64) ratios, steady enhanced normalized patterns, and moderate La/Nb ratios hint at an island arc and most likely a back-arc basin environment for the formation of Dehsard mafic volcanic rocks. The arc magma resulted from partial melting of depleted mantle source that experienced assimilation and fractional crystallization and was enhanced by melts of subducted sediments or contribution of slabderived fluids in an intraoceanic subduction environment in the Neo-Tethyan Ocean. Therefore, the presence of an island arc setting (Dehsard island arc) must be investigated in the south of the SSZ prior to the Late Jurassic-Early Cretaceous as the Neo-Tethys oceanic crust was subducting north beneath the southern margin of the Central Iranian Microcontinents. The later collision of the arc with SSZ led to tectonic proximity of the Dehsard mafic volcanic rocks to SSZ components.

show abstract

Geochronological and Geochemical evidence of amphibolite from the Hualong Group, northwest China: Implication for the early Paleozoic accretionary tectonics of the Central Qilian belt

Cited by 44 publications

References 56 publications

Geochronology and geochemistry of early Palaeozoic intrusive rocks in the Lajishan area of the eastern south Qilian Belt, Tibetan Plateau: Implications for the tectonic evolution of South Qilian

Geochronology and geochemistry of early Palaeozoic intrusive rocks in the Lajishan area of the eastern south Qilian Belt, Tibetan Plateau: Implications for the tectonic evolution of South Qilian

Petrogenesis of the Fe–P–REE mineralized Shangzhuang ultramafic intrusion in the Lajishan tectonic belt, South Qilian Belt: Implications for mantle metasomatism and tectonic setting

Geochemistry and source characteristics of Dehsard mafic volcanic rocks in the southeast of the Sanandaj–Sirjan zone, Iran: implications for the evolution of the Neo-Tethys Ocean

Contact Info

Product

Resources

About