Provenance of rift sediments in a composite basin–mountain system: constraints from petrography, whole-rock geochemistry, and detrital zircon U–Pb geochronology of the Paleocene Shashi Formation, southwestern Jianghan Basin, central China

AbstractThe Qinling Orogen and the Jiyuan Basin constitute a basin-mountain system during the Early Mesozoic. Therefore, sediments from the Jiyuan Basin can be used to deduce the orogenic process of the Qinling Orogen. This paper attempts to use detrital zircon trace elements with ages ranging from the Late Carboniferous to the Middle Triassic that were obtained from the Jiyuan Basin to discuss the tectonic evolution of Qinling Orogen. On the tectonic setting discriminating diagrams, most grains are concentrated in convergent continental margins/orogenic settings,whereas the remaining samples (268 Ma, 265Ma, 264 Ma and 254Ma) are plotted in anorogenic field. Compared to the Early Paleozoic (400-500Ma) zircons, 306Ma and 281Ma grains represent higher Th/ Nb ratios, which might be related to the Mianlve oceanic crust subduction. The lower Th/Nb ratios containing 268 Ma, 265Ma, 264 Ma and 254Ma grains might indicate lithospheric extension subsequently. The final continent-continent collision between South China and North China blocks took place after the Middle Triassic (242Ma).

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Detrital zircon (U–Th)/He thermochronometry of the Mesozoic Daba Shan Foreland Basin, central China: Evidence for timing of post-orogenic denudation

Tectonophysics ◽

10.1016/j.tecto.2012.08.010 ◽

2012 ◽

Vol 570-571 ◽

pp. 65-77 ◽

Cited By ~ 16

Author(s):

Yuntao Tian ◽

Nansheng Qiu ◽

Barry P. Kohn ◽

Chuanqing Zhu ◽

Shengbiao Hu ◽

...

Keyword(s):

Detrital Zircon ◽

Foreland Basin ◽

Central China

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U–Pb dating on single detrital zircon grains from the Triassic Songpan–Ganze flysch (Central China): provenance and tectonic correlations

Earth and Planetary Science Letters ◽

10.1016/s0012-821x(97)00138-6 ◽

1997 ◽

Vol 152 (1-4) ◽

pp. 217-231 ◽

Cited By ~ 197

Author(s):

O. Bruguier ◽

J.R. Lancelot ◽

J. Malavieille

Keyword(s):

Detrital Zircon ◽

Central China

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Geochemistry of the Paleocene Clastic Rocks From the Southwestern Jianghan Basin, Central China Reveal Their Provenance, Tectonic Setting, and Palaeoenvironment

10.21203/rs.3.rs-956386/v1 ◽

2021 ◽

Author(s):

Kai Yan ◽

Chun-lian Wang ◽

Jiu-yi Wang ◽

Xiao-can Yu ◽

Xiao-hua Teng ◽

...

Keyword(s):

Tectonic Setting ◽

Active Continental Margin ◽

Source Area ◽

Source Rocks ◽

Central China ◽

Clastic Rocks ◽

Ree Distribution ◽

C Value ◽

Tectonic Settings ◽

Jianghan Basin

Abstract This paper intends to learn about the provenance, tectonic setting and paleoenvironment of the Paleocene Shashi Formation in the southern Jianghan Basin by the bulk-rock geochemistry. The K2O/Al2O3 and SiO2/Al2O3 ratios indicate that the major proportion of samples are litharenite. The chondrite-normalized REE distribution pattern of the Shashi Formation’s mudstones are characterized by enriched LREE and flat HREE similar to those of UC with negative Eu anomalies. Combined with the geochemical element ratio discriminant diagram, such as Al2O3-TiO2, Zr-TiO2, La/Sc-Co/Th, and Hf-La/Th, so on, these samples were sourced from mixed felsic/basic rock. Moreover, the discriminant diagrams of K2O/Na2O-SiO2/Al2O3, La-Th-Sc, and Th-Co-Zr/10 suggest that the samples were formed under the tectonic settings of active continental margin and continental island arc. The values of CIA, CIW, PIA, ICV, Zr/Sc-Th/Sc, and ternary diagrams of A-(CN)-K and Al2O3-Zr-TiO2 indicate that weathering in the source area was weak and source rocks have not been reformed by depositional recirculation and hydraulic sorting. And the palaeoenvironmental indicators of C-value, Ni/Co, V/Cr, V/(V+Ni) and Sr/Cu, Ga/Rb indicate that the climate was cool and arid during the evaporite deposition period in the southern Jianghan Basin, and the water was in the condition of oxidation.

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