Geochronology and geochemistry of Grenville-aged (1063 ± 16 Ma) metabasalts in the Shennongjia district, Yangtze block: implications for tectonic evolution of the South China Craton

The Proterozoic−Phanerozoic tectonic evolution of the Qilian Shan, Qaidam Basin, and Eastern Kunlun Range was key to the construction of the Asian continent, and understanding the paleogeography of these regions is critical to reconstructing the ancient oceanic domains of central Asia. This issue is particularly important regarding the paleogeography of the North China-Tarim continent and South China craton, which have experienced significant late Neoproterozoic rifting and Phanerozoic deformation. In this study, we integrated new and existing geologic field observations and geochronology across northern Tibet to examine the tectonic evolution of the Qilian-Qaidam-Kunlun continent and its relationships with the North China-Tarim continent to the north and South China craton to the south. Our results show that subduction and subsequent collision between the Tarim-North China, Qilian-Qaidam-Kunlun, and South China continents occurred in the early Neoproterozoic. Late Neoproterozoic rifting opened the North Qilian, South Qilian, and Paleo-Kunlun oceans. Opening of the South Qilian and Paleo-Kunlun oceans followed the trace of an early Neoproterozoic suture. The opening of the Paleo-Kunlun Ocean (ca. 600 Ma) occurred later than the opening of the North and South Qilian oceans (ca. 740−730 Ma). Closure of the North Qilian and South Qilian oceans occurred in the Early Silurian (ca. 440 Ma), whereas the final consumption of the Paleo-Kunlun Ocean occurred in the Devonian (ca. 360 Ma). Northward subduction of the Neo-Kunlun oceanic lithosphere initiated at ca. 270 Ma, followed by slab rollback beginning at ca. 225 Ma evidenced in the South Qilian Shan and at ca. 194 Ma evidenced in the Eastern Kunlun Range. This tectonic evolution is supported by spatial trends in the timing of magmatism and paleo-crustal thickness across the Qilian-Qaidam-Kunlun continent. Lastly, we suggest that two Greater North China and South China continents, located along the southern margin of Laurasia, were separated in the early Neoproterozoic along the future Kunlun-Qinling-Dabie suture.

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Internal versus external locations of the South China Craton within Rodinia during the Cryogenian: Provenance history of the Nanhua Basin

Geological Society of America Bulletin ◽

10.1130/b35619.1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Guangyou Zhu ◽

Huichuan Liu ◽

Tingting Zhang ◽

Weiyan Chen ◽

Jianwei Xiao ◽

...

Keyword(s):

Mantle Plume ◽

South China ◽

Detrital Zircons ◽

Source Rocks ◽

Yangtze Block ◽

The South ◽

Isotopic Analyses ◽

South China Craton ◽

Late Neoproterozoic ◽

T Values

Contrasting models for internal versus external locations of the South China Craton (SCC) in the supercontinent Rodinia and associated mantle plume or ocean subduction dominated tectonic processes can be resolved by detrital zircon U-Pb dating and Lu-Hf isotopic analyses on the Cryogenian Nanhua Supergroup in the central SCC. Our results show that samples from the lower Liantuo, Tiesi’ao, and Datangpo formations of the Nanhua Supergroup show three age peaks at 2.50 Ga, 2.05 Ga, and 0.85 Ga, and those of the upper Nantuo Formation yield four peaks at 2.50 Ga, 2.05 Ga, 0.85 Ga, and 0.65 Ga. The Archean and Paleoproterozoic (1.80−2.10 Ga) zircons have εHf(t) values of −16.3 to +4.7 and −23.0 to +4.2, and may be sourced from the Kongling and Douling complexes and Paleoproterozoic intrusions in the northern Yangtze Block, respectively. Early Neoproterozoic (0.70−0.96 Ga) zircon grains show variable εHf(t) values of −20.0 to +15.0. In combination with the absence of Mesoproterozoic detrital zircons in the Nanhua Supergroup, huge volumes of Neoproterozoic granitic intrusions in the northern Yangtze Block are the potential sources for the 0.70−0.96 Ga detrital zircons. Only the siltstone of the Nantuo Formation has late Neoproterozoic (0.63−0.69 Ga) detrital zircons with high and positive εHf(t) values (+7.9 to +9.4). Several granitoid intrusions (0.63−0.68 Ga) in the Wudang and Ankang uplift of the South Qinling belt in the northern Yangtze Block provide the late Neoproterozoic detrital zircons of the Nantuo Formation. These provenance analyses of the Nanhua Supergroup indicate an interior source from the SCC, rather than an exterior source from the Laurentia and Australia cratons. The Neoproterozoic rift basins and magmatic rocks in the SCC were produced by secular episodic subductions and back-arc extensions, rather than a Neoproterozoic super-mantle plume. The SCC occupied a peripheral position adjacent to northern India in Rodinia during the Neoproterozoic. These conclusions will promote our understanding of genetic mechanism and distribution prediction of the several Cryogenian−Cambrian black-shale layers and excellent source rocks in the SCC.

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Supplemental Material: Internal versus external locations of the South China Craton within Rodinia during the Cryogenian: Provenance history of the Nanhua Basin

10.1130/gsab.s.12501830.v1 ◽

2020 ◽

Author(s):

Guangyou Zhu ◽

Huichuan Liu

Keyword(s):

South China ◽

Hainan Island ◽

Yangtze Block ◽

The South ◽

Analytical Results ◽

History Of ◽

South China Craton

Text S1: Abbreviations and reference sources of Figure 15; Figure S1: Paleogeographic environments of the western Nanhua Basin (after Jiang et al., 2011 and Bao et al., 2018); Figure S2: (A) Compiled Mesoproterozoic magmatic age data from both Yangtze Block and Hainan Island (Table S3); (B) late Mesoproterozoic Kunyang Group, southwest Yangtze Block (our unpublished data); (C) late Mesoproterozoic Liuceng Formation (sixth layer of the Shilu Group) in central Hainan Island (Yao et al., 2017); Table S1: Zircon U-Pb analytical results; Table S2: In-situ zircon Lu-Hf analytical results; Table S3: Sources for data compiled in Figure S1.

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Neoproterozoic–Early Paleozoic Tectonic Evolution of the South China Craton: New Insights from the Polyphase Deformation in the Southwestern Jiangnan Orogen

Acta Geologica Sinica - English Edition ◽

10.1111/1755-6724.13672 ◽

2018 ◽

Vol 92 (5) ◽

pp. 1700-1727 ◽

Cited By ~ 1

Author(s):

Zhongbao ZHAO ◽

Zhiqin XU ◽

Xuxuan MA ◽

Fenghua LIANG ◽

Peng GUO

Keyword(s):

South China ◽

Tectonic Evolution ◽

Early Paleozoic ◽

The South ◽

Polyphase Deformation ◽

South China Craton

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Supplemental Material: Internal versus external locations of the South China Craton within Rodinia during the Cryogenian: Provenance history of the Nanhua Basin

10.1130/gsab.s.12501830 ◽

2020 ◽

Author(s):

Guangyou Zhu ◽

Huichuan Liu

Keyword(s):

South China ◽

Hainan Island ◽

Yangtze Block ◽

The South ◽

Analytical Results ◽

History Of ◽

South China Craton

Text S1: Abbreviations and reference sources of Figure 15; Figure S1: Paleogeographic environments of the western Nanhua Basin (after Jiang et al., 2011 and Bao et al., 2018); Figure S2: (A) Compiled Mesoproterozoic magmatic age data from both Yangtze Block and Hainan Island (Table S3); (B) late Mesoproterozoic Kunyang Group, southwest Yangtze Block (our unpublished data); (C) late Mesoproterozoic Liuceng Formation (sixth layer of the Shilu Group) in central Hainan Island (Yao et al., 2017); Table S1: Zircon U-Pb analytical results; Table S2: In-situ zircon Lu-Hf analytical results; Table S3: Sources for data compiled in Figure S1.

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Precambrian Basement and Late Paleoproterozoic to Mesoproterozoic Tectonic Evolution of the SW Yangtze Block, South China: Constraints from Zircon U–Pb Dating and Hf Isotopes

Minerals ◽

10.3390/min8080333 ◽

2018 ◽

Vol 8 (8) ◽

pp. 333 ◽

Cited By ~ 5

Author(s):

Wei Liu ◽

Xiaoyong Yang ◽

Shengyuan Shu ◽

Lei Liu ◽

Sihua Yuan

Keyword(s):

South China ◽

Tectonic Evolution ◽

Detrital Zircons ◽

Geochemical Data ◽

Precambrian Basement ◽

Yangtze Block ◽

Two Stage ◽

Clastic Rocks ◽

Columbia Supercontinent ◽

Isotopic Analyses

Zircon U–Pb dating and Hf isotopic analyses are performed on clastic rocks, sedimentary tuff of the Dongchuan Group (DCG), and a diabase, which is an intrusive body from the base of DCG in the SW Yangtze Block. The results provide new constraints on the Precambrian basement and the Late Paleoproterozoic to Mesoproterozoic tectonic evolution of the SW Yangtze Block, South China. DCG has been divided into four formations from the bottom to the top: Yinmin, Luoxue, Heishan, and Qinglongshan. The Yinmin Formation, which represents the oldest rock unit of DCG, was intruded by a diabase dyke. The oldest zircon age of the clastic rocks from the Yinmin Formation is 3654 Ma, with εHf(t) of −3.1 and a two-stage modeled age of 4081 Ma. Another zircon exhibits an age of 2406 Ma, with εHf(t) of −20.1 and a two-stage modeled age of 4152 Ma. These data provide indirect evidence for the residues of the Hadean crustal nuclei in the Yangtze Block. In combination with the published data, the ages of detrital zircons from the Yinmin Formation yielded three peak ages: 1.84, 2.30 and 2.71 Ga. The peaks of 1.84 and 2.71 Ga are global in distribution, and they are best correlated to the collisional accretion of cratons in North America. Moreover, the peak of 1.84 Ga coincides with the convergence of the global Columbia supercontinent. The youngest age of the detrital zircon from the Yinmin Formation was 1710 Ma; the age of the intrusive diabase was 1689 ± 34 Ma, whereas the weighted average age of the sedimentary tuff from the Heishan Formation was 1414 ± 25 Ma. It was presumed that the depositional age for DCG was 1.71–1.41 Ga, which was in accordance with the timing of the breakup of the Columbia supercontinent. At ~1.7 Ga, the geochemical data of the diabase were characterized by E-MORB and the region developed the same period A-type granites. Thus, 1.7 Ga should represent the time of the initial breakup of the Yangtze Block. Furthermore, the Yangtze Block continues to stretch and breakup until ~1.4 Ga, which is characterized by the emergence of oceanic island, deep-sea siliceous rock and flysch, representing the final breakup. In brief, the tectonic evolution of the Yangtze Block during the Late Paleoproterozoic to Mesoproterozoic coincided with the events caused by the convergence and breakup of the Columbia supercontinent, because of which, the Yangtze Block experienced extensive magmatic activity and sedimentary basin development during this period.

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Detrital zircon geochronology of pre-Cretaceous strata: tectonic implications for the Jiangnan Orogen, South China

Geological Magazine ◽

10.1017/s0016756813001003 ◽

2014 ◽

Vol 151 (6) ◽

pp. 975-995 ◽

Cited By ~ 22

Author(s):

JINBAO SU ◽

SHUWEN DONG ◽

YUEQIAO ZHANG ◽

YONG LI ◽

XUANHUA CHEN ◽

...

Keyword(s):

South China ◽

North China ◽

Seismic Profile ◽

Upper Jurassic ◽

Detrital Zircons ◽

South China Block ◽

Yangtze Block ◽

The South ◽

Provenance Data ◽

Cathaysia Block

AbstractFifteen sandstone samples taken from pre-Cretaceous strata of the Yangtze Block are analysed to constrain the evolution of the South China Block, especially the assembly between the Yangtze and Cathaysia blocks. The results show that the maximum depositional age of the Neoproterozoic Lengjiaxi Group adjacent to the Cathaysia Block isc. 830 Ma, differing from that of the Kunyang and Dahongshan groups (> 960 Ma) on the southwestern margin of the Yangtze Block. The detrital zircons from Palaeozoic samples from the Yangtze Block have similar age populations to those in the Cathaysia Block, and they may originate from the Cathaysia Block according to palaeogeographic, palaeocurrent and former research data. The detrital zircons of Middle–Upper Jurassic sandstones in the southwestern and central Yangtze Block yield dominant age populations at 2.0–1.7 Ga and subordinate groups of 2.6–2.4 Ga, 0.8–0.7 Ga and 0.6–0.4 Ga. The Upper Triassic strata may be derived from the southern Yangtze and North China blocks due to the collisions between the Indosina, South China and North China blocks, whereas the Jurassic sediments may be partly derived from uplift and erosion of the Jiangnan Orogen due to an intracontinental orogeny induced by Pacific subduction towards the Eurasia Plate. The detrital age spectra and provenance data for basement in the South China Block are analysed and compared with each other. The South China Block has affinity with Australia not only in the Columbia supercontinent but also in the Rodinia supercontinent. We infer the existence of an ancient orogen under the western Jiangnan Orogen, which may have occurred during the Columbia age, earlier than the Sibao orogeny. This is supported by seismic profile proof from the SinoProbe.

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