Geochronology and geochemistry of igneous rocks from the Kongling terrane: Implications for Mesoarchean to Paleoproterozoic crustal evolution of the Yangtze Block

Major element, trace element, and Sr-Nd-Pb isotopic compositions of Cenozoic diabase in southeastern China provide insights into the nature of their mantle sources and processes. The diabases are alkaline in lithochemistry (Na 2 O + K 2 O = 4.37-5.19 wt.%) and have overall oceanic island basalt-like trace element patterns, without negative Nb-Ta anomalies. In addition, they are characterized by lower La/Nb (<1.5) and La/Ta (<22), and higher Ce/Pb (>15) and Nb/U (>30) ratios, indicating an origin in the asthenospheric mantle. The relatively lower 143 Nd/ 144 Nd (0.512632-0.512648) and 206 ), but intermediate 87 Sr/ 86 Sr (0.7061-0.7063) ratios of the diabases are similar to enriched mantle type 1, suggesting crustal contamination or mixing with metasomatized lithsopheric mantle. However, the low Th and U contents and lack of correlations of Nd isotope compositions and MgO preclude significant crustal contamination. Alternatively, the moderate TiO 2 contents (2.01-2.09 wt.%) and high Cr concentrations (>240 ppm) suggest interaction between asthenosphere-derived melts and metasomatized lithospheric mantle. Petrological modelling suggests that the diabases were generated from a low degree (~3-5%) of partial melting of lherzolite with~2-3% garnet. Jiangxi diabase was generated in a within-plate extensional regime, probably related to the far effect of the Himalaya-Tibetan orogen.

show abstract

“…Overall, these patterns are distinct from the tholeiitic diabases from Kongling (Li et al 2014) (Figures 1(a), 5(a), and (b)).…”

Section: Geochemistrymentioning

confidence: 83%

Petrogenesis and mantle source characteristics of Cenozoic alkaline diabase, Jiangxi Province, southeastern China

Lin

Xing

et al. 2014

International Geology Review

Self Cite

View full text Add to dashboard Cite

show abstract

“…2.9 Ga amphibolites in the Kongling Complex and the ca . 2.87 Ga granites in the Yangpo Group (L. M. Li et al, ; Z. J. Wang et al, ). These characteristics indicate that the Yangtze Block probably experienced significant recycling of crustal material with additional continental crustal growth during ca .…”

Section: Discussionmentioning

confidence: 99%

“…Recent research has revealed that the Yangtze Block was deemed to probably have been affected by two apparent Palaeoproterozoic magmatic events during ca . 2.5–2.3 and 2.1–1.6 Ga intervals (Han et al, ; Hui et al, ; L. M. Li et al, ; Peng et al, , ; Z. J. Wang et al, ; Q. Xiong et al, ; Yin et al, ).…”

Section: Discussionmentioning

confidence: 99%

“…1.9–1.8 Ga mafic dyke and A‐type granite from the Kongling Complex and the Yangpo Group in the north, and the ca . 1.7–1.6 Ga diabase and tuff from the Dongchuan Group and the Dahongshan Group in the southwest (Greentree & Li, ; Q. Xiong et al, ; Peng et al, , 2012; W. H. Sun, Zhou, et al, ; X. F. Zhao & Zhou, ; Yin et al, ; L. M. Li et al, ; Z. J. Wang et al, ; Han et al, ). The Yangtze Block has been probably involved in the assemblage and break‐up processes of the Palaeoproterozoic supercontinent Columbia during the ca .…”

Section: Discussionmentioning

confidence: 99%

“…B. Wu et al, ; S. B. Zhang et al, , ; Zheng et al, ; Zhou et al, ), and a series of collisional and post‐collision extensional magmatism during ca . 2.1–1.6 Ga in the Palaeoproterozoic time (Han et al, ; Hui et al, ; L. M. Li et al, ; Peng et al, , ; Z. J. Wang et al, ; Y. B. Wu et al, ; Q. Xiong et al, ; Yin et al, ; Zhou et al, ).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Geochronology and geochemistry ofca. 2.48 Ga granitoid gneisses from theYudongzi Complexin the north‐westernYangtze Block,China

et al. 2018

View full text Add to dashboard Cite

The Early Precambrian magmatism in the Archean–Palaeoproterozoic basement Yudongzi Complex is critical for understanding the early crustal formation and evolutionary history of the Yangtze Block in the South China Craton. In this paper, combined zircon UPb geochronological, zircon Hf isotopic, and whole‐rock geochemical studies are carried out on the granitoid gneisses from the Yudongzi Complex, north‐western Yangtze Block. The magmatic zircons from the granitoid gneiss yield a UPb upper intercept age of 2,477±18 Ma, interpreted as the crystallization age of the granitoid gneiss. The granitoid gneiss samples are characterized by high Al2O3 contents, moderate to high Sr/Y, (La/Yb)N and Na2O/K2O ratios, no obvious Eu and Sr anomalies, and depleted Nb, Ta, and Ti values that are similar to those of Archean trondhjemite–tonalite–granodiorite (TTG) suites, indicating that the investigated rocks belonging to TTG‐series rocks. They display pronounced enriched‐LREE patterns with high La/Yb values and relatively high Zr/Sm and Eu/Eu* but low Nb/Ta and Dy/Yb ratios, implying that these rocks were formed by partial melting within amphibolite‐facies conditions with mainly residual amphibole, garnet, and accessory rutile in the magma source. These rocks also display apparently low MgO, Mg#, Ni, and Cr contents, suggesting derivation from partial melting of thickened ancient lower crust. Zircon εHf(t) values from the granitoid gneiss sample vary from −10.1 to −6.9 with TDM2 of ca. 3.59–3.40 Ga, what demonstrates their crustal source nature as well. Thus, taking all these factors together, we propose that the ca. 2.48 Ga granitoid gneisses in the Yudongzi Complex might have been produced by partial melting of ancient crust material under amphibolite‐facies conditions, with primarily residual assemblages of amphibole, garnet, and attached rutile. Taking together our new data and such from previous studies, the Yangtze Block has been probably involved into a significant reworking of ancient crust event during the Early Palaeoproterozoic time.

show abstract

Precambrian tectonic affinity of theNorthQinlingMicrocontinent: Constraints from the discovery ofMesoproterozoic magmatic zircons in theQinlingGroup

Cao

Zhao

et al. 2017

Geological Journal

View full text Add to dashboard Cite

This paper presents new results on zircon U–Pb dating of a two‐mica schist from the Qinling Group in the core of the North Qinling Orogenic Belt (NQB), Central China, with the aim of constraining the formation time of the Qinling Group, and the tectonic affinity of the North Qinling Microcontinent. Zircon U–Pb dating indicates that the protolith of the metasedimentary rock in the Qinling Group was deposited later than ~1502 Ma. The Qinling Group in the NQB represents a long‐lived unit, and its formation age can be constrained to the period between the Paleoproterozoic and early Neoproterozoic. The zircon age populations of the studied sample can be divided into two major populations of 1559–1642 and 1470–1548 Ma, and one subordinate population of 1717–1794 Ma, indicating their provenances were mainly attributed to the NQB and subordinately from the North China Craton (NCC) and the Yangtze Craton (YZC). And the distribution of the early Neoproterozoic magmatic events and the Nd–Pb whole‐rock isotopes, zircon Hf isotopes, and trace element compositions of the Precambrian basement rocks in the NQB is significantly different from those in the NCC and YZC, indicating that the NQB cannot be a southern sector of the NCC, or a northern sector of the YZC, and was an independent microcontinent from the Paleoproterozoic to the early Neoproterozoic.

show abstract

Geochronology and geochemistry of igneous rocks from the Kongling terrane: Implications for Mesoarchean to Paleoproterozoic crustal evolution of the Yangtze Block

Cited by 138 publications

References 92 publications

Petrogenesis and mantle source characteristics of Cenozoic alkaline diabase, Jiangxi Province, southeastern China

Petrogenesis and mantle source characteristics of Cenozoic alkaline diabase, Jiangxi Province, southeastern China

Geochronology and geochemistry ofca. 2.48 Ga granitoid gneisses from theYudongzi Complexin the north‐westernYangtze Block,China

Precambrian tectonic affinity of theNorthQinlingMicrocontinent: Constraints from the discovery ofMesoproterozoic magmatic zircons in theQinlingGroup

Contact Info

Product

Resources

About