Special Issue "Petrogenesis, Geochronology, Mineralization and Geochemistry of Granite Rocks"

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

Deadline for manuscript submissions: 31 December 2023 | Viewed by 7851

Special Issue Editors

School of Earth Sciences, Key Laboratory of Mineral Resources in Western China (Gansu Province), Lanzhou University, Lanzhou 730000, China
Interests: petrogenesis; geochronology; geochemistry; granite rocks
Dr. Jiaolong Zhao
E-Mail Website
Guest Editor
School of Earth Sciences, Key Laboratory of Mineral Resources in Western China (Gansu Province), Lanzhou University, Lanzhou 730000, China
Interests: geochemistry; petrogenesis
School of Earth Sciences, Key Laboratory of Mineral Resources in Western China (Gansu Province), Lanzhou University, Lanzhou 730000, China
Interests: low-temperature thermochronology; continent weathering

Special Issue Information

Dear Colleagues,

Granite is an important component of continental crust, recording information about its formative time and mechanism in the evolution processes of mantle and crust. A number of studies on granites have taken place over the years, focusing on granite types, primary magma temperature and pressure, crystal differentiation, evolution of crust and mantle, tectonic setting, etc. Significant work have also been carried out on granite classification based on geochemistry and/or formation. The former, MISA-type classification (mantle-derived-type, infracrustal or igneous-type, supracrustal or sedimentary-type, and alkaline, anorogenic or anhydrous-type), based on primary magma sources, is widely accepted; the latter is classified as metaluminous, peraluminous, and peralkaline granitoids based on chemical components; or, based on the tectonic settings, as orogenic granite (on the ocean and continental arc, continent collisional belts), post-orogenic granite (on the areas of upwelling or collapse/delamination), and non-orogenic granite (on the continental rift valley, hotspot, mid-ocean ridge, island arc, etc.). For highly evolved juvenile granites, there is no clear geochemical limit, so it is difficult to fully understand granite formation. In these types, the formation of A-type granite is a topic of great dispute but represents the strongest possibility to indicate a geodynamic setting. Mafic microgranular enclave (MME) in the granitoids is a common phenomenon that is useful to comprehend granitoid formation. At the same time, large-scale rare element ore deposits are controlled by granitoids. The partition of the tetrad effect of REE distribution has a close relationship with mineralization. This Special Issue will focus on granitoids’ formation time, geochemistry characteristics, geodynamic settings, and mineralization to decipher the growth and evolution of the continental crust and mineral resources.

Prof. Dr. Chengjun Zhang
Dr. Jiaolong Zhao
Dr. Pengju He
Guest Editors

Manuscript Submission Information

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Keywords

  • granite rocks
  • petrogenesis
  • geochronology
  • geochemistry characteristics
  • mineralization

Published Papers (10 papers)

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Research

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Article
Petrogenesis of Late Cretaceous Muscovite-Bearing Peraluminous Granites in the Youjiang Basin, South China Block: Implications for Tin Mineralization
Minerals 2023, 13(9), 1206; https://doi.org/10.3390/min13091206 - 13 Sep 2023
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Abstract
Most primary Sn deposits worldwide are associated with muscovite-bearing peraluminous granites, commonly believed to originate from the partial melting of metasedimentary rocks. We studied the whole-rock geochemistry and Sm–Nd isotopes of Late Cretaceous (~90 Ma) Laojunshan muscovite-bearing peraluminous granites in the Youjiang Basin, [...] Read more.
Most primary Sn deposits worldwide are associated with muscovite-bearing peraluminous granites, commonly believed to originate from the partial melting of metasedimentary rocks. We studied the whole-rock geochemistry and Sm–Nd isotopes of Late Cretaceous (~90 Ma) Laojunshan muscovite-bearing peraluminous granites in the Youjiang Basin, South China Block. The globally significant Dulong tin mineralization was co-genetic with the Laojunshan muscovite-bearing monzogranites. The Laojunshan granites exhibit slightly higher εNd(t) values than the Precambrian basement, indicating a hybrid crustal source comprising both Precambrian rock and juvenile components. Characterized by weakly peraluminous compositions, these granites display highly evolved geochemical features: notably low levels of Ca, P, Mg, Fe, and Ti contents, elevated Si content, a high FeOT/MgO ratio, and a low Zr/Hf ratio. These distinctive geochemical features can be attributed to the differentiation of plagioclase, biotite, and zircons, with the remarkably low Nb/Ta and K/Rb ratios further suggesting a fluid exsolution process. The geochemical data propose that tin-enriched Laojunshan granites originate from mineral differentiation and fluid exsolution of crust-derived melts during magmatic evolution. By integrating these novel findings with existing data on coeval muscovite-bearing granites co-genetic with tin mineralization in the Youjiang Basin, it is deduced that these granites share a unified origin. Their genesis can be attributed to mineral differentiation and fluid exsolution of crust-derived melts rather than a direct melting of metasedimentary rocks. Full article
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Article
Petrogenesis of Devonian and Permian Pegmatites in the Chinese Altay: Insights into the Closure of the Irtysh–Zaisan Ocean
Minerals 2023, 13(9), 1127; https://doi.org/10.3390/min13091127 - 25 Aug 2023
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Abstract
Owing to tectonic, magmatic, and metamorphic controls, pegmatites associated with different spatiotemporal distributions exhibit varying mineralisation characteristics. The petrogenesis of pegmatites containing rare metals can improve the understanding of geodynamic processes in the deep subsurface. In order to understand the difference of petrogenesis [...] Read more.
Owing to tectonic, magmatic, and metamorphic controls, pegmatites associated with different spatiotemporal distributions exhibit varying mineralisation characteristics. The petrogenesis of pegmatites containing rare metals can improve the understanding of geodynamic processes in the deep subsurface. In order to understand the difference of petrogenesis between Devonian and Permian pegmatites, zircon U-Pb geochronological and Hf-O isotope analyses were performed on samples of the Jiamanhaba, Amulagong, and Tiemulete pegmatites from the Chinese Altay. According to the results obtained, the Amulagong and Tiemulete pegmatites were formed during the Devonian, and samples that were analysed yielded zircon U-Pb ages of 373.0 ± 7.8 and 360 ± 5.2 Ma, respectively. Samples from these pegmatites produced εHf(t) values of 2.87–7.39, two-stage model ages of 900–1171 Ma and δ18O values of 9.55‰–15.86‰. These results suggest that the pegmatites were formed via an anatexis of mature sedimentary rocks deep in the crust. In contrast, the Jiamanhaba pegmatite was formed during the Permian, and its samples produced εHf(t) and δ18O values of 2.87–4.94 and 6.05‰–7.32‰, respectively, which indicate that the associated magma contained minor amounts of mantle/juvenile materials. The petrogenesis of pegmatites containing rare metals can reveal tectonic settings of their formation. A combination of data that were generated in the present study and existing geochronological and Hf-O isotope data for felsic igneous and sedimentary rocks in the Chinese Altay shows that the εHf(t) sharply increased while the δ18O suddenly decreased between Late Carboniferous and Early Permian. These changes highlight a tectonic transformation event during this critical period. This tectonic event promoted mantle–crustal interactions, and thus, it was probably linked to assemblages of the Altay orogen and the Junggar Block. The present study provides evidence that the Irtysh–Zaisan Ocean probably closed during the Late Carboniferous (~300 Ma). Full article
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Article
Effects of Metasomatism on Granite-Related Mineral Systems: A Boron-Rich Open Greisen System in the Highiş Granitoids (Apuseni Mountains, Romania)
Minerals 2023, 13(8), 1083; https://doi.org/10.3390/min13081083 - 14 Aug 2023
Viewed by 473
Abstract
Greisenization is typically linked with highly fractionated granites and is often associated with hydrothermal vein systems. Late to postmagmatic metasomatic processes involve the enrichment of volatile components such as boron and halogens as well as several metallic elements. The purpose of this study [...] Read more.
Greisenization is typically linked with highly fractionated granites and is often associated with hydrothermal vein systems. Late to postmagmatic metasomatic processes involve the enrichment of volatile components such as boron and halogens as well as several metallic elements. The purpose of this study is to reveal the main metasomatic effects and paragenetic sequences of the related mineralizations in Highiş granitoids, Romania. In a natural outcrop, more than 30 samples were collected from granitoids, felsic veins, and country rocks. We carried out a detailed mineralogical and petrological characterization of carefully selected samples using X-ray powder diffractometry, electron microprobe analysis, and microscopic methods together with K–Ar ages of whole rocks and K-bearing minerals. Several characteristic features of albitization, sericitization, tourmalinization, epidotization, and hematitization were recognized in the studied samples. Crystallization of quartz, K-feldspar, and magnetite represents the first stage during the magmatic-hydrothermal transition. The mineral assemblage of albite, sericite, schorl, and quartz originates from the early and main stages of greisenization. While the subsequent mineral assemblages, which predominantly include dravite, specular hematite, and epidote, are closely related to the late vein-depositing stage. We propose that the study area could belong to a boron-rich open greisen system in the apical portion of Guadalupian A-type granite. Based on a new hypothesis, the previously published Permian crystallization ages (between ~272 Ma and ~259 Ma) could be homogenized and/or partially rejuvenated during the hydrothermal mineralization processes due to uraniferous vein minerals. Additionally, the Highiș granite-related system suffered a Cretaceous thermal overprint (between ~100 Ma and ~96 Ma). The results may help to understand the evolution of highly evolved granite intrusions worldwide and improve our knowledge of the effect of hydrothermal mineralization processes on the emplacement ages. Full article
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Article
Magmatic Evolution and Rare Metal Mineralization in Mount El-Sibai Peralkaline Granites, Central Eastern Desert, Egypt: Insights from Whole-Rock Geochemistry and Mineral Chemistry Data
Minerals 2023, 13(8), 1039; https://doi.org/10.3390/min13081039 - 04 Aug 2023
Viewed by 408
Abstract
The Ediacaran peralkaline granites, which were emplaced during the post-collisional tectonic extensional stage, have a limited occurrence in the northern tip of the Nubian Shield. In this contribution, we present new mineralogical and geochemical data of Mount El-Sibai granites from the Central Eastern [...] Read more.
The Ediacaran peralkaline granites, which were emplaced during the post-collisional tectonic extensional stage, have a limited occurrence in the northern tip of the Nubian Shield. In this contribution, we present new mineralogical and geochemical data of Mount El-Sibai granites from the Central Eastern Desert of Egypt. The aim is to discuss their crystallization condition, tectonic setting, and petrogenesis as well as the magmatic evolution of their associated mineralization. Mount El-Sibai consists of alkali-feldspar granites (AFGs) as a main rock unit with scattered and small occurrences of alkali-amphibole granites (AAGs) at the periphery. The AAG contain columbite, nioboaeschynite, zircon and thorite as important rare metal-bearing minerals. Geochemically, both of AFG and AAG exhibit a highly evolved nature with a typical peralkaline composition (A/CNK = 0.82–0.97) and formed in within-plate anorogenic setting associated with crustal extension and/or rifting. They are enriched in some LILEs (Rb, K, and Th) and HFSEs (Ta, Pb, Zr, and Y), but strongly depleted in Ba, Sr, P and Ti with pronounced negative Eu anomalies (Eu/Eu* = 0.07–0.34), consistent with an A-type granite geochemical signature. The calculated TZrn (774–878 °C) temperatures indicate that the magma was significantly hot, promoting the saturation of zircon. The texture and chemistry of minerals suggest that they were crystallized directly from a granitic magma and were later subject to late- to post-magmatic fluids. Both granitic types were most likely generated through partial melting of a juvenile crustal source followed by magmatic fractionation. The lithospheric delamination is the main mechanism which causes uplifting of the asthenospheric melts and hence provides enough heat for crustal melting. The produced parent magma was subjected to prolonged fractional crystallization to produce the different types of Mount El-Sibai granites at different shallow crustal levels. During magma fractionation, the post-magmatic fluids (especially fluorine) contribute significantly to the formation of rare metal mineralization within Mount El-Sibai granites. Full article
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Article
Genesis and Geological Significance of Siderite in the First Member of the Nantun Formation of Dongming Sag, Hailar Basin
Minerals 2023, 13(6), 804; https://doi.org/10.3390/min13060804 - 13 Jun 2023
Viewed by 543
Abstract
Multiple siderite beds developed in the first member of the Lower Cretaceous Nantun Formation (K1n1) in the basin. The results show that the siderites in K1n1 of the study area are mostly stratiform or massive, with [...] Read more.
Multiple siderite beds developed in the first member of the Lower Cretaceous Nantun Formation (K1n1) in the basin. The results show that the siderites in K1n1 of the study area are mostly stratiform or massive, with three micromorphological features (dense micronized crystals, bands, and paragenesis with quartz and calcite). The siderite beds are mainly composed of siderite, clay, quartz, calcite, and feldspar. Under the microscope, charcoal, algal fossils, granular pyrite crystals, vein-like siliceous bands, etc., were observed. The oxides in the siderite beds include Fe2O3, SiO2, Al2O3, etc. The trace elements are typically characterized by high Mn and Be contents; low Sr/Ba, Th/U, and Al/Ti ratios; and high V/Cr ratios. These indicate weakly reducing, freshwater depositional paleoenvironments. The δ13Cv-PDB and δ18Ov-PDB values of siderite are −0.20–1.11‰ (mean: 0.62‰) and −18.22‰ to −10.14‰ (mean: −14.23‰), respectively, which shows that the carbon in siderite came mainly from carbonate dissolution. The Fe-bearing rocks in the source area migrated to the basin after undergoing physical and chemical weathering, and when the resultant Fe2+ concentration reached saturation, Fe2+ combined with CO32− in the water bodies to form authigenic siderite. Full article
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Article
The Paleoproterozoic Evolution of Basement Rocks of the Taebaeksan Basin, Korean Peninsula, and Their Correlation to Those of the Paleoproterozoic Massifs in the Korean Peninsula
Minerals 2023, 13(6), 752; https://doi.org/10.3390/min13060752 - 31 May 2023
Cited by 1 | Viewed by 769
Abstract
The Korean Peninsula mainly comprises the Paleoproterozoic Gwanmo, Nangnim, Gyeonggi, and Yeongnam massifs from north to south. The Paleoproterozoic basement is rarely exposed in the Paleozoic Taebaeksan basin, which is located in the northeastern part of the Okcheon belt between the Gyeonggi and [...] Read more.
The Korean Peninsula mainly comprises the Paleoproterozoic Gwanmo, Nangnim, Gyeonggi, and Yeongnam massifs from north to south. The Paleoproterozoic basement is rarely exposed in the Paleozoic Taebaeksan basin, which is located in the northeastern part of the Okcheon belt between the Gyeonggi and Yeongnam massifs. One of the most important issues in the tectonic interpretation of the Korean Peninsula is whether Paleoproterozoic rocks in the Taebaeksan basin have an affinity with those in the Gyeonggi or Yeongnam massifs. To solve this problem, we focused on the petrogenesis of the Imgye gabbroic diorite, Jungbongsan granite, and Jangsan quartzite in the Imgye area of the Taebaeksan basin. The Imgye gabbroic diorite shows mafic to intermediate compositions with slightly enriched LREEs compared to HREEs, slightly positive Rb, K, and Pb anomalies, and negative Ta, Nb, and P anomalies. The Imgye gabbroic diorite formed in a volcanic arc tectonic setting. The geochemical compositions of the Jungbongsan granite show enriched LREEs compared to HREEs with negative Eu anomalies, and reveal strong positive Rb, Th, K, and Pb anomalies with negative Ba, Ta, Nb, Sr, P, Eu, and Ti anomalies. This Jungbongsan granite also formed in an arc tectonic setting like the Imgye gabbroic diorite. LA-ICP-MS zircon age dating of the Imgye gabbroic diorite gives an intrusion age of 1948 ± 21 Ma, whereas SHRIMP U–Pb zircon age dating on the Jungbongsan granite yields an emplacement age of 1873 ± 14 Ma. The εHf(t) values of the Imgye gabbroic diorite are from 3.5 to 9.7, whereas those of the Jungbongsan granite are from −2.9 to 0.6. These data imply that the Imgye gabbroic diorite formed from a depleted mantle in the arc tectonic environment, whereas the Jungbongsan granite formed by reworking pre-existing crust material in the arc environment. The detrital zircons in the Jangsan quartzite show ages ranging from 3.06 to 1.85 Ga, with a peak concentration of ca. 2.5 Ga. Previous studies have suggested that the northern Gyeonggi and Nangnim massifs underwent collision-related magmatism and metamorphism at ca. 1.93–1.90 Ga, and then post-collisional magmatism and metamorphism at ca. 1.89–1.83 Ga, whereas the southern Gyeonggi massif underwent subduction-related magmatism and metamorphism at ca. 1.94–1.92 Ga, and then post-collision-related magmatism and metamorphism at ca. 1.84–1.78 Ga. By contrast, subduction-related events were recognized in the northern Yeongnam massif at ca 2.02–1.96 Ga and 1.90–1.85 Ga. This work, combined with the previous studies, suggests that the Paleoproterozoic basement in the Imgye area of the Taebaeksan basin can be correlated with the Paleoproterozoic basement of the northern Yeongnam massif rather than with those of the Nangnim and Gyeonggi massifs. Full article
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Article
Low-Temperature Fluorocarbonate Mineralization in Lower Devonian Rhynie Chert, UK
Minerals 2023, 13(5), 595; https://doi.org/10.3390/min13050595 - 25 Apr 2023
Viewed by 818
Abstract
Rare earth element (REE) fluorocarbonate mineralization occurs in lacustrine shales in the Lower Devonian Rhynie chert, Aberdeenshire, UK, preserved by hot spring silicification. Mineralization follows a combination of first-cycle erosion of granite to yield detrital monazite grains, bioweathering of the monazite to liberate [...] Read more.
Rare earth element (REE) fluorocarbonate mineralization occurs in lacustrine shales in the Lower Devonian Rhynie chert, Aberdeenshire, UK, preserved by hot spring silicification. Mineralization follows a combination of first-cycle erosion of granite to yield detrital monazite grains, bioweathering of the monazite to liberate REEs, and interaction with fluorine-rich hot spring fluids in an alkaline sedimentary environment. The mineral composition of most of the fluorocarbonates is referable to synchysite. Mineralization occurs at the surface, and the host shales subsequently experience maximum temperatures of about 110 ℃. Most fluorocarbonate mineralization originates at much higher temperatures, but the Rhynie occurrence emphasizes that low-temperature deposits are possible when both fluorine and REEs are available from granite into the sedimentary environment. Full article
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Article
Late Devonian A-Type Granites from the Beishan, Southern Central Asia Orogenic Belt: Implications for Closure of the Paleo-Asia Ocean
Minerals 2023, 13(4), 565; https://doi.org/10.3390/min13040565 - 18 Apr 2023
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Abstract
The closing time of the Paleo-Asian Ocean (PAO) has long been in the focus of research as well as of controversial debates. The Paleozoic A-type granites distributed in the Beishan Orogenic Belt (BOB) at the southern margin of the Central Asian Orogenic Belt [...] Read more.
The closing time of the Paleo-Asian Ocean (PAO) has long been in the focus of research as well as of controversial debates. The Paleozoic A-type granites distributed in the Beishan Orogenic Belt (BOB) at the southern margin of the Central Asian Orogenic Belt (CAOB) provide pivotal clues to constrain the closure of the PAO. In this paper, the newly recognized Duhongshan A-type granites from the middle Huaniushan arc in the BOB (zircon LA-ICP-MS U-Pb ages of ca. 376–374 Ma) are thoroughly studied. The rocks have high SiO2, K2O contents with peralkaline character, and display high Zr + Nb + Ce + Y contents (354–543 ppm), 10,000 × Ga/Al (4.1–4.9), Y/Nb (3.2–5.3), Rb/Nb ratios (8.5–14.1), and a zircon saturation temperature in the range of 877–950 °C, indicative of A2-type granites affinities. The Duhongshan granites display enriched in Th and U; depleted in Ba, Sr, and Ti; with slightly positive whole-rock εNd(t) values (+1.86 to +2.21), indicating an origin related to partial melting of lower crustal material in post-collision extension settings. Combined with previous reported results, we conclude that the granitoids in the middle Huaniushan arc were mostly formed around 424–367 Ma and can be divided into two types based on petrochemistry: (a) A-type granites, which generally have high SiO2 and K2O, derived from the relatively shallow crustal source in post-collision tectonic settings; and (b) adakite and I-type granites, which display high Sr/Y ratios as well as Nb, Ta, and Ti depletion, likely generated from the melting of juvenile crust in active continental margin arcs. Integrating the previous regional investigations, we propose that the Hongliuhe–Niujuanzi–Xichangjing Ocean (HNXO) of the PAO was closed and transformed in the post-collision extensional tectonic stage during the Late Devonian and formed as post-collision magmatism, while the arc magmatism may be related to the subduction of the Liuyuan Ocean, which is located in the Southern HNXO. Full article
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Article
Mineral Characteristics and the Mineralization of Leptynite-Type Nb–Ta Ore Deposit in the Western Qilian Orogenic Belt
Minerals 2023, 13(2), 218; https://doi.org/10.3390/min13020218 - 02 Feb 2023
Viewed by 1066
Abstract
A large Nb–Ta ore deposit was found in the Yushishan leptynite in the west Qilian Orogenic Belt (QOB). Based on a field geological survey and using a Mineral Liberation Analyser (MLA, including scanning electron microscopy (SEM) and energy-dispersive spectrometer (EDS)) methods, eight Nb [...] Read more.
A large Nb–Ta ore deposit was found in the Yushishan leptynite in the west Qilian Orogenic Belt (QOB). Based on a field geological survey and using a Mineral Liberation Analyser (MLA, including scanning electron microscopy (SEM) and energy-dispersive spectrometer (EDS)) methods, eight Nb minerals (fergusonite, polycrase, columbite, Nb-rutile, aeschynite, pyrochlore, microlite, and ilmenorutile) were found to occur in the leptynite. This accounted for approximately 69% of Nb, with fergusonite, polycrase, and columbite being the dominant phases. The other 17.90% Nb as a minor element was dispersed in titanium magnetite–maghemite, and another 13.00% Nb was dispersed in gangue minerals. Nb minerals are formed mainly by two metallogenesis stages. The first stage is magmatic genesis to form four Nb minerals, euhedral-subhedral fergusonite, polycrase, pyrochlore, and microlite, which are crystallized within or between primary minerals, such as quartz and feldspar. Late alteration phenomena are locally observed. The second stage is the hydrothermal genesis of columbite, anhedral fergusonite, Nb-rutile, and aeschynite, which are dispersed in the fissures of the wall rocks as irregular veins and lump assemblages. Meanwhile, they are closely associated with metasomatic chlorite, albite, and secondary quartz. Furthermore, direct metasomatism among different Nb minerals is also found at the local scale. The Nb percentage of these two Nb mineral mineralization types is approximately equal, which reflects two main mineralizing periods. The first stage of mineralization occurred in the Neoproterozoic Era (834–790 Ma). Magmatism of this period produced early niobium and formed fergusonite, polycrase, pyrochlore, microlite, and zircon. The initial enrichment of Nb, Ta, and other rare metals occurred during this stage. The second stage of mineralization occurred in the Caledonian period (490–455 Ma). Large-scale and intense tectonic–magmatic thermal events occurred in the western part of the QOB due to the plate subduction and convergence (510–450 Ma). Hydrothermal activity in this period formed columbite, fergusonite, Nb-rutile, and aeschynite. Moreover, rare metal elements in the Nb-bearing rocks activated and migrated at short distances, forming in situ Nb–Ta-rich ore deposits. Full article
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Review

Jump to: Research

Review
A Tentative Model for the Origin of A-Type Granitoids
Minerals 2023, 13(2), 236; https://doi.org/10.3390/min13020236 - 07 Feb 2023
Cited by 2 | Viewed by 1465
Abstract
A-type granites are typically formed in stable intra-plate, back-arc or postcollisional settings and are characterized by highly ferroan and potassic major element compositions, and by strong enrichment in incompatible trace elements. Unlike I-, S- and M-type granites, where the letters denote the dominant [...] Read more.
A-type granites are typically formed in stable intra-plate, back-arc or postcollisional settings and are characterized by highly ferroan and potassic major element compositions, and by strong enrichment in incompatible trace elements. Unlike I-, S- and M-type granites, where the letters denote the dominant source material (igneous, sedimentary or mantle derived), there is no consensus on the source and processes giving rise to A-type magmas. In this contribution, a conceptual model for the origin of A-type granitoids, using the Bornholm A-type granitoid complex in southern Fennoscandia as an example, is presented. In this model, underplated mantle-derived basaltic magma may develop into intermediate and siliceous A-type magma, which is ferroan, potassic and highly enriched in incompatible trace elements, through a combination of fractional crystallization leading to cumulate formation, and partial melting and crustal assimilation, in a process akin to zone refining in metallurgy. The key factor is a relatively stable tectonic environment (postcollisional, anorogenic, or extensional), where there is little or no replenishment of more primitive basaltic magma to the system, allowing it to attain more evolved, enriched and extreme compositions. The A-type granitoids may then be viewed as a more evolved counterpart of subduction-related I-type granitoids. Full article
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Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

1. Wanyi Zhang et. al Granite Petrogenesis P-T constrained by biotites in the Western Qinling Orogen Belt, Central China


2. Jiao-Long Zhao et. al Petrogenesis and dynamic implications for the two subgroups of Paleozoic adakitic granitoids in the North Qilian orogenic belt, NW China: A review


3. Junpeng Yu et. al Study on the geological and geochemical characteristics and its significance of granulite type niobium-tantalum deposits in the middle of Altyn Tagh Tectonic Belt


4. Junpeng Yu et. al Metallogenesis of Luoda type siderite deposits in the West Qinling Orogenic Belt, China
Muhammad Saleem Mughal Petrography of mafic igneous trap and lateritic bauxite deposits: Implications for opening of Cenotethys Ocean


5. Erteng Wang et. al Closure of the Paleo-Asian Ocean: constraint from zircon U-Pb chronology and whole-rock geochemistry of granite in the northern Alxa block


6. Wanfeng Chen et. al New frontier methods in the study of granite genesis

7.Changbing Huang et. al Petrogenesis of Penglai Mesozoic granitoids: Implication for Paleo-Pacific Plate subduction

8. Åke Johansson A tentative model for the origin of A-type granitoids

9. Andrea Raucsikné Varga et.al Effects of Metasomatism on Granite-Related Mineral Systems: A Boron-Rich Open Greisen System in the Highiş Granitoids (Apuseni Mountains, Romania)

10. Yuanhao Zhao et.al Early Cenozoic fault-driven exhumation of granitoid in the southern Altun Shan: Constraints from apatite fission track ages

11. Jiyong Li et.al Fe-Mo isotope variations in granitoids: Implication for continental crust growth

12. Parnell, John et.al Low-temperature fluorocarbonate mineralization, Lower Devonian Rhynie Chert, UK

 

 

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