Submit to Minerals Review for Minerals Propose a Special Issue

Journal Menu

Journal Browser

Petrogenesis, Magmatism and Geodynamics of Orogenic Belts

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Benefits of Publishing in a Special Issue
Published Papers

A special issue of Minerals (ISSN 2075-163X). This special issue belongs to the section "Mineral Geochemistry and Geochronology".

Deadline for manuscript submissions: closed (31 March 2024) | Viewed by 13959

Share This Special Issue

Special Issue Editors

Dr. Fuhao Xiong

E-Mail Website
Guest Editor

College of Earth Science, Chengdu University of Technology, Chengdu 610059, China
Interests: magmatism and tectonic evolution in orogenic belt; Paleo-Tethyan orogeny; crust–mantle interaction
Special Issues, Collections and Topics in MDPI journals

Dr. Bin Liu

E-Mail Website
Guest Editor

School of Geosciences, Yangtze University, Wuhan 430100, China
Interests: igneous petrology and geochemistry; paleo-tethyan tectono-magmatic evolution; magmatism and petroleum exploration

Special Issue Information

Dear Colleagues,

The formation of igneous rocks in orogenic belts is the response to the coupling of the crust–mantle material cycle and geodynamics. These structures represent important probes for revealing the growth mechanism of continental crust and associated deep geodynamic processes. Igneous rocks, generated in different tectonic settings including the opening and closing of oceanic basin, terranes collision and post-collisional extension, usually exhibit different rock assemblages and geochemical compositions, thus making them the key objects for tectonic reconstruction. The fact that magma sources and evolution processes play key roles in their origin is well known, however, how and to what degree do the different magma sources and magmatic evolution processes contribute to the petrological and geochemical diversity of igneous rocks in orogenic belts is debated and remains controversial. Over the past few decades, the scientific community has made a variety of breathroghs in their understanding of magma reservoirs. Unlike the conceptual melt-dominated magma chamber model, numerous geophysical and petrological studies have revealed that magma chambers mostly exist in the form of crystal-rich mush reservoirs. This new model requires us to rethink and study the evolution process and petrogenesis of igneous rocks, especially the mechanism of crust–mantle interaction in crystal mush magma. Hence, Minerals is placing an open call for original research, methods, comprehensive summary and review papers and other types of submissions for a thematic Special Issue entitled “Petrogenesis, Magmatism and the Geodynamics of Orogenic Belts”. We particularly encourage (but are not limited to) contributions of the following issues:

Magma sources and petrological diversity;
Magmatic processes in crustal magma reservoir;
Magmatic tempos in orogenic belts and their implications for crust growth;
Mafic magmatism in different geodynamic processes;
Numerical modelling approaches predicting the magmatic evolution and geochemical diversity.

Dr. Fuhao Xiong
Dr. Bin Liu
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Minerals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

magmatism
petrogenesis
magmatic process
magmatic reservoir
geodynamic
tectonic

Benefits of Publishing in a Special Issue

Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (9 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Research

24 pages, 14741 KiB

Open AccessArticle

Zircon U-Pb Geochronology, Geochemistry, and Sr-Nd-Hf Isotopic Composition of Ben Giang-Que Son Complex in the Southern Truong Son Belt: Implications for Permian–Triassic Tectonic Evolution

by Thuy Thi Bich Nguyen, Pham Trung Hieu, Qian Xin, Bui The Anh, Nguyen Thi Xuan, Pham Minh and Ho Thi Thu

Minerals 2024, 14(6), 569; https://doi.org/10.3390/min14060569 - 29 May 2024

Viewed by 812

Abstract

The magmatic rocks of the Ben Giang-Que Son complex exposed in the southern part of the Truong Son belt have petrographic compositions including gabbro, gabbrodiorite, granodiorite, and granite. Geochemically, the magmatic rocks are of subalkaline affinity and belong to the high-K calc-alkaline series. All analyzed samples contain hornblende and biotite as mafic minerals and are defined as metaluminous with a aluminum saturation index of <1.1. Chondrite-normalized rare earth element diagrams are characterized by fractionation between light and heavy rare earth elements and show small to moderate negative Eu anomalies (Eu/Eu* = 0.81–0.44). Primitive mantle-normalized trace element patterns exhibit enrichment in LILEs such as Rb, K, U, and especially Pb and depletion of HFSEs (Nb, Ta, and Ti), indicating arc-magma. The BG-QS gabbro and gabbrodiorite have low Cr, Co, and Ni and display enrichment in ⁸⁷Sr/⁸⁶Sr (0.7084 to 0.7147), Ꜫ_Nd(t) (−0.5 to −1.9), and positive Ꜫ_Hf(t) (+2.4 to 4.5), suggesting generation from the enriched mantle source. The BG-QS diorite and granodiorite contain small mafic enclaves, have a wide range of SiO₂ contents and enrichment in Sr-Nd isotopes (⁸⁷Sr/⁸⁶Sr = 0.7109–0.7178; Ꜫ_Nd(t) = −3.3 to −3.7), and display high Mg# (43–51). All these features indicate that they were formed by the mixing of magmas, which originated from an enriched mantle source and the pre-existing juvenile mafic lower crust. The whole-rock Nd and zircon Hf model ages are of 1160–760 Ma. The Ben Giang-Que Son complex yields LA-ICP-MS zircon U-Pb ages of 285 ± 3.1 and 278 ± 3.5 Ma that corresponds to the Cisuralian epoch (early Permian), which is linked to the subduction and amalgamation of the Indochina and South China blocks due to the closing a branch of the Paleotethys along the Song Ma suture. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Figure 1

22 pages, 25391 KiB

Open AccessArticle

Petrogenesis and Tectonic Implications of the Oligocene Dalongtan Shoshonitic Syenite Porphyry in Central Yunnan, Southeastern Tibetan Plateau: Constraints from Geochronology, Geochemistry and Sr-Nd-Hf Isotopes

by Hang Yang, Anlin Liu, Peng Wu and Feng Wang

Minerals 2024, 14(3), 282; https://doi.org/10.3390/min14030282 - 8 Mar 2024

Viewed by 1152

Abstract

Shoshonitic rocks are widely distributed in post-collisional settings and provide key information on deep geodynamic mechanisms and magmatic evolution. In this paper, we present petrographic, zircon U-Pb age-related, trace elemental, Hf isotopic, bulk-rock elemental, and Sr-Nd isotopic data of the Dalongtan shoshonitic syenite porphyries (DSSPs) in central Yunnan, southeastern Tibet. The DSSPs formed at 33.2 ± 0.3 Ma in a post-collisional setting. They define linear trends on Harker diagrams, and they display similar trace element patterns and enriched bulk-rock Sr-Nd isotopes [(⁸⁷Sr/⁸⁶Sr)_i = 0.70964–0.70968, ε_Nd(t) = −12.9 to −12.7] and zircon Hf isotopes (ε_Hf(t) = −15.7 to −13.1) to the coeval mantle-derived potassic mafic rocks. This suggests that the DSSPs were fractionated from the lithospheric mantle-derived mafic magmas. The DSSPs, along with the coeval felsic and mafic magmatic rocks (37.2–32.3 Ma), exhibit a planar distribution on the SE Tibet and predate the left-lateral shearing of the Ailaoshan–Red River shear zone (ARSZ) (32–22 Ma), suggesting that there are no genetic relationships between them. The DSSPs have geochemical characteristics similar to those of A-type granites, with high total alkalinity (10.39–11.17 wt.%), HFSE concentrations (Zr + Nb + Ce + Y = 890.2–1054.3 ppm), Ga/Al ratios (10,000 × Ga/Al = 2.95–3.46), whole-rock zircon saturation temperatures (906–947 °C), and oxygen fugacity (ΔFMQ = +3.30–+4.65), indicating that they are products of the high-temperature melting of the lithosphere as a result of asthenosphere upwelling in extensional settings. Based on our data and regional observations, it is proposed that the generation of the DSSPs may be linked to the convective thinning of the thickened lithospheric mantle following the India–Asia collision. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Figure 1

23 pages, 7384 KiB

Open AccessArticle

Petrogenesis and Tectonic Significance of Early Permian Intermediate–Felsic Rocks in the Southern Beishan Orogen, Northwest China: Geochronological and Geochemical Constraints

by Runwu Li, Shangguo Su, Huiyi Sun, Ruibin Liu and Yutian Xia

Minerals 2024, 14(1), 114; https://doi.org/10.3390/min14010114 - 22 Jan 2024

Cited by 3 | Viewed by 1560

Abstract

Permian intermediate–felsic igneous rocks, widely distributed in the southern Beishan orogen, provide crucial constraints on the geodynamic process of the late Paleozoic Paleo-Asian Ocean. New zircon U–Pb dating using LA–ICP–MS determines the age of the northern Qingshan diorites, the Heishantou quartz diorites, and the southern Qingshan biotite granodiorites at 300 Ma, 294 Ma, and 291–286 Ma, respectively. Their whole-rock compositions exhibit arc-like geochemical features. Moreover, their zircon trace elements show the characteristics of continental arc zircons. The diorites, characterized by low SiO₂, high MgO with Mg# (50–52), and low Cr, Co, and Ni, display enrichment in Sr-Nd-Hf isotopes (⁸⁷Sr/⁸⁶Sr = 0.7060 to 0.7061; ℇ_Nd(t) = −1.4 to −1.7; ℇ_Hf(t) = −4.7 to −0.6), originating from the fractionation process of magma derived from the enriched mantle. The quartz diorites show moderate SiO₂ and variable MgO (2.75–3.84 wt%) and exhibit enrichment in Sr-Nd (⁸⁷Sr/⁸⁶Sr = 0.7048–0.7050; ℇ_Nd(t) = −1.5–+0.9) and depletion in zircon Hf isotopes (ℇ_Hf(t) = 3.8 to 7.8). Combined with their high Y (20.0–21.0 ppm) and low (La/Yb)_N (6.0 to 17.2), we conclude that they originated from the juvenile lower crust previously influenced by oceanic sediments, with the input of enriched mantle-derived materials. The biotite granodiorites display low A/CNK (0.91–0.97), 10000*Ga/Al (1.8–1.9), and Ti-in-zircon temperatures (average 711 °C), indicating that they are I-type granitoids. These rocks show enrichment in Sr-Nd isotopes (⁸⁷Sr/⁸⁶Sr = 0.7054 to 0.7061; ℇ_Nd(t) = −2.0 to −1.6) and many variable zircon Hf isotopes (ℇ_Hf(t) = −2.3 to +4.5). Geochemical studies indicate that they originate from the mixing of magmas derived from the enriched mantle and preexisting juvenile lower crust. All these data imply the existence of oceanic subduction in southern Beishan during the early Permian. Integrating these results with previous studies, it is inferred that the retreating subduction of the Liuyuan Ocean contributed to early Permian intermediate–felsic rocks becoming widespread in the Shibanshan unit, the southernmost part of the Beishan orogen, and also why the Paleo-Asian Ocean in southern Beishan did not close during the early Permian. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Graphical abstract

15 pages, 9365 KiB

Open AccessArticle

Petrogenesis and Geodynamic Implications of Cretaceous Nb-Enriched Mafic Dykes in the East Kunlun Orogen, Northern Tibet Plateau: Constraints from Geochronology, Geochemistry and Sr-Nd Isotopes

by Zhiqiang Chu, Hu Zhou, Mingchi Wang, Jiaming Zhou and Fuhao Xiong

Minerals 2024, 14(1), 89; https://doi.org/10.3390/min14010089 - 12 Jan 2024

Viewed by 1351

Abstract

There is a magmatic lull period in the East Kunlun orogen (EKO) during the Jurassic to the Cretaceous. However, due to the lack of records of magmatic activity restricts our understanding of the late Mesozoic magmatic-tectonic evolution of the EKO. Herein, an integrated study of geochronology, whole-rock geochemistry and Sr-Nd isotopes were conducted for the Cretaceous mafic dykes in the EKO, Northern Tibet Plateau, to reveal their petrogenesis and geodynamic implications. LA-ICP-MS Zircon U-Pb dating reveals that the studied mafic dykes comprising diabase and diabase porphyry emplaced at ca. 80.9 ± 0.8 Ma. The Cretaceous mafic dykes have low contents of SiO₂ (46.36 wt.%~47.40 wt.%) but high contents of MgO (6.79 wt.%~7.38 wt.%), TiO₂ (1.91 wt.%~2.13 wt.%), Nb (12.4~18.3 ppm) and Nb/U ratio (31~39), resembling Nb-enriched mafic dykes. They exhibit chondrite-normalized rare earth element (REE) and primitive mantle-normalized trace element patterns, remarkably similar but not identical to the oceanic island basalts (OIB). The moderate REE fractionation ((La/Yb)_N = 3.55~5.37), weak negative Eu anomalies (δEu = 0.87~0.97) and relative enrichment of Rb, Ba, K, as well as high contents of Cr and Ni and slightly depleted Sr-Nd isotopes (εNd(t) = −0.18~1.33), suggest that the studied dykes originate from a partial melting of spinel lherzolite and a little of garnet which was previously modified by subducted sediments. Combined with other evidence, we propose that the studied Cretaceous Nb-enriched mafic dykes in the Northern Tibet Plateau were formed in the intraplate setting, which may be a partial melting of the enriched mantle in the lower lithosphere caused by the activity of the East Kunlun strike-slip fault. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Figure 1

17 pages, 5448 KiB

Open AccessEditor’s ChoiceArticle

Mineralogical Constraints on Magma Recharge and Mixing of the Post-Collisional Potassic Volcanic Rocks in Dahongliutan, NW Tibetan Plateau

by Wenjian Yang, Bo Zhao, Hongmei Yu, Jiandong Xu, Feixiang Wei and Xiaoge Cui

Minerals 2023, 13(12), 1463; https://doi.org/10.3390/min13121463 - 22 Nov 2023

Viewed by 1276

Abstract

Post-collisional potassic magmatic rocks are widely distributed in the northwestern Tibetan Plateau, yet their magmatic processes remain poorly understood. Here, we present a comprehensive analysis of the whole-rock major and trace elements, as well as the mineral textures and chemistry of the Dahongliutan volcanic rocks in the NW Tibetan Plateau, aiming to reveal the magmatic processes prior to eruption and speculate on the triggering mechanism. The results show that the Dahongliutan volcanic rocks are potassic trachyandesites, which undergo polybaric crystallization during magma ascension. The phenocrysts in these potassic rocks exhibit various textural and compositional zoning styles. The green cores of green-core clinopyroxenes show textural (e.g., resorption texture) and chemical (Fe-rich) disequilibrium with the host rock compositions, suggesting that they may be antecrysts and crystallized from early batches of more evolved magmas. Additionally, alkali feldspar phenocrysts also display disequilibrium characteristics (e.g., overgrowth rim and sieve texture), indicating hot mafic magma recharge and mixing in the magma plumbing system. Therefore, we conclude that the disequilibrium textural and compositional features of green-core clinopyroxene and alkali feldspar phenocrysts provide evidence of magma recharge and mixing prior to eruption. Furthermore, it is likely that the eruption of the Dahongliutan volcano was triggered by magma recharge. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Figure 1

16 pages, 15379 KiB

Open AccessArticle

Geochemistry and Zircon U–Pb Geochronology of the Wugongshan Granites in the Northwestern Jiangxi Area, China: Implications for the Paleozoic Tectonic Development of South China

by Guangqin Yang, Yaoyao Zhang, Kai Liu, Yi Zhou, Shuxun Wang and Hailong Huo

Minerals 2023, 13(11), 1427; https://doi.org/10.3390/min13111427 - 9 Nov 2023

Cited by 1 | Viewed by 1513

Abstract

The properties of the Caledonian orogeny along the transition belt of the Yangtze and Cathaysia blocks have received much attention in recent years. The widespread Early Paleozoic granites provide critical geological clues for unraveling the tectonic evolution and geodynamic processes of the South China Continent (SCC). Here we present new zircon U–Pb chronology, whole-rock major and trace elements, in situ Hf isotopes for Paleozoic granites, i.e., the Wugongshan granites in the northwest Jiangxi province, and aim to explore the magmatism and properties of the Caledonian orogeny involved in their formation. Our new data show that the Wugongshan granites were emplaced during the Early Silurian Period (442–438 Ma). The Paleozoic Wugongshan granites belong to S-type muscovite-bearing peraluminous granites (MPG) and show a single origin. The Wugongshan granites exhibit negative εHf(t) values (−11.56 to −6.19) and TDM2 model ages of 2148–1809 Ma, indicating their derivation from an ancient crustal source, through partial melting of ancient crustal material. The Wugongshan granitic magmatism is probably being generated in an extensional environment related to an intracontinental orogeny setting. It is inferred that the Paleozoic tectonic–magmatic event in the Wugongshan area was associated with the oceanic–continental convergence of the Paleo-Tethys Ocean. The Wugongshan granites highlight the intracontinental magmatism in the Early Paleozoic orogeny in the SCC. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Figure 1

19 pages, 16233 KiB

Open AccessArticle

Late Cretaceous-Paleocene Arc and Back-Arc System in the Neotethys Ocean, Zagros Suture Zone

by Yousif Mohammad, Kurda Abdulla and Hossein Azizi

Minerals 2023, 13(11), 1367; https://doi.org/10.3390/min13111367 - 26 Oct 2023

Cited by 4 | Viewed by 1574

Abstract

The Bulfat Igneous Complex comprises the Bulfat and Walash groups and is situated in the Zagros Suture Zone, in the junction of Arabian and Eurasian plates. Zircon U-Pb data indicat an age of 63.7 ± 1.5 Ma for the trondhjemite rocks within the Bulfat group. Walash group is primarily composed of basalt to andesite rocks, interbedded with sedimentary rocks. Zircon U-Pb dating yields an age of 69.7 ± 2.7 Ma for the Walash group. Whole rocks chemistry shows that the Bulfat rocks have affinity to MORB and calc alkaline series but Walsh are mainly plot in the calc alkaline field. Whole rocks Sr-Nd isotope ratios show that the ¹⁴³Nd/¹⁴⁴Nd (i) changes from 0.51243 to 0.52189 and 87Sr/86Sr(i) ratios vary from 0.70345 to 0.7086. The calculated εNd(t) values, based on the CHUR, yield predominantly high positive values ranging from +6 to +8 for most samples. However, a few samples exhibit lower values (+2 to +3). Our data suggest that the interaction between lithospheric (depleted mantle, MORB-Like) and asthenospheric mantle (OIB-like) melts significantly controlled the magmatic evolution of the Bulfat group. The strong positive εNd(t) values (ranging from +6 to +8) align more consistently with a highly depleted lithospheric mantle source for the Walsh group. Therefore, the gradual transition from an arc signature at 70 Ma to a MORB signature around 63 Ma, occurred over a relatively short period of about 10 million years, and indicates the presence of an arc and back-arc system in the Neotethys ocean before the collision of the Arabian and Iran plates during the Cenozoic. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Figure 1

18 pages, 13063 KiB

Open AccessArticle

Petrogenesis and Geodynamic Significance of the Early Triassic Nanpo Adakitic Pluton of the Luang Prabang-Loei Tectonic Belt (Northwestern Laos) in the East Tethys Domain: Constraints from Zircon U-Pb-Hf Isotope Analyses and Whole-Rock Geochemistry

by Hui Li, Jie Gan, Zhengwei He, Yu Gan, Bin Wang, Yong Li and Wei Jiang

Minerals 2023, 13(6), 821; https://doi.org/10.3390/min13060821 - 16 Jun 2023

Cited by 2 | Viewed by 1594

Abstract

Adakites are magmatic rocks with specific geochemical characteristics and specific dynamics that provide important clues to understanding the magmatic-tectonic evolution of orogenic belts. We studied the Early Triassic Nanpo adakitic pluton of the Luang Prabang-Loei tectonic belt in the Eastern Tethys domain (Laos Sarakan) using detailed petrological, zircon U-Pb chronological, whole-rock geochemical, and zircon Lu-Hf isotope studies to constrain their petrogenesis. The rocks are predominantly diorites and granodiorites with Early Triassic zircon U-Pb emplacement ages ranging from 247.9 ± 1.0 to 249.0 ± 2.4 Ma. Moderate SiO₂ (56.26–65.95 wt%) and Na₂O (3.24–5.00 wt%) contents, with Na₂O/K₂O values between 1.76 and 2.51 and A/CNK values between 0.81 and 0.94, indicate that the rocks belong to the metaluminous calc-alkaline rock series. The high Sr content (590–918 ppm), low Y (6.30–11.89 ppm) and Yb (1.99–3.44 ppm) contents, intermediate Mg# (42–50) values, and high Sr/Y and (La/Yb) _N ratios (Sr/Y = 24–41, (La/Yb) _N = 6.84–13.8) are typical for adakites. Zircon Hf isotope analysis shows a significant variation in the εHf(t) values (6.7–12.0), with a mean value of 9.4 and a T_DM2 of 512–845 Ma. Geochemical evidence indicates that the Nanpo adakitic rock was formed by the partial melting of the thickened lower crust in the plate-breaking environment and has an important contribution to the underplated mantle-derived magma. We propose that the Early Triassic adakites in the Luang Prabang-Loei tectonic belt formed during the transition from subduction to a continental collision, and the mixing of crust- and mantle-derived magmas is the main mechanism for the growth of continental crust in the Paleo-Tethys orogenic belt of southeastern Asia. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Figure 1

20 pages, 14088 KiB

Open AccessArticle

Late Ordovician High Ba-Sr Intrusion in the Eastern North Qilian Orogen: Implications for Crust–Mantle Interaction and Proto-Tethys Ocean Evolution

by Shaoqing Zhao, Lianfu Hai, Bin Liu, Huan Dong, Chao Mei, Qinghai Xu, Caixia Mu and Xiangcheng Wei

Minerals 2023, 13(6), 744; https://doi.org/10.3390/min13060744 - 30 May 2023

Cited by 1 | Viewed by 1607

Abstract

High Ba-Sr granitic rocks are widespread in Phanerozoic orogenic systems, and their petrogenesis is important for revealing the evolutionary process of the Proto-Tethys Ocean in the North Qilian orogenic belt. This paper presents a combination of zircon U-Pb age, whole-rock major and trace element concentrations, and Sr-Nd-Hf isotopic data for Caowa high Ba-Sr dioritic intrusion from the eastern part of the North Qilian orogenic belt, aiming to decipher its petrogenesis and tectonic setting. LA-ICP-MS zircon U-Pb dating yield an emplacement age of 450 ± 2 Ma for the Caowa intrusion, indicating a magmatic activity of the Late Ordovician. The Caowa quartz diorites contain moderate contents of SiO₂, MgO, Mg^#, and resultant high concentrations of Na₂O + K₂O, Fe₂O₃^T, and Al₂O₃, displaying calc-alkaline and metaluminous characteristics. The studied samples have relatively elevated Ba (up to 1165 ppm) and Sr (561 to 646 ppm) contents, with obvious enrichment in LILEs (e.g., Ba, Th, U) and depletions in HFSEs (e.g., Nb, Ta, Ti), resembling those of typical high Ba-Sr granitoids in subduction zones. Together with enriched Sr-Nd isotopic composition [(⁸⁷Sr/⁸⁶Sr)_i = 0.7082–0.7086, ε_Nd(t) = −5.1 to −4.9], and the wide ranges of zircon ε_Hf(t) values (−13.2 to +8.5), it suggests that these high Ba-Sr quartz diorites were derived from a mixture magma source between the ancient crust materials and the enriched lithospheric mantle metasomatized by fluid released from subducted oceanic crust or sediment. Taking into account the ophiolites, high pressure metamorphic rocks, and arc magmatic rocks in the region, we infer that due to the influence of the northward subduction of the Qilian Proto-Tethys Ocean, the Laohushan oceanic crust of the North Qilian back-arc basin was subducted during the Late Ordovician and resulted in extensive metasomatism of lithospheric mantle by fluids derived from oceanic crust or sediments, and the Caowa high Ba-Sr quartz diorites were generated in the process of crust–mantle interaction during the Late Ordovician. Full article

(This article belongs to the Special Issue Petrogenesis, Magmatism and Geodynamics of Orogenic Belts)

► Show Figures

Journal Menu

Journal Browser

Petrogenesis, Magmatism and Geodynamics of Orogenic Belts

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (9 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI