Mineralization age and sources of ore‐forming material of the Nanmushu Zn‐Pb deposit in the Micangshan Tectonic Belt at the northern margin of the Yangtze Craton, China: Constraints from Rb‐Sr dating and Sr‐Pb isotopes

2020 ◽  
Vol 70 (3) ◽  
pp. 273-295
Author(s):  
Zhijiao Song ◽  
Cuihua Chen ◽  
Yulong Yang ◽  
Yan Zhang ◽  
Li Yin ◽  
...  
Keyword(s):  
Pb Isotopes ◽  
Yangtze Craton ◽  
Northern Margin ◽  
Mineralization Age ◽  
Tectonic Belt

Petrogenesis and tectonic significance of the middle Neoproterozoic highly fractionated A-type granite in the South Qinling block

2021 ◽  
pp. 1-20
Author(s):  
Xiao-Fei Qiu ◽  
Qiong Xu ◽  
Tuo Jiang ◽  
Shan-Song Lu ◽  
Long Zhao
Keyword(s):  
Tectonic Setting ◽  
Eastern China ◽  
Continental Rift ◽  
The South ◽  
Yangtze Craton ◽  
Dabie Orogen ◽  
Northern Margin ◽  
South Qinling ◽  
Type Granite ◽  
High Alkali

Abstract The South Qinling block, a segment of the Yangtze craton involved in the Qinling–Dabie orogen, is critical for understanding the tectonic evolution of eastern China. However, the tectonic setting of the South Qinling block and the northern margin of the Yangtze block during middle Neoproterozoic time has long been the subject of debate, with two distinctly different models (continental rift or volcanic arc) proposed. Here, a comprehensive study of zircon U–Pb geochronology and geochemistry has been carried out on the Chengwan granitic pluton from the Suizao terrane in the South Qinling block. The granites are monzogranite and syenogranite in lithology, and are mainly composed of potash feldspar, quartz, plagioclase and biotite. This suite has long been regarded as a Palaeozoic magmatic pluton, but zircon U–Pb ages of 809 ± 9 Ma and 816 ± 4 Ma are obtained in this study. The granites are metaluminous to strongly peraluminous with high alkali contents, and exhibit highly fractionated features, including high SiO2, low Zr/Hf ratios, rare earth element tetrad effects and enrichment of K and Rb. They show Hf–Nd isotopic decoupling, which may be genetically related to their petrogenetic process. Based on the geochemical features and the positive εHf(t) values of the zircons, it is indicated that the granites may have been derived from partial melting of juvenile tonalitic rocks by biotite breakdown under fluid-absent conditions. The Chengwan granite geochemically belongs to the A2-subtype granites, suggesting that it might have formed in a post-orogenic tectonic setting. The highly fractionated A-type granite in this study may represent extensional collapse shortly after the collisional events in the South Qinling block, and thus indicate a tectonic regime switch, from compression to extension, as early as middle Neoproterozoic time. Integrating our new data with documented magmatic, metamorphic and sedimentary events during middle Neoproterozoic time in the region may support a continental rift model, and argues against arc models.

scholarly journals Re-Discussion on the Metallogenic Age of the Hadamengou Gold Deposit in Inner Mongolia, China

2016 ◽  
Vol 5 (2) ◽  
pp. 85
Author(s):  
Yu Zhang ◽  
Yangyang Chen
Keyword(s):  
Gold Deposit ◽  
Inner Mongolia ◽  
North China ◽  
Northern Margin ◽  
The North ◽  
Geological Evolution ◽  
Western Segment ◽  
Mineralization Age ◽  
Extensive Collection ◽  
Metallogenic Age

The Hadamengou gold deposit is located in the western segment of the northern margin of the North China Craton (NCC). The mineralization age of the Hadamengou gold deposit is a matter of controversy. Based on the extensive collection the results of previous research, we infer that the Hadamengou gold deposit is exposed to prolonged geological evolution. It was formed as early as the Middle Hercynian orogen. The metallization mainly took place in the Early Indosinian epoch.

SHRIMP Age and Geochemistry of the Bikou Volcanic Terrane: Implications for Neoproterozoic Tectonics on the Northern Margin of the Yangtze Craton

2010 ◽  
Vol 77 (4) ◽  
pp. 479-490 ◽  
Author(s):  
YAN Quanren ◽  
WANG Zongqi ◽  
A. D. HANSON ◽  
P. A. DRUSCHKE ◽  
YAN Zhen ◽  
...  
Keyword(s):  
Yangtze Craton ◽  
Northern Margin

Active Faulting of Landforms along the Tuosuhu-Maoniushan Fault and Its Seismotectonic Implications in Eastern Qaidam Basin, China

2022 ◽  
Author(s):  
Guihua Chen ◽  
Xun Zeng ◽  
Zhongwu Li ◽  
Xiwei Xu
Keyword(s):  
Late Quaternary ◽  
Qaidam Basin ◽  
Slip Rate ◽  
Northern Margin ◽  
The North ◽  
Fold And Thrust Belt ◽  
Field Investigations ◽  
High Resolution Satellite Images ◽  
Geomorphic Features ◽  
Tectonic Belt

Abstract The fold-and-thrust belt along the northern margin of the Qaidam basin is a typical active tectonic belt located in the northeast Tibetan Plateau. This belt is at a high risk of strong earthquakes with magnitudes larger than 6, as shown by multiple recorded events during 1962–2009. The lack of detailed late Quaternary surficial faulting data and systematic seismotectonic studies has posed difficulties in properly assessing the seismic risks and understanding the ongoing geodynamics in this region. In this study, we mapped the geomorphic features and fault traces from high-resolution satellite images and field investigations of the Tuosuhu-Maoniushan fault (TMF). Field photogrammetry was conducted to obtain deformation measurements using a DJI M300 real-time kinematic (RTK) drone. The TMF displaces the Holocene and late Pleistocene alluvial terraces in the eastern Qaidam basin. This fault dips to the south in the west and central segments (as a boundary of the Denan depression) and to the north in the eastern segment along the piedmont of the Maoniushan Mountains. The vertical slip rate is estimated to be 0.37 ± 0.08 mm/yr, which is similar to that of the active southern Zongwulongshan fault. By integrating our investigations with the previously published studies on deep structures and Cenozoic geology of the region, we propose a deep-seated thrust model for the seismotectonics of the northern margin of the Qaidam basin. The Aimunike, Tuosuhu-Maoniushan, southern Zongwulongshan, and Zongwulong faults, along with many folds, form an active compressional zone. The complex across-strike structures and along-strike segmentation could facilitate the release of strain through earthquakes of magnitude 6–7 in this broad seismotectonics belt, rather than through strong surface-rupturing events resulting from a single mature large fault.

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