Article
Geosciences, Multidisciplinary
Anfisa V. Skoblenko, Kirill E. Degtyarev, Nadezhda A. Kanygina, Andrey A. Tretyakov, Sergey Yu Skuzovatov, Kwan-Nang Pang, Hao-Yang Lee
Summary: The Precambrian metamagmatic complexes in the Zhingeldy and Kendyktas blocks of the Zheltau and ChuKendyktas terranes are composed of predominantly Neoproterozoic orthogneisses and subordinate metamorphic rocks. The presence of Precambrian metavolcanic rocks and metasedimentary complexes in the region further indicate the evolution and composition of the studied terranes. The findings also help with the correlation of metamorphic complexes in the SW part of the Central Asian Orogenic Belt.
Article
Geochemistry & Geophysics
Anfisa V. Skoblenko (Pilitsyna), Nadezhda A. Kanygina, Andrey A. Tretyakov, Kirill E. Degtyarev, Truong Tai Nguyen, Kwan-Nang Pang, Victor S. Sheshukov, Kseniya G. Erofeeva
Summary: The metamorphic crustal formations of the Aktyuz block in the Central Asian Orogenic Belt include orthogneisses, gneissic granites, and paragneisses with schists. These rocks experienced high-pressure metamorphism and melting under eclogite facies conditions. The detrital zircons from the metasedimentary formations suggest the presence of Precambrian basement and later subduction processes in the Late Neoproterozoic and Early Palaeozoic.
JOURNAL OF GEODYNAMICS
(2023)
Article
Geochemistry & Geophysics
Da-Di Cao, Yi-Cun Wang, Lu Yin, Bei Xu
Summary: The Xilingol complex in the eastern segment of the Central Asian Orogenic Belt is a significant metamorphic terrane, and studying it provides important insights into the orogenic process and closure of the Paleo-Asian Ocean. The petrological and geochronological analysis revealed that the metamorphic grade of the Xilingol complex decreases gradually from south to north. The south segment experienced high amphibolite facies metamorphism, followed by nearly isobaric cooling, while the north segment underwent low amphibolite facies metamorphism. The age of metamorphic zircons in the north segment is 284.8 +/- 1.9 Ma, indicating the diachronism of Late Paleozoic Buchan-type metamorphism, while the metamorphic zircons in the south segment show discrete metamorphic events.
Article
Geochemistry & Geophysics
Jesse Ray Reimink, Joshua H. F. L. Davies, Alessandro Ielpi
Summary: This passage emphasizes the importance of determining when continental masses emerged above the global ocean in understanding secular changes in crustal and Earth-surface processes. By analyzing the global detrital-zircon record, the study provides a new chronometer for tracking the emergence of continental crust throughout Earth's history.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geochemistry & Geophysics
Xin-Shui Wang, Reiner Klemd, Ji-Lei Li, Jun Gao, Tuo Jiang, Ke-Qing Zong, Sheng-Chao Xue
Summary: The Wuwamen accretionary complex in the Chinese South Tianshan provides important insights into the architecture and evolution of the Central Asian Orogenic Belt. Geochemical and age data indicate diverse origins for the exotic blocks within the complex. The accretionary processes in the complex were active from the early Ordovician to the late Carboniferous. These findings underscore the significant control of long-lasting accretionary processes and terminal collision on the southwestern CAOB.
Article
Geosciences, Multidisciplinary
Chengsen Lu, Jiahui Qian, Changqing Yin, Jian Zhang, Peng Gao, Minjie Guo
Summary: The Trans-North China Orogen in the North China Craton is a typical Paleoproterozoic continental collisional orogen. The Luliang Complex within this orogen has experienced medium-pressure facies series metamorphism, and the metamorphic pattern is characterized by a fan shape. The orogenic evolution in the North China Craton is a protracted process.
EARTH-SCIENCE REVIEWS
(2023)
Article
Geology
Johann Tuduri, Olivier Pourret, Eric Gloaguen, Philippe Lach, Emilie Janots, Sebastien Colin, Jerome Gouin, Matthieu Chevillard, Laurent Bailly
Summary: This study investigates the distribution and formation of nodular grey monazite in the black shales of central Brittany, France. The results reveal the controlling factors and conditions for the formation of monazite, and provide important insights into the geological evolution of the studied area.
ORE GEOLOGY REVIEWS
(2023)
Article
Geosciences, Multidisciplinary
Xingtao Kuang, Xi Xu, Hongwei Duan, Baobao Cao, Fangxin Ning, Mengchu Xiao, Song Han, Daoqing Zhou, Baodi Wang
Summary: The Beidashan-Langshan arcuate tectonic belt in the Alxa tectonic belt (ATB) has a significant impact on the closure of the Paleo-Asian Ocean, the formation of the Central Asian Orogenic Belt (CAOB), and the growth of continental crust. New gravity and magnetic surveys reveal a high-amplitude magnetic anomaly zone distributed across the Quagan Qulu ophiolite belt in the ATB. This magnetic anomaly zone may have originated from a crustal mafic pluton derived from the Late Paleozoic-Triassic Paleo-Asian Ocean. The irregular continental margins, such as the Beidashan-Langshan arcuate tectonic belt, can contribute to the lateral growth of continental crust and serve as an important means of continental accretion in the CAOB.
Article
Geochemistry & Geophysics
Ralf Halama, Gray E. Bebout, Fernando Bea
Summary: The passage discusses the distribution and storage of nitrogen in deep crustal rocks in the Ivrea Zone of the Southern Alps, highlighting changes in nitrogen concentrations and isotopic compositions with increasing metamorphic grade. It reveals that nitrogen is redistributed among silicate phases during devolatilization and melting, showing a strong affinity for certain potassic minerals.
Article
Geosciences, Multidisciplinary
Jinrui Zhang, Shuang Tang, Chunjing Wei, Wenliang Xu, Hang Chu, Ling Jiang
Summary: This study presents systematic data on the metamorphic evolution of the Barrovian metamorphic series, providing insights into its tectonic significance. The P-T path of this series indicates a crustal over-thickening event, followed by prograde metamorphism, decompression, and cooling. The ages of detrital zircons in the mica schist samples suggest that the North China Craton was the source, and the metamorphic age of the sillimanite zone is consistent with the timing of the Devonian orogeny.
JOURNAL OF ASIAN EARTH SCIENCES
(2023)
Article
Geology
Xianfeng Zha, Yunpeng Dong, Dengfeng He, Meng Li, Xiaofeng Gao, Xiaoming Liu, Chaobin Hu, Lili Xu
Summary: The Qimantagh back arc basin underwent complex tectonic evolution processes, including opening, subduction, and closure. The results of this study indicate that the closure of the back arc basin led to a crustal thickening event around 420-410 million years ago.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Geosciences, Multidisciplinary
Jolanta Burda, Urs Kloetzli, Jaroslaw Majka, David Chew, Qiu-Li Li, Yu Liu, Aleksandra Gaweda, Michael Wiedenbeck
Summary: Zircon petrochronology from the Western Tatra Mountains reveals a complex rock evolution with vestiges of independent oceanic domains. The study contributes towards understanding major tectonothermal events that shaped the eastern margin of Gondwana in the Early Palaeozoic, and its subsequent Variscan and later evolution. The rocks record two completely independent oceanic domains preserved within the Central Western Carpathians.
Article
Geochemistry & Geophysics
Jaroslaw Majka, Karolina Kosminska, Jakub Bazarnik, William C. McClelland
Summary: The Thores Suite in the Pearya Terrane of Arctic Canada was formed in an island arc setting during the Early Ordovician period. The presence of xenocrystic zircon with Precambrian ages, typical of Laurentia, suggests a complex geological history for this region. The geochronological dataset reveals insights into the formation of the Thores Suite and its connection to other tectonic events in the Caledonides of northern Scandinavia and Svalbard.
Article
Geosciences, Multidisciplinary
Xin Dong, Zeming Zhang, Zuolin Tian
Summary: The study on orthogneisses in the Milin area of the southeastern Lhasa terrane provides insights into the local protolith crystalline ages and their relation to the Neoproterozoic-Paleozoic strata in the Lhasa terrane. Geochemical data suggests the Mesoproterozoic rocks may have originated from partial melting of Paleoproterozoic crustal materials, representing the Precambrian metamorphic basement of the Lhasa terrane.
PRECAMBRIAN RESEARCH
(2022)
Letter
Geosciences, Multidisciplinary
Shitao Zhang, Qiang Ma, Huayong Chen, Xiaoping Long, Gaobin Chu, Jiamin Cheng, Xiaoping Xia, Rucao Li
Summary: This study presents new in situ U-Pb and Hf-O isotopes data for xenocrystic zircons discovered from Late Mesozoic ultrapotassic to K-rich lamprophyres in the eastern Yangtze Craton, providing important insights into the older age of the deep continental crust compared to surface exposures and the widespread distribution of Archean and Paleoproterozoic crustal materials in the region. The results of Hf-O isotopes of the studied xenocrystic zircons record significant crust growth and reworking in the eastern Yangtze Craton, highlighting the importance of lamprophyres and their xenocrysts as proxy archives of the history of deep continental crust in the region.
PRECAMBRIAN RESEARCH
(2021)