Formation time of the big mantle wedge beneath eastern China and a new lithospheric thinning mechanism of the North China craton—Geodynamic effects of deep recycled carbon

Mesozoic magmatic rocks are widely distributed in the North China Craton (NCC) and are crucial to understanding the timing, location, and geodynamic mechanisms of lithospheric thinning of the NCC. In this study, we report geochronological, petrogeochemical, and Lu–Hf isotopic data for adakitic granitoids from different parts of Xiuyan pluton in the Liaodong Peninsula, aiming to constrain their magma sources, petrogenesis, and tectonic implications. The adakites are metaluminous to weakly peraluminous and are classified as high-K calc-alkaline I-type granite with Early Cretaceous zircon U–Pb ages of 129–126 Ma. They exhibit adakite-like geochemical characteristics, such as high Sr content and low Yb and Y contents, coupled with high Sr/Y and no pronounced Eu anomalies. They are enriched in Rb, U, and light rare-earth elements and are depleted in Ta, Nb, P, and Ti. The adakites from the eastern part of the pluton have low εHf(t) values (–8.5 to –4.0) with old TDM2 ages (1.57–1.31 Ga), indicating they were derived from the lower crust containing juvenile mantle-derived materials. In contrast, adakites from the northern part of the pluton have lower εHf(t) values (–19.7 to –16.6) with older TDM2 ages (2.21–2.03 Ga), indicating that they were derived mainly from an ancient crust. Our results show that both adakitic magmas were derived from partial melting of delaminated lower crust. Their relatively high MgO and Ni contents and Mg# values indicate that the melts interacted with mantle peridotites. The lower crust delamination beneath the Liaodong Peninsula resulted from paleo-Pacific plate subduction during the Early Cretaceous, which resulted in thinning of Mesozoic crust in the Xiuyan area.

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ABNORMAL TECTONOTHERMAL EVOLUTION AND ITS DYNAMIC MECHANISM IN THE EASTERN ORDOS BASIN: RESPONSE TO LITHOSPHERIC THINNING AND DESTRUCTION OF THE NORTH CHINA CRATON

10.1130/abs/2019am-330098 ◽

2019 ◽

Author(s):

Kun Yu ◽

Keyword(s):

North China Craton ◽

North China ◽

Ordos Basin ◽

Dynamic Mechanism ◽

Lithospheric Thinning ◽

The North ◽

Basin Response

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Devonian rodingite from the northern margin of the North China Craton: mantle wedge metasomatism during ocean–continent convergence

International Geology Review ◽

10.1080/00206814.2017.1365631 ◽

2017 ◽

Vol 60 (9) ◽

pp. 1073-1097

Author(s):

Chao-Nan Hu ◽

M Santosh

Keyword(s):

North China Craton ◽

North China ◽

Mantle Wedge ◽

Northern Margin ◽

The North

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Characterization and origin of the Taishanmiao aluminous A-type granites: implications for Early Cretaceous lithospheric thinning at the southern margin of the North China Craton

International Journal of Earth Sciences ◽

10.1007/s00531-015-1269-9 ◽

2015 ◽

Vol 105 (5) ◽

pp. 1563-1589 ◽

Cited By ~ 26

Author(s):

Changming Wang ◽

Liang Chen ◽

Leon Bagas ◽

Yongjun Lu ◽

Xinyu He ◽

...

Keyword(s):

Early Cretaceous ◽

North China Craton ◽

North China ◽

Lithospheric Thinning ◽

The North ◽

Southern Margin

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Separating multiple episodes of partial melting in polyorogenic crust: An example from the Haiyangsuo complex, northern Sulu belt, eastern China

Geological Society of America Bulletin ◽

10.1130/b35210.1 ◽

2019 ◽

Vol 132 (5-6) ◽

pp. 1235-1256

Author(s):

Peng Feng ◽

Lu Wang ◽

Michael Brown ◽

Songjie Wang ◽

Xiawen Li

Keyword(s):

Partial Melting ◽

North China Craton ◽

North China ◽

Eastern China ◽

Magma Ascent ◽

Magmatic Zircon ◽

Weighted Mean ◽

Heavy Rare Earth Element ◽

Orogenic Collapse ◽

The North

Abstract The exotic Haiyangsuo complex is structurally part of the Sulu belt but its contact relationship with surrounding Sulu gneisses is unexposed and therefore unknown, making its affinity uncertain. It comprises gneisses with in-source leucosomes that host minor metabasite bodies; both are cut by leucogranite dikes. In this study, we determine the timing and petrogenesis of leucosomes and leucogranites and assess the tectonic affinity of the complex based on data from gneisses and metabasites. Most zircon from gneisses and leucosomes has oscillatory-zoned cores with CL-bright overgrowth rims, but some has CL-dark cores or mantles between cores and rims. CL-dark and bright zircon yield weighted mean ages of ca. 1817–1812 Ma. CL-dark zircon has flat heavy rare earth element (HREE) patterns and crystallization temperatures of 829–875 °C, suggesting metamorphic growth, whereas rims have steep HREE patterns but a similar range of crystallization temperatures, suggesting growth from anatectic melt; εHf (t = 1813 Ma) of –18.3 to –10.8 indicates a North China Craton source. Magmatic zircon from metabasites yields ages of ca. 825 Ma, similar to those of scattered metabasite occurrences in the North China Craton. Paleoproterozoic zircon cores were scavenged during magma ascent. By contrast, zircon cores from the leucogranites yield concordant dates of 776–701 Ma, consistent with protolith ages in the Sulu belt, whereas overgrowth mantles and rims yield weighted mean ages of ca. 220 Ma and 162 Ma, respectively. Both mantles and rims host multiphase solid inclusions, representing former melt, suggesting anatexis and crystallization of zircon first during initial decompression and then during orogenic collapse of the Sulu belt; whole-rock Nd and Sr isotope compositions implicate the Sulu belt gneisses as the source of these melts. Our interpretation of these data is that the Haiyangsuo complex has an early geologic history similar to the Jiaobei terrane from the southeastern part of the North China Craton and was incorporated into the Sulu belt during Triassic collision of the Yangtze and North China Cratons. The two stages of melting relate to Upper Triassic early exhumation and Upper Jurassic late-stage orogenic collapse, during which the leucogranite magma was derived from a source similar to one elsewhere in the Sulu belt such as the subducted Yangtze Craton and not the North China Craton. This shows that during continental collisions, crust from the upper plate may be dragged into the subduction channel, deformed, and subsequently exhumed in association with partial melting of the crust.

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Upper-mantle velocity structure beneath the North China Craton: implications for lithospheric thinning

Geophysical Journal International ◽

10.1111/j.1365-246x.2009.04120.x ◽

2009 ◽

Vol 177 (3) ◽

pp. 1279-1283 ◽

Cited By ~ 95

Author(s):

Peifen Xu ◽

Dapeng Zhao

Keyword(s):

Upper Mantle ◽

North China Craton ◽

North China ◽

Velocity Structure ◽

Lithospheric Thinning ◽

The North ◽

Mantle Velocity

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Late Jurassic, high Ba–Sr Linglong granites in the Jiaodong Peninsula, East China: lower crustal melting products in the eastern North China Craton

Geological Magazine ◽

10.1017/s0016756816001230 ◽

2017 ◽

Vol 155 (5) ◽

pp. 1040-1062 ◽

Cited By ~ 21

Author(s):

LI-QIANG YANG ◽

YILDIRIM DILEK ◽

ZHONG-LIANG WANG ◽

ROBERTO F. WEINBERG ◽

YUE LIU

Keyword(s):

North China Craton ◽

Late Jurassic ◽

North China ◽

Eastern China ◽

Ultrahigh Pressure ◽

Granitic Rocks ◽

Crustal Melting ◽

Heavy Rare Earth Element ◽

The North ◽

Lower Crustal

AbstractThe Jurassic Linglong granites, intrusive into the North China Craton (NCC) in eastern China, provide a critical record of the first major episode of lithospheric-scale extension and magmatism in NE China during Mesozoic time. Our U–Pb zircon dating reveals that the Linglong granites were emplaced during 161–158 Ma, shortly after the inception of a shallow subduction of the Palaeo-Pacific plate beneath East Asia during Middle Jurassic time. These granites have high alkali contents (K2O + Na2O = 8–9 wt%), low MgO and Mg no. values and variable Cr–Ni abundances. Their relatively high Ba and Sr concentrations, relatively low heavy rare Earth element (HREE) and strongly fractionated REE patterns characterize them as high Ba–Sr granites. The negative whole-rock εNd(t) values ranging from −22.4 to −10.9 and wide-ranging zircon εHf(t) values of −39.1 to −1.5 suggest that magmas of the Linglong granites were produced by partial melting of a garnet-amphibolite-bearing lower crust of the Jiaobei Terrane and by re-melting of the Triassic ultrahigh-pressure (UHP) metamorphic rocks and alkaline suites of the Sulu Terrane. The occurrence in the granitic rocks of inherited zircons of the Neoarchaean, Palaeoproterozoic, Neoproterozoic, Palaeozoic and Triassic ages suggests that magmas of the Linglong granites interacted with the ancient crust in these terranes during their ascent. Asthenospheric upwelling, induced by the steepening and rapid rollback of the Palaeo-Pacific slab during Late Jurassic time, provided the heat source for the inferred lower crustal melting. Trench migration and thermal weakening of the crust caused extensional deformation and thinning in the eastern part of the NCC.

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Newly identified Jurassic–Cretaceous migmatites in the Liaodong Peninsula: unravelling a Mesozoic anatectic event related to the lithospheric thinning of the North China Craton

Geological Magazine ◽

10.1017/s0016756820000552 ◽

2020 ◽

pp. 1-17

Author(s):

Jin Liu ◽

Jian Zhang ◽

Chang-Qing Yin ◽

Chang-Quan Cheng ◽

Jia-Hui Qian ◽

...

Keyword(s):

North China Craton ◽

North China ◽

Thermal Anomaly ◽

Thin Layers ◽

Crustal Thickening ◽

Late Triassic ◽

Metasedimentary Rocks ◽

Lithospheric Thinning ◽

The North ◽

Liaodong Peninsula

Abstract A suite of Jurassic–Cretaceous migmatites was newly identified in the Liaodong Peninsula of the eastern North China Craton (NCC). Anatexis is commonly associated with crustal thickening. However, the newly identified migmatites were formed during strong lithospheric thinning accompanied by voluminous magmatism and intense deformation. Field investigations show that the migmatites are spatially associated with low-angle detachment faults. Numerous leucosomes occur either as isolated lenses or thin layers (dykes), parallel to or cross-cutting the foliation. Peritectic minerals such as titanite and sillimanite are distributed mainly along the boundaries of reactant minerals or are accumulated along the foliation. Most zircons show distinct core–rim structures, and the rims have low Th/U ratios (0.01–0.24). Zircon U–Pb dating results indicate that the protoliths of the migmatites were either the Late Triassic (224–221 Ma) diorites or metasedimentary rocks deposited sometime after c. 1857 Ma. The zircon overgrowth rims record crystallization ages of 173–161 Ma and 125 Ma, which represent the formation time of leucosomes. These ages are consistent with those reported magmatic events in the Liaodong Peninsula and surrounding areas. The leucosomes indicate a strong anatectic event during the Jurassic–Cretaceous period. Partial melting occurred through the breakdown of muscovite and biotite with the presence of water-rich fluid under a thermal anomaly regime. The possible mechanism that caused the 173–161 Ma and 125 Ma anatectic events was intimately related to the regional crustal extension during the lithospheric thinning of the NCC. Meanwhile, the newly generated melts further weakened the rigidity of the crust and enhanced the extension.

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