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Acta Geologica Sinica(English Edition) 2024年第3期98卷 641-656页

作者： WANG Qiuyu CHEN Shouming ZHANG Hongrui LI Saisai SinoProbe Laboratory Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Guangxi Key Laboratory of Hidden Metallic Ore Deposit Exploration GuilinGuangxi 541004China

High-silica granitoids record the formation and evolution of the continental crust.A new intrusive complex has been recognized among silicic volcanic rocks of the Weixi arc,Southwest China.The intrusions consist of granites,granitic porphyries,and granodiorites.Zircon U-Pb age data indicate that the Weixi granitoids formed at 248-240 Ma and were coeval with silicic volcanic rocks of the Weixi arc.The Weixi granitoids are enriched in Rb,Th,and U,depleted in Ba,Sr,Nb,Ta,and Ti,and have high light/heavy rare earth element ratios and slightly negative Eu anomalies.The Weixi granitoids have negative ε_(Nd)(t)values(-9.8 to-7.8)and negative zircon ε_(Hf)(t)values(-12.02 to-5.11).The geochemical and isotopic features suggest the Weixi granitoids were derived by partial melting of ancient crustal material.The Weixi granitoids and silicic volcanic rocks were derived from the same magma by crystal accumulation and melt extraction,respectively,and they record the formation of a continental arc in the central Sanjiang orogenic belt.

关键词： granitoids geochemistry crystal accumulation continental crust Sanjiang orogen

Trace element tectonic discrimination of granitoids:inspiration from big data analytics

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Big Earth Data 2023年第4期7卷 1094-1119页

作者： Wan-Feng Chen Qi Zhang Jing Yang Er-Teng Wang Gao-Rui Song Shou-Tao Jiao Jie Yuan College of Geography and Tourism Hunan University of Arts and ScienceChangdeChina blnstitute of Geology and Geophysics Chinese Academy of SciencesBeijingChina School of Earth Sciences Lanzhou UniversityKey Laboratory of Mineral Resources in Western ChinaLanzhouGansuChina Development Research Center China Geological SurveyBeijingChina Technology Innovation Center of Geological Information MNRBeijingChina School of Resources and Environment Xingtai UniversityXingtaiHebeiChina

The tectonic environment of granitoids has always been a concern of the academic community.The Nb vs.Y and Rb vs.Nb+Y diagrams have had a substantial impact.The present work uses more than 110,000 granitoid samples(SiO_(2)≥56%)from the globally shared database to discuss the validity and also explain why these diagrams used for discrimination between the different tectonic settings of granitoid rocks.The amount of data from the spreading center is sparse and the data are highly scattered and so,the present study focuses mainly on granites from the ocean islands and convergent margins tectonic environments.On the TAS diagram most of the ocean island data are alkaline series and trachybasalt series,and some are bimodal.In contrast,the granitoids on the convergent margin are mainly sub-alkaline.This work shows that the tectonic discrimination diagrams of granitoids remain valid,and only the boundaries need to be slightly adjusted.

关键词： Spreading center Ocean Island Apenninic-Maghrebides chain tectonic discrimination granitoids convergent margin

Petrology and Geochemical Relationship of Birimian Gabbro-Diorite-Granodiorite Dykes in Basaltic Rocks at Butre Area, SW Ghana

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Journal of Geoscience and Environment Protection 2024年第2期12卷 107-130页

作者： Victor Graham George Mensah Tetteh Department of Geological Engineering University of Mines and Technology Tarkwa Ghana

granitoids at Butre area, south-western part of the Birimian of Ghana are gabbro to granodiorite which intruded comagmatic basalt and andesite of volcanic island arc setting. Differentiation was from probably mantle fractionates on tholeiitic basalt trend through gabbro-diorite and granodiorite. Yet, the diorite intruded into the volcanic rocks prior to plate collision. Plagioclase feldspars of labradorite to andesine compositions (An52 - An48), amphibole and pyroxene are in association with accessory tourmaline, actinolite, apatite and garnet. Relict amphibolite facies metamorphism is preserved in xenoliths in gabbro to diorite which show greenschist facies. Generally, plagioclase is partially altered to fine quartz, sericite and carbonates whereas chlorite and epidote are of amphibole alteration. These alterations are typical of carbonatisation but diorite shows partial carbonate-sericite alteration. Alterations followed granodiorite emplacement. Arsenopyrite and pyrite accompanied emplacement of diorite and granodiorite respectively while amphibolite facies metamorphism introduced magnetite;haematite and pyrrhotite accompanied greenschist facies metamorphism. Earlier opaque minerals possibly were consumed to form later minerals. All the rocks are LREE depleted (La/Sm chondrite normalised ratios of basalt = 0.8 to 2.5;andesite = 2.03;diorite = 1.95 to 3.1;gabbro-diorite = 0.9 to 2.05;granodiorite = 1.66);diorite, basalt and andesite are fairly enriched in HREE. Enrichment of FeOT, MgO, SiO2, CaO and depletion of TiO2, K2O and Zr might be linked with carbonitisation, sericitisation, chloritisation, silicification and sulphidation linked to gold mineralisations in the Birimian of Ghana.

关键词： granitoids Petrography Alteration Metamorphism Geochemistry Butre

Petrogenesis and tectonic implications of Indosinian granitoids from Western Qinling Orogen,China:Products of magma-mixing and fractionation

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Geoscience Frontiers 2020年第4期11卷 1305-1321页

作者： Xiao Xiong Laimin Zhu Guowei Zhang M.Santosh Hang Jiang Jun Zheng Anlin Guo Lele Ding State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing 100083China Department of Earth Sciences University of AdelaideAdelaideSA5005Australia

The Western Qinling Orogen(WQO) is characterized by voluminous distribution of Indosinian granitoids,the formation of which provides an important window to unravel the geochemical and geodynamic evolution and associated metallogeny.Here we investigate a group of intrusions termed "Five Golden Flowers" based on petrological,geochemical,zircon U-Pb geochronological and Lu-Hf isotopic studies on the granitoids and their mafic microgranular enclaves(MMEs).Our results show that these intrusions are genetically divided into two types,namely,magma-mixing and highly fractionated.The Jiaochangba,Lujing,Zhongchuan,and Luchuba granitoids are biotite monzogranites(220±0.8 Ma to 217±2.6 Ma) with abundant coeval MMEs(220±.1 Ma to 217±2.7 Ma).The rocks contain moderate to high SiO2,high MgO,Rb,Sr,Ba,and Th contents,but low TiO2,P2 O5,and Sc values,A/CNK of granitoids were produced by partial melting of latePaleoproterozoic to early-Mesoproterozoic lower crust with the involvement of Neoproterozoic SCLM-derived mafic magmas.The Baijiazhuang pluton is dominantly composed of leucogranite(muscovite granite and twomica monzogranite,216±1.5 Ma) without MMEs.The rocks are peraluminous with high A/CNK(1.06-1.27).Compared with the other four granitoids,the Baijiazhuang leucogranite shows higher SiO2 content,markedly lower concentrations of TiO2,MgO,Al2 O3,CaO,and Fe2 O3T,and lower LREE/HREE and(La/Yb)N values.These leucogranites are also rich in Rb,Th,and U,and display marked depletions in Ba,Sr,Ti,and Eu,indicating that they experienced significant fractionation.Zircon εHf(t) values(-10.2 to-3

关键词： granitoids Western qinling orogen MMEs Magma mixing Fractionation Syn-to post-collisional transition

Zircon Trace Element Constraints on the Evolution of the Paleoproterozoic Birimian granitoids of the West African Craton(Ghana)

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Journal of Earth Science 2018年第1期29卷 43-56页

作者： Patrick Asamoah Sakyi Benxun Su Daniel Kwayisi Chen Chen Yang Bai Melesse Alemayehu Department of Earth Science School of Physical and Mathematical Sciences University of Ghana Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences School of Earth Science University of Chinese Academy of Sciences School of Applied Natural Science Applied Geology Department Adama Science and Technology University

The Paleoproterozoie Birimian granitoids of the West African Craton （WAC） in the northwestern part of Ghana, have been studied for their zircon trace elements concentrations to infer the source characteristics, origin, and magmatic evolution. The zircons in the granitoids have Th/U ratios ranging from 0.03 to 1.55, and display depleted light rare earth elements 0LREE） and enriched heavy rare earth elements （HREE） contents, characterized by pronounced positive to negative anomalies of Eu （Eu/Eu＊=0.14-0.98 and 1.01-6.06, respectively） and Ce （Ce/Ce＊=0.08-0.98 and 1.02-116, respectively）, which may imply that they were derived from both magmatic and hydrothermal sources. The geochemical plots of U/Yb vs. Y and Hf, the positive correlation between Hf and the other high field strength elements 0tFSE） and high rare earth elements （REE） contents, with enrichment in Ce and depletion in Eu, indicate that the granitoids possibly formed from partial melting of the crust. The trace elements characteristics （i.e., wide range of Hf, Ce/Ce＊, Th/U and Zr/Hf values） of the zircons suggest that crystallization of the magma occurred under variable oxidation states, which spanned over a longer period, implying that our data corroborate interpretations from studies of whole-rock geochemistry and geochronology on the granitoids of northwestern Ghana. This further indicates that the evolution of the Birimian granitoids in this part of the WAC occurred earlier than what had been reported in the literature.

关键词： West African Craton granitoids zircon trace elements magmatic evolution hydro-thermal alteration.

Petrogenesis of shoshonitic granitoids,eastern India:Implications for the late Grenvillian post-collisional magmatism

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Geoscience Frontiers 2014年第6期5卷 821-843页

作者： B.Goswami C.Bhattacharyya Department of Geology University of Calcutta35 Ballygunge Circular RoadKolkata 700 019India

Many elongated, lenticular plutons of porphyritic granitoids are distributed mainly near the southern and northern margin of the Chhotanagpur Gneissic Complex （CGC） which belongs to the EW to ENE-WSW tending 1500 km long Proterozoic orogenic belt amalgamat ng the North and South Indian cratonic blocks. The late Grenvillian （1071 ±64 Ma） Raghunathpur porphyritic granitoid gneiss （PGG） batholith comprising alkali feldspar granite, granite, granodiorite, tonalite, quartz syenite and quartz monzonite intruded into the granitoid gneisses of southeastern part of CGC in the Purulia district, West Bengal and is aligned with ENE-WSW trending North Purulia sr^ear zone, Mineral chemistry, geochemistry, physical condition of crystallization and petrogenetic model of Raghunathpur PGG have been discussed for the first time. The petrographic and geochemical features （including major and trace- elements, mineral chemistry and S7Sr/S6Sr ratio） suggest these granitoids to be classified as the shosh- onitic type. Raghunathpur batholith was emplaced at around 800 ~C and at 6 kbar pressure tectonic discrimination diagrams reveal a post-collision tectonic setting while structural studies reveal its emplacement in the extensional fissure of North Purulia shear zone. l＇he Raghunathpur granitoid is compared with some similar granitoids of Europe and China to draw its petrogenetic model. Hybridi- zation of mantle-generated enriched mafic magma and crustal magma at lower crust and later fractional crystallization is proposed for the petrogenesis of this PGG. Mafic magma generated in a post-collisional extension possibly because of delamination of subducting slab. Raghunathpur batholith had emplaced in the CGC during the final amalgamation （~ 1.0 Ga） of the North and South Indian cratonic blocks. Granitoid magma, after its generation at depth, was transported to its present level along megadyke channel, ways within shear zones.

关键词： granitoids Petrology Geochemistry Shoshonitic Post-collisiooal Chhotanagpur Gneissic Complex

Geochemistry and Petrogenesis of the ca. 2.5Ga High-K granitoids in the Southern North China Craton

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Journal of Earth Science 2019年第3期30卷 647-665页

作者： Lei Li Wenjian Zhai State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences Wuhan 430074 China No.1 Geology and Mineral Resources Survey Institute of Henan Geology and Mineral Exploration and Development Bureau Luoyang 471023 China Henan Institute of Geological Survey Zhengzhou 450001 China

Archean high-K granitoids, generally formed after tonalite-trondhjemite-granodiorite (TTGs), are important for understanding crustal reworking of ancient cratons. The Linshan Archean high-K granitoids from the southern Trans-North China Orogen (TNCO) provide a window into the conti-nental crustal evolution of the North China Craton (NCC). They mainly consist of monzogranite and granodiorite which were formed during 2 542-2 503 Ma. The high-K granitoids have high SiO2 (65.86wt.%-78.08wt.%), K2O (3.29 wt.%-7.62wt.%) and low P2O5 (0.01 wt.%-0.27wt.%). They display right inclined REE patterns with negative Eu anomalies (Eu/Eu*=0.20-0.81).Their spider diagram is characterized by enrichment of Rb, K, Th, U and depletion of Nb, Ta, Zr, Ti. The rocks have positive and variable zircon εHf(t)(+2.5 to +6.6) and whole-rock εHf(t)(+0.7 to +4.5) with two-stage model ages (TDM2^Hf=2.87-2.64 Ga;TDM2^Nd=2.77-2.50 Ga) similar to those of the Archean TTG-ty pe rocks, amphibolites and diorites in the area. These evidences suggest that the high-K granitoids were produced by partial melting of juvenile crustal rocks. The Linshan high-K granitoids show relatively high whole-rock zircon saturation tempera-tures (694-889℃) and low Sr/Y ratios (0.27-21.1), indicating low pressure partial melting. Combined with other geological evidences, the Linshan high-K granitoids are suggested to have been produced by partial melting of the continental crust in a post-collision extensional environment after an arc-continent collision. Thus, the NCC did not amalgamate together until ca. 2.5 Ga. Compiled zircon U-Pb ages and Hf isotopes reveal that the ca. 2.5 Ga magmatism represents reworking of the continental crust.

关键词： granitoids petrogenesis Neoarchean North China Craton

Paleoproterozoic granitoids on Liaodong Peninsula, North China Craton

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Acta Geologica Sinica(English Edition) 2019年第5期93卷 1377-1396页

作者： ZHU Kai LIU Zhenghong XU Zhongyuan LIU Jiexun WANG Xing’an College of Geo-exploration Science and Technology Jilin UniversityChangchun 130061China College of Earth Sciences Jilin UniversityChangchun 130061China College of Geographical Sciences Northeast Normal UniversityChangchun 130024China

Paleoproterozoic granitoids are an important constituent of the Jiao-Liao-Ji Belt(JLJB). The spatial-temporal distribution and types of Paleoproterozoic granitoids are closely related to the evolution of the JLJB. In this paper, we review the field occurrence, petrography, geochronology, and geochemistry of Paleoproterozoic granitoids on Liaodong Peninsula, northeast China. The Paleoproterozoic granitoids can be divided into pre-tectonic(~2.15 Ga;peak age=2.18 Ga) and post-tectonic(~1.85 Ga) granitoids. The pre-tectonic granitoids are magnetite and hornblende-biotite monzogranites and granodiorites. Pre-tectonic monzogranites are widespread in the JLJB and have A2-type affinities. In contrast, pretectonic granodiorites are only present in the Simenzi area and have adakitic affinities. The post-tectonic granitoids consist of porphyritic monzogranite, syenite, diorite, granodiorite, quartz monzonite, monzogranite, and granitic pegmatite, which are adakitic rocks and I-, S-, and A2-type granitoids. The assemblage of pre-tectonic A2-type granitoids and adakitic rocks indicates the initial tectonic setting of the JLJB was a continental back-arc basin. The assemblage of post-tectonic adakitic rocks and I-, S-, and A2-type granitoids indicates a post-collisional setting. The 2.20-2.15 Ga A2-type granitoids and adakitic rocks were associated with the initial stage of back-arc extension, and the peak of back-arc extension is inferred from the subsequent(2.15-2.10 Ga) mafic intrusive activity. The ~1.90 Ga adakitic rocks mark the beginning of the postcollisional stage, which was followed by the intrusion of low-temperature S-and I-type granitoids. High-to low-pressure granitoids(S-type) were generated during the peak of post-collisional lithospheric delamination and asthenospheric upwelling. The emplacement of later granitic pegmatites occurred during the waning of the orogeny.

关键词： Paleoproterozoic granitoids pre-tectonic post-tectonic post-collision continental backarc basin Jiao-Liao-Ji Belt

Geochemistry,geochronology and Hf isotope of granitoids in the northern Alxa region:Implications for the Late Paleozoic tectonic evolution of the Central Asian Orogenic Belt

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Geoscience Frontiers 2020年第5期11卷 1711-1725页

作者： Xiaochen Zhao Chiyang Liu Jianqiang Wang Shaohua Zhang Yuzhao Guan College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054ShaanxiChina State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069ShaanxiChina

The tectonic setting of the northern Alxa region during the Late Paleozoic is highly controversial.The key to resolve this controversy is to recognize the Late Paleozoic magmatic processes in the northern Alxa.In this paper,we present new zircon U-Pb ages,Hf-isotopic compositions and whole-rock geochemical data of four granitoids along the Zhusileng-Hangwula Tectonic Belt in the northern Alxa region that could provide critical information about the tectonic evolution of this region.The zircon U-Pb data could be grouped as two phases:Late Devonian granite and diorite(ca.373-360 Ma),and Late Carboniferous granodiorite(ca.318 Ma).The Late Devonian granites and diorites are metaluminous to slightly peraluminous,with A/CNK and A/NK ratios of 0.90-1.11 and0.95-2.19,respectively.The Late Devonian diorites are characterized by high MgO,Cr and Ni contents and MgO#values,together with variableεHf(t)values from-1.0 to+1.3 and old TDM2 ages varied from 1283 Ma to 1426 Ma,indicating the primary magma was potentially derived from magma mixing of depleted mantle with Mesoproterozoic continental crust.Even though the Late Devonian granites yielded most positive and minor negative eHf(t)values between-1.1 to+5.7(three grains are negative)with two-stage model ages(TDM2)of 1003-1438 Ma,they display low MgO,Cr and Ni contents and MgO#values,suggesting that they were mainly derived from juvenile crustal materials,mixed with a small amount of ancient crust.The Late Carboniferous granitoids are metaluminous and medium-K calc-alkaline series,with A/CNK and A/NK ratios ranging from 0.88 to 0.95 and1.75 to 1.90,respectively.These rocks were potentially derived from juvenile crustal materials mixed with depleted mantle,as evidenced by their highεHf(t)values(+11.6 to+14.1)and young TDM2 ages(427 Ma to 586 Ma),as well as high Mg#values,and MgO,Ni and Cr contents.Our data,along with available sedimentary evidence and previous researches,indicate that the Late Devonian and Late Carboniferous rocks are arc-related granitoids under the subductio

关键词： Geochemistry U–Pb geochronology Hf isotopic composition granitoids Northern Alxa region Central Asian Orogenic Belt

Petrogenesis of the Paleoproterozoic Guandishan granitoids in Shanxi Province:Constraints from Geochemistry and Nd Isotopes

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Acta Geologica Sinica(English Edition) 2006年第6期80卷 925-935页

作者： LIU Chaohui LIU Shuwen LI Qiugen Lü Yongjun K. H. PARK Y. S. SONG The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China Department of Environmental Geosciences Pukyong National University 599-1 Dayeong-dong Nam-gu Busan 608-737 Korea

The Guandishan granitoids consist mainly of various granitoid intrusions with different scales, including the Huijiazhuang intrusion, Shizhuang intrusion and Hengjian intrusion, which were formed between 1906 Ma and 1848 Ma. On the basis of geological and petrological characteristics, these granitoids can be classified into two groups： the earlier gneissic granodiorites and monzogranites, and the later massive leuco-monzogranites. Their geochemical and Nd isotopic features indicate that they could be derived from complicated partial melting of supracrustal rocks with an affinity of continental arc materials, such as sandy shale and pelite, and with garnet, pyroxene, hornblende and plagioclase as residual phases. Biotite, feldspar and other minerals were most likely fractionated during the magma evolution. Their source may have an affinity with continental arcs, and the granitoids could be derived from the main syn-collisional to late-orogenic tectonic environment, which may be related to the final amalgamation between the Eastern and Western continental blocks in the North China Craton.

关键词： granitoids geochemistry Sm-Nd isotopes petrogenesis Paleoproterozoic Guandishan