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This paper presents a systematic study of late Cretaceous to early Tertiary magmatism in the eastern Gangdese batholith (Lhasa–Nyingchi segment), the southern Lhasa terrane, southern Tibet. Based on zircon U–Pb age, rock association and geochemistry, the magmatism can be divided into three stages: 95–86Ma (stage-1), 85–73Ma (stage-2) and 68–60Ma (stage-3), with a short magmatic quiescence or gap of...
The Himalayan leucogranites are critical for understanding the geodynamic process of Himalayan orogenesis. In this article, we present petrological, geochronological and geochemical results of the Ramba leucogranites that crop out in the center of the Ramba dome within the Tethyan Himalaya. U–(Th)–Pb dating of zircon, monazite and xenotime revealed three episodes of leucogranitic magmatism in the...
The Purang ophiolite tectonically was thrust over an Upper Cretaceous mélange south of the Yarlung-Zangbo Suture Zone (YZSZ) in SW Tibet. It comprises a large ultramafic massif of ~800km 2 , but plutonic and volcanic sections are notably absent. The Purang peridotite massif is dominated by harzburgites with minor clinopyroxene-poor lherzolites, which are occasionally intruded by gabbronoritic...
Petrology, geochemistry and ReOs isotopes of peridotite xenoliths from Maguan (Yunnan Province) are reported in this paper with the aims of constraining the age and evolution of the lithospheric mantle beneath the western margin of the Cathyasia block. The Maguan mantle xenoliths contain predominantly fertile lherzolites with whole-rock Al 2 O 3 contents of 2.42–4.99wt.%, and subordinate...
South China is famous for its polymetallic deposits, with more than 50% of the world's W and Sb reserves and 20% of the Sn reserves, as well as abundant Cu–Mo–Pb–Zn–Au–Ag, Ta, Nb, HREE and U. This special issue reports recent progress on the tectonic evolution, magmatism and ore deposits of South China, which leads to a more comprehensive understanding of the Mesozoic large scale magmatism and mineralization...
The Xinchang mantle xenoliths, including garnet lherzolites, spinel lherzolites and harzburgites, have been studied for the nature and age of the lithospheric mantle beneath southeastern (SE) China. The spinel harzburgites have refractory compositions, with 0.95–1.73wt.% Al 2 O 3 , 0.65–1.47wt.% CaO, 0.03–0.16wt.% TiO 2 and 2134–2422ppm Ni. The lherzolites (both spinel- and...
Mesozoic magmatism is extensively developed in eastern China along the eastern Asian continental margin, but the geochronological framework is not well understood for each area. In this study, seventy-eight samples were collected from the Mesozoic igneous rocks in south Anhui Province, east-central China, in order to precisely constrain their formation ages and contributions to crustal growth. Zircon...
The North China Craton (NCC) is the typical example of destruction of an ancient craton. However, the destruction mechanism and geodynamic controlling factors still remain enigmatic due to controversy on the timing of destruction, which is the key to understanding the destruction processes. Based on temporal and spatial distributions of the igneous rocks, and their sources and tectonic settings, it...
The Phalaborwa carbonatite Complex, situated in the northeastern part of South Africa, is characterized by copper and zirconium mineralization, and is composed principally of pyroxenites, phoscorite and carbonatite (banded and transgressive). The complex is transected by mafic dykes, and is geographically associated with a satellite syenite and minor granite intrusions. Zircon and baddeleyite U–Pb...
Potassic basaltic lavas erupted during the Cenzoic are widespread in Wudalianchi, Erkeshan and Keluo (WEK) areas, northeast China, and contain abundant mantle xenoliths. Mantle xenoliths in this study are selected from the Keluo potassic lavas, and mainly comprise spinel lherzolites and harzburgites with minor dunites and wehrlites. Modal metasomatism is evident in some Keluo xenoliths from the presence...
Zircon Hf and whole-rock Sr–Nd isotopic compositions were determined for postcollisional mafic–ultramafic and felsic intrusive rocks in the Dabie orogen. The results provide not only insights into the character of their source rocks and the nature of crust–mantle interaction, but also constraints on the crustal architecture of continental collision orogen. SHRIMP zircon U–Pb dating gave concordant...
Kimberlite, a deep-sourced ultramafic potassic rock, carries not only diamond, but also invaluable mantle xenoliths and/or xenocrysts, which are important for tracking the evolution of subcontinental lithospheric mantle (SCLM). However, it is challenging to accurately determine the emplacement age of kimberlite and its compositions of primary magma because of modifications by crustal and/or mantle...
In situ U–Pb age and Sr-, Nd-, Hf- and O- isotope analysis of accessory minerals (zircon, apatite and titanite) have been obtained for mafic microgranular enclaves and their host granites from the Early Cretaceous Fangshan pluton in the North China Craton, in order to constrain their sources and petrogenesis. The Fangshan pluton is composed of quartz monzodiorite at the margins, and granodiorite,...
The middle-lower reaches of the Yangtze River is one of the most important metallogenic belts in China, hosting numerous Cu–Fe–Au–Mo deposits. Previous chronological and geochemical investigations mostly focused on the magmatic rocks and associated deposits in the lower reaches of the river, but the timing and genesis of the Cu–Au–(Mo) mineralized porphyries in the middle reaches are yet to be well...
Determination of the emplacement ages and initial isotopic composition of kimberlite by conventional isotopic methods using bulk rock samples is unreliable as these rocks usually contain diverse clasts of crustal- and mantle-derived materials and can be subject to post-intrusion sub-aerial alteration. In this study, 8 samples from 5 kimberlites in southern Africa and twelve samples from 7 kimberlites...
Plagioclase crystals with an anorthite content up to An 99 have been discovered in mantle peridotites from the Yungbwa ophiolite, which crops out along the Indus–Yarlung Zangbo Suture, southwestern Tibetan Plateau. Amphiboles of pargasitic composition also occur in these plagioclase peridotites. Microtextures support the view that both plagioclase and amphibole were formed metasomatically...
TTG rocks are commonly assumed to form by partial melting of oceanic crust during slab subduction or anatexis of thickened lower crust. The two models are tested by an integrated study of geochronology and geochemistry for a composite batholith of Neoproterozoic granitoids (mainly TTG-like) from the Yangtze Gorge in South China. Zircon U–Pb dating indicates that all granitoids crystallized in a period...
Different types of metamorphic zircon are recognized by a combined study of petrography, U–Th–Pb and Lu–Hf elements and isotopes in zircons from eclogite-facies metagranites in the Dabie orogen. The results provide petrological distinction between metamorphic growth and recrystallization with respect to protolith inheritance, fluid and melt effects. Zircon U–Pb dating for the metagranites yields two...
Multiple subduction events occurred preceding the collision of Greater India with the Karakoram terrane that consumed the Neotethyan Ocean between Early Cretaceous and Eocene time. Zircon U–Pb dating and Hf isotope analyses of granitic rocks collected from the Karakoram terrane and Ladakh batholith have been conducted to constrain these geological processes. Undeformed Ladakh batholith granodiorite...
The Great Xing'an Range in northeastern China is characterized by large-scale Mesozoic magmatism, and forms a key part of the NE-trending Mesozoic magmatic belt in East China. However, only limited precise age data for the volcanic rocks in this belt were previously available, which significantly hampers understanding of the petrogenesis and geodynamic setting of these rocks. Systematic dating of...
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