Article
Geochemistry & Geophysics
R. Tamblyn, D. Brown, M. Hand, L. Morrissey, C. Clark, R. Anczkiewicz
Summary: The ca. 2 Ga retrogressed eclogites in the Usagaran Belt in central Tanzania are among the oldest documented eclogites in the world. They provide insights into the thermal conditions of early subduction on Earth and suggest the possible existence of a large subduction system on the margin of west Africa from ca. 2.1-1.9 Ga. This data highlights the operation of modern style subduction on significant geographic and temporal scales during this time period.
Article
Geosciences, Multidisciplinary
Gang Tian, Minghui Yang, Lijun Song, Huichong Jia, Huichuan Liu, Shaohua Zhang, Wei Zhang, Zhou Xing, Jie Chen, Donglai Bai, Jingying Li
Summary: Research reveals that the Precambrian tectonic evolution in the western North China Craton (NCC) and the tectonic division are poorly understood due to limited exposure beneath the Ordos Basin. By analyzing orthogneiss samples from the North Ordos Basin, it is found that the formation of various gneiss types occurred at around 2.51-2.46 Ga, indicating a transition from a compressional regime to an extensional regime. These gneisses originated from different geological processes, such as partial melting of mafic island-arc crust and mantle metasomatism by subduction fluids and melts. The findings suggest the involvement of the North Ordos Basin in the collision event between the Yinshan Block and Ordos Block.
PRECAMBRIAN RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Jingyu Wang, Xiaoping Long, Caiyun Lan, Bin Wu, Rui Zuo
Summary: This study investigates the magmatic activity during the early Paleoproterozoic era in the southern North China Craton (NCC) and identifies ca. 2.3 Ga mafic magmatic records. The rocks exhibit geochemical features of island arc magmas and likely originated from partial melting of a garnet-spinel lherzolite, undergoing a process of hydrous fractionation. The findings suggest that continental tectonic activity continued during the early Paleoproterozoic, contrary to the notion of a global tectonic lull.
PRECAMBRIAN RESEARCH
(2022)
Article
Geochemistry & Geophysics
Yang Huang, Lu Wang, Paul T. Robinson, Wenbin Ning, Yating Zhong, Junpeng Wang, Wei Hu, Ali Polat, Timothy Kusky
Summary: This study documented the characteristics of podiform chromitites from the Archean Zunhua ophiolitic melange in the North China Craton, revealing geochemical and age features similar to typical Phanerozoic podiform chromitites.
Article
Geosciences, Multidisciplinary
Yunxiu Li, Cheng Xu, Lifei Zhang, Jindrich Kynicky, Wenlei Song, Yingwei Fei
Summary: The comprehensive study of olivine-bearing garnet pyroxenite xenoliths in Paleoproterozoic carbonatite revealed that they may originate from refractory mantle wedge in a subduction zone, metasomatized by crust-derived melts. The peak pressure-temperature conditions indicate a cold subduction geothermal gradient for these rocks, suggesting that modern-style subduction of lithospheric mantle was initiated at least since 1.8 Ga.
PRECAMBRIAN RESEARCH
(2021)
Article
Geochemistry & Geophysics
Hai-Yan Su, Yang Yang, Cheng-Cheng Wang, Yi-Can Liu, C. Groppo, F. Rolfo
Summary: The Wuhe complex in the North China Craton is composed of alkaline ultrapotassic granitic gneisses, which may have originated from a subduction-related rifting environment. These rocks represent an important crustal growth event and have undergone a long history of evolution.
Article
Geosciences, Multidisciplinary
Shouwen Chen, Jiahao Li, Feng Yuan, Simon M. Jowitt, Longming Li, Yufeng Deng, Hang Liu, Ren Jiang
Summary: This study presents new data on the tectonic evolution of the Yangtze Craton during the late Neoarchean to early Paleoproterozoic. The findings indicate that modern-style subduction occurred within the northeastern Yangtze Craton between 2.5 to 2.47 billion years ago, based on the analysis of orthogneisses from the Feidong Complex. This provides important evidence for understanding the geological history of the region.
PRECAMBRIAN RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Amitava Chatterjee, N. V. Chalapathi Rao, Rohit Pandey, Ashutosh Pandey
Summary: This paper reports the discovery of a kimberlite-borne eclogite xenolith containing ultra-high-pressure minerals in the Kalyandurg kimberlite cluster of India's Eastern Dharwar Craton. Through analysis, the presence of coesite, majoritic garnet, and supersilicic K-rich omphacite was confirmed. The study suggests that the xenolith may have descended to the mantle transition zone before being rapidly uplifted by a pre-Mesoproterozoic mantle plume and subsequently entrained as a xenolith by Mesoproterozoic kimberlite.
GEOLOGICAL MAGAZINE
(2023)
Article
Geosciences, Multidisciplinary
Daniele Regis, Sally Pehrsson, Edith Martel, Eric Thiessen, Tony Peterson, Dawn Kellett
Summary: The text discusses the formation of the Trans-Hudson Orogen (THO) and presents new research findings on the south Rae craton, highlighting evidence of burial and magmatic activity. It proposes an updated model for the evolution of the region and suggests that the Paleoproterozoic THO represents the first record of a major 'modern-style' orogenic plateau collapse in Earth's history.
PRECAMBRIAN RESEARCH
(2021)
Article
Geochemistry & Geophysics
Petra Herms, Peter Raase, Christopher Giehl, Laszlo E. Aradi, Tobias Fusswinkel, Arno Rohrbach, Andreas Moeller
Summary: The investigation of polymineralic melt inclusions preserved in garnet of eclogite-facies metapelites in the Usagaran belt, Tanzania, provides important insights into the process of partial melting and subduction in ancient oceanic crust. The study reveals the presence of a CO2-rich fluid phase, the formation of dolomite-quartz-kyanite inclusions, the precipitation of graphite from the CO2 fluid, and the composition of a homogeneous rhyolitic melt. The results also suggest a rapid uplift of the oceanic crustal rocks.
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY
(2023)
Article
Geosciences, Multidisciplinary
Yanyan Zhou, Qianying Sun, Taiping Zhao, Mingguo Zhai
Summary: The study confirms igneous activity along the southern margin of the North China Craton during the interval of 2.32 to 2.29 Ga, filling in the magmatic gap in the early Paleoproterozoic. The high-K granites display transitional characteristics between S-type and A-I-type granites, with zircons showing low but positively stable delta O-18 values pointing towards an older crustal source. The diversity of rock assemblages and geochemical features suggest a crustal melting linked to a thermal anomaly in an extensional setting.
PRECAMBRIAN RESEARCH
(2021)
Article
Multidisciplinary Sciences
Bo Wan
Summary: Plate tectonics is a fundamental theory in Earth science, and this study proposes that a global subduction network is the essence of plate tectonics. Through comprehensive geological observations, key evidence of large-scale horizontal movement and subduction of an oceanic plate nearly 2 billion years ago in China's North China Craton was found. The study also revealed a geophysical interface preserved by ancient continental convergence. Based on these findings, it is proposed that Earth gave birth to its global plate subduction network 2 billion years ago, leading to the formation of Earth's earliest supercontinent. This knowledge is important for understanding Earth's past and predicting its future.
CHINESE SCIENCE BULLETIN-CHINESE
(2022)
Article
Geochemistry & Geophysics
L. I. Lobkovsky, A. A. Baranov, M. M. Ramazanov, I. S. Vladimirova, Yu. V. Gabsatarov, D. A. Alekseev
Summary: A seismogenic-trigger mechanism is proposed to explain the activation of methane emission and subsequent climate warming in the Arctic and Antarctic regions. This mechanism is associated with deformation tectonic waves caused by strong earthquakes in subduction zones, resulting in the release of methane from hydrate-bearing sedimentary rocks and accelerated climate warming. The process also leads to the destruction of glacier ice and ice shelves in Antarctica. The hypothesis suggests that an increase in strong earthquakes in the South Pacific subduction zones will further exacerbate glacier destruction and climate warming in Antarctica.
IZVESTIYA-PHYSICS OF THE SOLID EARTH
(2023)
Article
Oceanography
L. I. Lobkovsky, A. A. Baranov, I. S. Vladimirova, Y. V. Gabsatarov
Summary: A mechanism involving deformation waves in the lithosphere-asthenosphere system caused by large earthquakes in surrounding subduction zones is proposed as the trigger for the rapid destruction of cover and shelf glaciers in West Antarctica, along with the release of methane and subsequent climate warming. These disturbances transmit over long distances and introduce additional stresses to Antarctica, causing decreased adhesion between glaciers and rocks, accelerated sliding of glaciers, and the development of faults. This process also leads to the release of methane from gas-hydrate-bearing sedimentary layers, contributing to climate warming. This hypothesis suggests that glacier destruction and climate warming in Antarctica will accelerate in the future due to increased large earthquakes in South Pacific subduction zones.
