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Journal articles on the topic 'Magmatisme riche en K'

Author: Grafiati

Published: 8 March 2025

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1

Hernandez, Jean, Francois Dominique de Larouziere, Jean Bolze, and Pierre Bordet. "Le magmatisme neogene betico-rifain et le couloir de decrochement trans-Alboran." Bulletin de la Société Géologique de France III, no. 2 (1987): 257–67. http://dx.doi.org/10.2113/gssgfbull.iii.2.257.

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Abstract The Miocene basin evolution of southeastern Spain and eastern Morocco is linked to a "shear zone" elongated from SW across the Alboran Sea. In Spain the magmatism is mostly calc-alkaline (or K-rich calc-alkaline). Most of the products are locatred on strike-slip faults (Almeria-Cabo de Gata). Lavas of dacitic compositions are interpreted as products of crustal anatexis. During Messinian time, lamproites are erupted over an extended area. Later (Plio-Quaternary), alkali basalts are located near Cartagena. In Morocco, calc-alkaline magmatism is not as developed as in Spain; late Tortoni

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Magrina, Benoît, Michel Jébrak, and Michel Cuney. "Le magmatisme de la région de Kwyjibo, Province du Grenville (Canada) : intérêt pour les minéralisations de type fer-oxydes associées." Canadian Journal of Earth Sciences 42, no. 10 (2005): 1849–64. http://dx.doi.org/10.1139/e05-103.

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The granitic plutons located north of the Kwyjibo property in Quebec's Grenville Province are of Mesoproterozoic age and belong to the granitic Canatiche Complex . The rocks in these plutons are calc-alkalic, K-rich, and meta- to peraluminous. They belong to the magnetite series and their trace element characteristics link them to intraplate granites. They were emplaced in an anorogenic, subvolcanic environment, but they subsequently underwent significant ductile deformation. The magnetite, copper, and fluorite showings on the Kwyjibo property are polyphased and premetamorphic; their formation

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Prouteau, Gaelle, Rene C. Maury, Manuel Pubellier, Joseph Cotten, and Herve Bellon. "Le magmatisme post-collisionnel du Nord-Ouest de Borneo, produit de la fusion d'un fragment de croute oceanique ancre dans le manteau superieur." Bulletin de la Société Géologique de France 172, no. 3 (2001): 319–32. http://dx.doi.org/10.2113/172.3.319.

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Abstract Magmatic activity linked to syn- or post-collisional zones leads to the emplacement of remarkably heterogeneous rocks: calc-alkaline, high-K calc-alkaline or shoshonitic series variably contaminated by continental crust; anatectic granites and ignimbrites derived from the latter; and finally alkali potassic to ultrapotassic basalts [Harris et al., 1990; Pearce et al., 1984, 1990; Arnaud et al., 1992; Benito et al., 1999]. The main sources of these magmas are either the upper mantle (sub-oceanic or subcontinental) frequently metasomatized by hydrous fluid originating from the subducted

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4

Yuniarni, Rum. "Ciri Petrologi dan Geokimia Batuan Terobosan Gunung Sepikul, Trenggalek, Jawa Timur." Jurnal Geologi dan Sumberdaya Mineral 25, no. 2 (2024): 107–16. http://dx.doi.org/10.33332/jgsm.geologi.v25i2.742.

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Gunung Sepikul di bagian selatan Jawa Timur berkaitan dengan proses magmatisme yang berumur Miosen. Maksud penelitian ini untuk mengetahui karakteristik petrologi dan geokimia batuan beku Gunung Sepikul. Tujuannya mengungkapkan gambaran tektonik dan melengkapi data petrologi lajur magmatisme Jawa bagian selatan. Singkapannya berupa stock terdiri atas diorit dan granodiorit. Percontoh batuan dianalisis menggunakan metode petrografi, XRF dan ICP-MS. Data lapangan dan hasil analisa laboratorium berupa komposisi mineral serta geokimia batuan dapat menunjukkan proses magmatisme batuan Gunung Sepiku

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5

Dey, Sukanta, Sibani Kumari Nayak, Aniruddha Mitra, Keqing Zong, and Yongsheng Liu. "Mechanism of Paleoarchean continental crust formation as archived in granitoids from the northern part of Singhbhum Craton, eastern India." Geological Society, London, Special Publications 489, no. 1 (2020): 189–214. http://dx.doi.org/10.1144/sp489-2019-202.

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AbstractMany Paleoarchean cratons display a gradual change from early sodic tonalite–trondhjemite–granodiorite magmatism to late K-rich granitoid magmatism; the geodynamic significance of this change is debatable though. This contribution presents field, geochemical and zircon U–Pb age and Hf isotope results of four different 3.32–3.25 Ga granitoid bodies from the northern part of Singhbhum Craton to investigate their petrogenesis and role in crustal evolution. The granitoids range in composition from tonalites to trondhjemites, derived from intracrustal melting at low- to medium-pressure cond

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Larsen, Poul-Henrik, Lars Stemmerik, Troels F. D. Nielsen, and David C. Rex. "Lamprophyric dykes in Revdal, Scoresby Land, East Greenland: conflicting field observations and K-Ar age determinations." Bulletin of the Geological Society of Denmark 38 (April 25, 1990): 1–9. http://dx.doi.org/10.37570/bgsd-1990-38-01.

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Field observations on Iamprophyric dykes in Revdal, Scoresby Land, suggest a Late Permian age and the dykes would thus represent magmatism related to Permian rifting and basin formation, whereas K-Ar age determinations and chemistry suggest a Tertiary age. It is concluded that the dykes probably are Tertiary and never penetrated Upper Permian sediments due to chilling and fracturing at the base of Upper Permian water rich sediments. The dykes most likely belong to a period of alkaline magmatism that followed the onset of sea floor spreading in this part of the North Atlantic around 55 Ma ago.

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7

Widana, Kurnia Setiawan, and Bambang Priadi. "Karakteristik Unsur Jejak Dalam Diskriminasi Magmatisme Granitoid Pulau Bangka." EKSPLORIUM 36, no. 1 (2015): 1. http://dx.doi.org/10.17146/eksplorium.2015.36.1.2766.

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Geologi Pulau Bangka disusun oleh variasi granit sebagai Granitoid Klabat yang tersebar di berbagai lokasi. Unsur jejak dapat diaplikasikan dalam diskriminasi magmatisme dalam pembentukan granitoid tersebut. Tujuan penelitian ini adalah mengetahui karakteristik granitoid yang tersebar di Pulau Bangka berdasarkan geokimia unsur jejak untuk diaplikasikan dalam mempelajari magmatisme, sumber dan situasi tektoniknya.Metode analisis geokimia yang diaplikasikan dengan menggunakan Analisis Aktivasi Neutron (AAN) dan portableX-Ray Fluorescence (pXRF) untuk analisis kualitatif dan kuantitatif pada 27 s

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8

Morin, David, Réjean Hébert, and Louise Corriveau. "Mesoproterozoic deep K-magmatism recorded in a megacryst- and xenolith-bearing minette dyke, western Grenville Province." Canadian Journal of Earth Sciences 42, no. 10 (2005): 1881–906. http://dx.doi.org/10.1139/e05-083.

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The 1.07 Ga Rivard minette dyke transported thousands of exotic (xenoliths) and cogenetic (cognate nodules) clasts from deep lithospheric levels of the Grenville Province. Nodules related to the clinopyroxene- and biotite-phyric host consist of megacrystic clinopyroxene and K-feldspar and mica-rich pyroxenite. Clinopyroxene megacrysts record high-pressure and high-temperature crystallization, crystal recycling, or magma mixing, whereas Ba-rich K-feldspar megacryst possibly represent near-solidus phenocrysts crystallized from evolved K-rich magmas. Mica-pyroxenite xenoliths are interpreted as p

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Müntener, Othmar, Peter Ulmer, and Jonathan D. Blundy. "Superhydrous Arc Magmas in the Alpine Context." Elements 17, no. 1 (2021): 35–40. http://dx.doi.org/10.2138/gselements.17.1.35.

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Magmatic rocks in the Alps are scarce. What little arc magmatism there was pre-dates the Eurasia–Adria collision at 43–34 Ma but ends at 30–29 Ma. Conversely, geochemical data for magmatic rocks from the Alps resemble that of subduction-related magmatic arcs. A characteristic of Alpine magmatism is the occurrence of relatively deep (80–100 km) super-hydrous (&gt;8 wt% H2O) low-K primary magmas in the east and shoshonitic K-rich magmas in the west. These features are likely related to the absence of vigorous mantle wedge convection. Superhydrous primary magmas undergo extensive crystallizat

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Mulyaningsih, Sri, Sutikno Bronto, Arie Kusniadi, Lilis Apriyanti, L. Budiyanto, and Danis Agoes Wiloso. "The Petrology and Volcano-Stratigraphy of The Muria-Peninsula High-K Volcanic Rocks, Central Java, Indonesia." Journal of Geoscience, Engineering, Environment, and Technology 7, no. 2 (2022): 69–80. http://dx.doi.org/10.25299/jgeet.2022.7.2.9602.

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The Muria-Peninsula is a Quaternary volcano located in the northern Sunda arc. Its activity was controlled under high potassic and very high potassic magma series resulting in leucite-rich trachyte and pyroxene-rich basaltic-andesite. It is a strato-type volcano that is composed of lava, breccia, and tuff layers, and some dikes have some volcanic craters and maars varying in age and composition. The study area is covering the volcanoes of Muria, Genuk, and Patiayam. This paper aims to describe the petrology, mineralogy, and volcano-stratigraphy of the different volcanic materials. The data and

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11

Dia, Aline, Bernard Dupré, Clément Gariépy, and Claude J. Allègre. "Sm–Nd and trace-element characterization of shales from the Abitibi Belt, Labrador Trough, and Appalachian Belt: consequences for crustal evolution through time." Canadian Journal of Earth Sciences 27, no. 6 (1990): 758–66. http://dx.doi.org/10.1139/e90-077.

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Nd-isotopic compositions and Sm, Nd, Li, K, Rb, Sr, Ba, Ni, and Cr abundances are reported for 25 shale samples from the Canadian Shield (late Archean Abitibi greenstone belt and the mid-Proterozoic Labrador Trough) and from the Quebec Appalachians (lower Paleozoic Humber Zone). The chemical and isotopic characteristics of the samples are used to monitor the rate of generation and the compositional evolution of continental crust through time. The Nd crustal-residence ages record preferential time of continental growth around 2.7 and 1.7 Ga. The Nd model ages of the Appalachian shales do not re

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12

Cuney, Michel. "Felsic magmatism and uranium deposits." Bulletin de la Société Géologique de France 185, no. 2 (2014): 75–92. http://dx.doi.org/10.2113/gssgfbull.185.2.75.

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Abstract The strongly incompatible behaviour of uranium in silicate magmas results in its concentration in the most felsic melts and a prevalence of granites and rhyolites as primary U sources for the formation of U deposits. Despite its incompatible behavior, U deposits resulting directly from magmatic processes are quite rare. In most deposits, U is mobilized by hydrothermal fluids or ground water well after the emplacement of the igneous rocks. Of the broad range of granite types, only a few have U contents and physico-chemical properties that permit the crystallization of accessory mineral

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D’Eyrames, Elisabeth, Emilie Thomassot, Yumi Kitayama, Alexander Golovin, Andrey Korsakov, and Dmitri Ionov. "A mantle origin for sulfates in the unusual “salty” Udachnaya-East kimberlite from sulfur abundances, speciation and their relationship with groundmass carbonates." Bulletin de la Société géologique de France 188, no. 1-2 (2017): 6. http://dx.doi.org/10.1051/bsgf/2017007.

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The Udachnaya-East pipe in Yakutia in Siberia hosts a unique dry (serpentine-free) body of hypabyssal kimberlite (<0.64wt% H2O), associated with a less dry type of kimberlite and a serpentinized kimberlitic breccia. The dry kimberlite is anomalously rich in salts (Na2O and Cl both up to 6wt%) whereas the slightly less dry and the breccia kimberlite are salt free. Yet the Udachnaya kimberlite is a group-I kimberlite, as is the archetypical kimberlite from Kimberley, South Africa. Samples were studied from the three different types of kimberlite (dry-salty, n=8, non-salty, n=5 and breccia, n=

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14

Castor, Stephen B., and Christopher D. Henry. "Lithium-Rich Claystone in the McDermitt Caldera, Nevada, USA: Geologic, Mineralogical, and Geochemical Characteristics and Possible Origin." Minerals 10, no. 1 (2020): 68. http://dx.doi.org/10.3390/min10010068.

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Lithium deposits in tuffaceous sediments of the McDermitt caldera constitute possibly the world’s largest Li clay resource, yet their characteristics and origin are not established. The 40 × 25 km McDermitt caldera collapsed during the eruption of ~1000 km3 of a 16.4 Ma, zoned peralkaline to metaluminous tuff; minor caldera magmatism ceased by 16.1 Ma. About 200 m of sediments mostly composed of glass from regional pyroclastic eruptions accumulated in the caldera until about 15.7 Ma. Closed hydrologic system diagenesis (CHSD) altered the tuffaceous sediments to a consistent vertical mineral zo

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15

Bonazzi, Mattia, Antonio Langone, Simone Tumiati, et al. "Mantle-Derived Corundum-Bearing Felsic Dykes May Survive Only within the Lower (Refractory/Inert) Crust: Evidence from Zircon Geochemistry and Geochronology (Ivrea–Verbano Zone, Southern Alps, Italy)." Geosciences 10, no. 8 (2020): 281. http://dx.doi.org/10.3390/geosciences10080281.

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Corundum-rich (up to 55 vol.%) felsic dykes formed with albite, ±K-feldspar, ±hercynite and ±biotite-siderophyllite cut the lower crustal rocks exposed in the Ivrea–Verbano Zone (NW Italy). Zircon is an abundant accessory mineral and its investigation through laser ablation-inductively coupled plasma (multi-collector)-mass spectrometer (LA-ICP-(MC)MS) has allowed results to directly constrain the timing of emplacement, as well as petrology and geochemistry of parental melts. Zircons are characterized by very large concentration in rare earth elements (REE), Th, U, Nb and Ta, and negative Eu an

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de Lima, Jefferson Valdemiro, Ignez de Pinho Guimarães, José Victor Antunes de Amorim, Caio Cezar Garnier Brainer, Lucilene dos Santos, and Adejardo Francisco da Silva Filho. "A Review of the Mineral Chemistry and Crystallization Conditions of Ediacaran–Cambrian A-Type Granites in the Central Subprovince of the Borborema Province, Northeastern Brazil." Minerals 14, no. 10 (2024): 1022. http://dx.doi.org/10.3390/min14101022.

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Ediacaran–Cambrian magmatism in the Central Subprovince (Borborema Province, NE Brazil) generated abundant A-type granites. This study reviews published whole-rock and mineral chemistry data from thirteen Ediacaran–Cambrian A-type intrusions and a related dike swarm. It also presents new mineral chemistry and whole-rock data for one of these intrusions, along with zircon trace element data for five of the intrusions. Geochronological data from the literature indicate the formation of these A-type intrusions during a 55 Myr interval (580–525 Ma), succeeding the post-collisional high-K magmatism

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Darvishi, Esmaiel, Mahmoud Khalili, Roy Beavers, and Mohammad Sayari. "Petrology and mineral chemistry of peraluminous Marziyan granites, Sanandaj-Sirjan metamorphic belt (NW Iran)." Geologica Carpathica 66, no. 5 (2015): 361–74. http://dx.doi.org/10.1515/geoca-2015-0031.

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AbstractThe Marziyan granites are located in the north of Azna and crop out in the Sanandaj-Sirjan metamorphic belt. These rocks contain minerals such as quartz, K-feldspars, plagioclase, biotite, muscovite, garnet, tourmaline and minor sillimanite. The mineral chemistry of biotite indicates Fe-rich (siderophyllite), low TiO2, high Al2O3, and low MgO nature, suggesting considerable Al concentration in the source magma. These biotites crystallized from peraluminous S-type granite magma belonging to the ilmenite series. The white mica is rich in alumina and has muscovite composition. The peralum

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AWAD, Hamdy Ahmed Mohamed, та Aleksey Valer`evich NASTAVKIN. "Geological and petrographical studies around Um Taghir area, Сentral Eastern Desert, Egypt". NEWS of the Ural State Mining University 1, № 1 (2020): 7–25. http://dx.doi.org/10.21440/2307-2091-2020-1-7-25.

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Um Taghir area is located in the northern extreme boundary of Central Eastern Desert of Egypt at the west of Safaga City. Um Taghir is represented by island arc related rocks and late to post tectonic magmatism. The island arc related rocks are represented by metavolcaniclastic sequences and metagabrroic rocks. Metavolcanoclastic rocks are considered as the older rock units of the study are and intruded by the metagabbro. The late to post tectonic magmatism is represented by (dokhan volcanic, gabbro, tonalite-granodiorite, monzogranite, alkali feldspar granites and different types of dikes). U

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Kaur, Parminder, Suresh C. Patel, Roger H. Mitchell, et al. "Mineralogy of K-Rich Rocks from the Jharia Basin in Jharkhand: Indications for Cretaceous Lamproite Magmatism in Eastern India." Canadian Journal of Mineralogy and Petrology 61, no. 1 (2023): 105–43. http://dx.doi.org/10.3749/2200021.

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Abstract Potassic dikes of early Cretaceous age (ca. 115 Ma) are emplaced in the Gondwana sedimentary basins of the Damodar valley in eastern India. Two potassic dikes in the Jharia basin (Ena and Moonidih) are characterized by the presence of olivine macrocrysts and phenocrysts, together with microphenocrysts of olivine, phlogopite–biotite, ilmenite, and apatite. These are set in a groundmass of phlogopite, apatite, ilmenite, spinel, and K-feldspar. Microphenocrystal and groundmass Al-Na-poor diopside and Al-poor Ti-rich amphibole are present in the Ena dike, whereas rutile, pyrite, galena, Z

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Fan, Dongxu, Shucheng Tan, Xia Wang, et al. "Geochronology, Petrogenesis and Geodynamic Setting of the Kaimuqi Mafic–Ultramafic and Dioritic Intrusions in the Eastern Kunlun Orogen, NW China." Minerals 13, no. 1 (2023): 73. http://dx.doi.org/10.3390/min13010073.

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The Kaimuqi area in the Eastern Kunlun Orogen (EKO) contains many lherzolite, olivine websterite, gabbro and diorite intrusions, and new zircon U‒Pb dating, Lu‒Hf isotope and whole-rock geochemical data are presented herein to further confirm the Late Triassic mafic–ultramafic magmatism with Cu–Ni mineralization and to discuss the petrogenesis and geodynamic setting. Zircon U‒Pb dating shows that the Late Triassic ages, corresponding to 220 Ma and 222 Ma, reveal the mafic–ultramafic and dioritic magmatism in Kaimuqi, respectively. Zircon from gabbro has εHf(t) values of −3.4 to −0.2, with corr

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Baker, T. "Gold ± Copper Endowment and Deposit Diversity in the Western Tethyan Magmatic Belt, Southeast Europe: Implications for Exploration." Economic Geology 114, no. 7 (2019): 1237–50. http://dx.doi.org/10.5382/econgeo.4643.

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Abstract Major Au and Cu deposits in the Western Tethyan magmatic belt formed during two main periods of Cretaceous and Cenozoic magmatism. The Cretaceous deposits are dominantly Cu-Au porphyry, high-sulfidation epithermal, and volcanic massive sulfide deposits, whereas in the Cenozoic Cu is significant only in porphyry systems. However, the Cenozoic contains approximately three times greater total Au endowment (for Au deposits >0.5 million ounces), and also has a greater deposit diversity, including porphyry Au-Cu and Au-only deposits, high-, intermediate-, and low-sulfidation epithermal A

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Groves, David I., Liang Zhang, and M. Santosh. "Subduction, mantle metasomatism, and gold: A dynamic and genetic conjunction." GSA Bulletin 132, no. 7-8 (2019): 1419–26. http://dx.doi.org/10.1130/b35379.1.

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Abstract Global gold deposit classes are enigmatic in relation to first-order tectonic scale, leading to controversial genetic models and exploration strategies. Traditionally, hydrothermal gold deposits that formed through transport and deposition from auriferous ore fluids are grouped into specific deposit types such as porphyry, skarn, high- and low-sulfidation–type epithermal, gold-rich volcanogenic massive sulfide (VMS), Carlin-type, orogenic, and iron-oxide copper-gold (IOCG), and intrusion-related gold deposits (IRGDs). District-scale mineral system approaches propose interrelated group

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Limtrakun, P., Khin Zaw, C. G. Ryan, and T. P. Mernagh. "Formation of the Denchai gem sapphires, northern Thailand: evidence from mineral chemistry and fluid/melt inclusion characteristics." Mineralogical Magazine 65, no. 6 (2001): 725–35. http://dx.doi.org/10.1180/0026461016560004.

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AbstractThe Denchai gem sapphire deposits in Phrae Province, northern Thailand are closely associated with late Cenozoic alkaline basaltic rocks. The sapphires occur in alluvial placer deposits in palaeo-channels at shallow depths. Electron microprobe analysis of minor and trace element contents (Fe, Ti, Cr, Ga and V) of the sapphires indicate the following oxide abundances: Fe2O3 (0.32–1.98 wt.%), TiO2 (0.01–0.23 wt.%), Cr2O3 (<0.01 wt.%), Ga2O3 (0.01–0.03 wt.%) and V2O5 (<0.03 wt.%). Optical studies of sapphires revealed three types of primary fluid/melt inclusions. CO2-rich inclusions

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Kaur, Gurmeet, Roger H. Mitchell, and Suhel Ahmed. "Mineralogy of the Vattikod lamproite dykes, Ramadugu lamproite field, Nalgonda District, Telangana: A possible expression of ancient subduction-related alkaline magmatism along Eastern Ghats Mobile Belt, India." Mineralogical Magazine 82, no. 1 (2018): 35–58. http://dx.doi.org/10.1180/minmag.2017.081.045.

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ABSTRACTThe mineralogy of nine recently discovered dykes (VL1:VL8 and VL10) in the vicinity of Vattikod village, Nalgonda district in Telangana State is described. The mineral assemblage present and their compositions are comparable to those of bona fide lamproites in terms of the presence of phlogopite (Ti-rich, Al-poor phlogopite and tetraferriphlogopite); amphiboles (potassic-arfvedsonite, potassic-richterite, potassic-ferro-richterite, potassic-katophorite, Ti-rich potassic-katophorite, Ti-rich potassic-magnesio-katophorite); Al-poor clinopyroxenes; feldspars (K-feldspar, Ba-K-feldspar and

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MCCARRON, JOE J., and IAN L. MILLAR. "The age and stratigraphy of fore-arc magmatism on Alexander Island, Antarctica." Geological Magazine 134, no. 4 (1997): 507–22. http://dx.doi.org/10.1017/s0016756897007437.

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Fore-arc magmatic sequences associated with high Mg number andesite lavas unconformably overlie LeMay Group accretionary complex in Alexander Island. High-resolution 40Ar/39Ar, U–Pb zircon, fission track and K–Ar ages demonstrate that subduction-related fore-arc magmatism migrated northwards along the length of Alexander Island between c. 80 Ma and c. 46 Ma. The magmatic rocks represent a third of the western margin of the Antarctic Peninsula magmatic arc and are critical to the understanding of the final phase of subduction along the southern Antarctic Peninsula margin. The onset of late Cret

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BUZZI, L., L. GAGGERO, L. GROZDANOV, S. YANEV, and F. SLEJKO. "High-Mg potassic rocks in the Balkan segment of the Variscan belt (Bulgaria): implications for the genesis of orogenic lamproite magmas." Geological Magazine 147, no. 3 (2009): 434–50. http://dx.doi.org/10.1017/s0016756809990550.

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AbstractUltrapotassic plutons from several domains of the Variscan orogenic belt have been in turn interpreted as syn- to post-orogenic due to their age spread, but assessment of their geodynamic setting and source regions is still open to interpretation. In the Svoge region (Bulgaria), at the southern margin of the Balkan orogen, peralkalic plutons are hosted within Ordovician pelites. The main intrusion, with lamproitic affinity, which hosts monzodiorite xenoliths and a polyphase syenite suite, was emplaced at a shallow level.40Ar–39Ar dating by step-heating of amphibole and biotite yielded

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AGHAZADEH, MEHRAJ, ANTONIO CASTRO, ZAHRA BADRZADEH, and KATHARINA VOGT. "Post-collisional polycyclic plutonism from the Zagros hinterland: the Shaivar Dagh plutonic complex, Alborz belt, Iran." Geological Magazine 148, no. 5-6 (2011): 980–1008. http://dx.doi.org/10.1017/s0016756811000380.

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AbstractThe petrological and geochronological study of the Cenozoic Shaivar Dagh composite intrusion in the Alborz Mountain belt (NW Iran) reveals important clues to decipher complex relations between magmatic and tectonic processes in the central sectors of the Tethyan (Alpine–Himalayan) orogenic belt. This pluton is formed by intrusion at different times of two main magmatic cycles. The older (Cycle 1) is formed by calc-alkaline silicic rocks, which range in composition from diorites to granodiorites and biotite granites, with abundant mafic microgranular enclaves. The younger cycle (Cycle 2

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Leite, Renato J., Valdecir A. Janasi, and Lucelene Martins. "Contamination in mafic mineral-rich calc-alkaline granites: a geochemical and Sr-Nd isotope study of the Neoproterozoic Piedade Granite, SE Brazil." Anais da Academia Brasileira de Ciências 78, no. 2 (2006): 345–71. http://dx.doi.org/10.1590/s0001-37652006000200013.

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The Piedade Granite (~600 Ma) was emplaced shortly after the main phase of granite magmatism in the Agudos Grandes batholith, Apiaí-Guaxupé Terrane, SE Brazil. Its main units are: mafic mineral-rich porphyritic granites forming the border (peraluminous muscovite-biotite granodiorite-monzogranite MBmg unit) and core (metaluminous titanite-bearing biotite monzogranite BmgT unit) and felsic pink inequigranular granite (Bmg unit) between them. Bmg has high LaN/YbN (up to 100), Th/U (>10) and low Rb, Nb and Ta, and can be a crustal melt derived from deep-seated sources with residual garnet and b

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Abdel-Rahman, Abdel-Fattah M. "Mineralogy of the Neoproterozoic epidote-bearing TTG suite, Mons Claudianus batholith (Egypt) and implications for synorogenic magmatism." Mineralogical Magazine 80, no. 7 (2016): 1291–314. http://dx.doi.org/10.1180/minmag.2016.080.132.

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AbstractThe Neoproterozoic, epidote-bearing Mons Claudianus Batholith (MCB), Egypt, consists of tonalite-trondhjemite-granodiorite (TTG) lithologies, containing variable contents of quartz, feldspars, amphiboles, biotite, and magmatic epidote, with accessory titanite, zircon, allanite, apatite, opaque magnetite and ilmenite. Plagioclase varies from An49 to An19, and K-feldspars possess near end-member compositions (Or97 to Or91). Amphiboles are calcic (Ca = 1.88–1.92 atoms per formula unit (apfu)), Al-rich (average AlT = 1.84 apfu), having an average Fe/(Fe + Mg) ratio of 0.50, and are edenite

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Göncüoğlu, M. C., A. Günal-Türkmenoğlu, Ö. Bozkaya, Ö. Ünlüce-Yücel, C. Okuyucu, and İ. Ö. Yilmaz. "Geological features and geochemical characteristics of Late Devonian–Early Carboniferous K-bentonites from northwestern Turkey." Clay Minerals 51, no. 4 (2016): 539–62. http://dx.doi.org/10.1180/claymin.2016.051.4.02.

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AbstractNewly discovered K-bentonite beds, interstratified with limestones/dolomitic limestones of the Upper Devonian–Lower Carboniferous Yılanlı Formation, are exposed in the northwestern Black Sea region of Turkey, around Zonguldak and Bartın. K-bentonite samples collected from four different locations: the Gavurpınarı and Yılanlı Burnu quarries from the Bartın area, the Çimşir Çukurları quarry from the Şapça area, and the Güdüllü and Gökgöl highway tunnel section near Zonguldak city were investigated using optical microscopy, X-ray diffraction and inductively coupled plasma mass spectrometr

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FEELEY, T. C., M. A. COSCA, and C. R. LINDSAY. "Petrogenesis and Implications of Calc-Alkaline Cryptic Hybrid Magmas from Washburn Volcano, Absaroka Volcanic Province, USA." Journal of Petrology 43, no. 4 (2002): 663–703. http://dx.doi.org/10.1093/petrology/43.4.663.

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Abstract The petrogenesis of calc-alkaline magmatism in the Eocene Absaroka Volcanic Province (AVP) is investigated at Washburn volcano, a major eruptive center in the low-K western belt of the AVP. New 40Ar/39Ar age determinations indicate that magmatism at the volcano commenced as early as 55 Ma and continued until at least 52 Ma. Although mineral and whole-rock compositional data reflect near equilibrium crystallization of modal phenocrysts, petrogenetic modeling demonstrates that intermediate composition magmas are hybrids formed by mixing variably fractionated and contaminated mantle-deri

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Caroff, Martial, Hervé Bellon, Louis Chauris, et al. "Magmatisme fissural triasico-liasique dans l'ouest du Massif armoricain (France): pétrologie, géochimie, âge, et modalités de la mise en place." Canadian Journal of Earth Sciences 32, no. 11 (1995): 1921–36. http://dx.doi.org/10.1139/e95-147.

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The dolerite dykes at the western end of Britanny (France), which is located on the North Atlantic margin, were emplaced in a NW–SE field of faults at the Trias–Lias time limit, between 210 and 195 Ma. These rocks are quartz tholeiites enriched in TiO2, with a trace element composition close to that of the Deccan basalts. The initial concentrations of Ba, K, and Rb, though slightly modified by the alteration, and of Nb seem to have been affected by crustal contamination during the magma transfer. These dykes are comparable, in age and composition, to the tholeiitic dykes exposed in the Iberian

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Van Rythoven, Adrian D., Daniel J. Schulze, and Donald W. Davis. "Ultramafic xenoliths from the 1.15 Ga Certac kimberlite, eastern Superior Craton." Canadian Mineralogist 58, no. 2 (2020): 267–86. http://dx.doi.org/10.3749/canmin.1900064.

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ABSTRACT Xenoliths and xenocrysts of mantle material from kimberlite dikes located underground at the Certac Au mine, Québec, in the eastern Superior Craton, were studied in terms of the major element composition of their constituent minerals. The kimberlite was dated at 1151 ± 46 Ma by the U-Pb perovskite method. This suite thus provides a rare glimpse into the Mesoproterozoic mantle of the Superior Craton. Two parageneses of mantle material unrelated to the kimberlite magmatism occur: (1) an olivine + ilmenite ± magnetite association characterized by relatively Fe-rich olivine (Mg# = 0.68–0.

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Clarke, D. Barrie, Andrew S. Henry, and Mike A. Hamilton. "Composition, age, and origin of granitoid rocks in the Davin Lake area, Rottenstone Domain, Trans-Hudson Orogen, northern Saskatchewan." Canadian Journal of Earth Sciences 42, no. 4 (2005): 599–633. http://dx.doi.org/10.1139/e04-067.

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The Rottenstone Domain of the Trans-Hudson orogen is a 25-km-wide graniticmigmatitic belt lying between the La Ronge volcanicplutonic island arc (18901830 Ma) to the southeast and the ensialic Wathaman Batholith (1855 Ma) to the northwest. The Rottenstone Domain consists of three lithotectonic belts parallel to the orogen: (i) southeast gently folded migmatized quartzo-feldspathic metasedimentary and mafic metavolcanic rocks intruded by small concordant and discordant white tonalitemonzogranite bodies; (ii) central intensely folded and migmatized metasedimentary rocks and minor metavol

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Ece, O. I., and Z. E. Nakagawa. "Alteration of volcanic rocks and genesis of kaolin deposits in the Şile Region, northern İstanbul, Turkey. Part II: differential mobility of elements." Clay Minerals 38, no. 4 (2003): 529–50. http://dx.doi.org/10.1180/0009855033840113.

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AbstractIn the area of S° ile, NW Turkey, Upper Cretaceous calc-alkaline volcanic rocks with compositions ranging from andesite to rhyolite have been recognized. The most widespread rocks of the suite are andesites, which can be grouped into altered and fresh. The oldest altered andesites are the parent rocks for the kaolin deposits of the study area. The Upper Cretaceous volcanic suite consists of spilite, basalt, andesite, trachyandesite, trachyandesitic and hyaloandesitic dacite, rhyolite lavas, tuffs and agglomerates. The highly altered andesites are composed of plagioclase, pyroxene, horn

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Golovin, Alexander V., Alexey A. Tarasov, and Elena V. Agasheva. "Mineral Assemblage of Olivine-Hosted Melt Inclusions in a Mantle Xenolith from the V. Grib Kimberlite Pipe: Direct Evidence for the Presence of an Alkali-Rich Carbonate Melt in the Mantle Beneath the Baltic Super-Craton." Minerals 13, no. 5 (2023): 645. http://dx.doi.org/10.3390/min13050645.

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This report deals with the first mineralogical examination of secondary crystallized melt inclusions (CMIs) in healed cracks within olivine in a mantle peridotite xenolith from the V. Grib kimberlite pipe (Arkhangelsk diamondiferous province). In contrast to micro/nano-inclusions in diamonds, the studied CMIs are quite large (up to 50 µm), so that the mineral composition of the CMIs can be determined via conventional analytical approaches, e.g., Raman spectroscopy and scanning electron microscopy. Garnet peridotite is a coarse-grained mantle rock that equilibrates at 3.3 GPa and 750 °C (corres

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Davis, Alicé S., Leda-Beth G. Pickthorn, Tracy L. Valuer, and Michael S. Marlow. "Petrology and age of volcanic-arc rocks from the continental margin of the Bering Sea: implications for Early Eocene relocation of plate boundaries." Canadian Journal of Earth Sciences 26, no. 7 (1989): 1474–90. http://dx.doi.org/10.1139/e89-125.

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Eocene volcanic flow and dike rocks from the Beringian margin have arc characteristics, implying a convergent history for this region during the early Tertiary. The extrusive rocks are basalt, basaltic andesite, andesite, and minor dacite and rhyolite. The intrusive sample is from a quartz diorite dike intruding serpentinized peridotite. Major-element oxide contents, particularly FeO*/MgO versus SiO2, identify both tholeiitic and calc-alkalic basalt; more silicic lavas have calc-alkalic affinities. Consistent with volcanic-arc compositions, spidergrams show pronounced Nb–Ta depletion and alkal

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Wu, Bin, Christophe Bonnetti, Yue Liu, et al. "Uraninite from the Guangshigou Pegmatite-Type Uranium Deposit in the North Qinling Orogen, Central China: Its Occurrence, Alteration and Implications for Post-Caledonian Uranium Circulation." Minerals 11, no. 7 (2021): 729. http://dx.doi.org/10.3390/min11070729.

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The Guangshigou deposit is the largest pegmatite-type uranium deposit in the Shangdan domain of the North Qinling Orogenic Belt, which is characterized by the enrichment of uraninite hosted in biotite granitic pegmatites. At Guangshigou, uraninite commonly occurs as mineral inclusions in quartz, K-feldspar and biotite or in interstices of these rock-forming minerals with magmatic characteristics (e.g., U/Th < 100, high ThO2, Y2O3 and REE2O3 contents and low concentrations of CaO, FeO and SiO2). It crystallized at 407.6 ± 2.9 Ma from fractionated calc-alkaline high-K pegmatitic melts under c

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Kholodnov, V. V., E. S. Shagalov, G. A. Kallistov, G. Yu Shardakova, D. N. Salikhov, and E. V. Konovalova. "The Akhunovo–Petropavlovsk Granitoid Area as a Continental-Margin Center of the Long-Term Mantle–Crust Interaction: The Role of Subductional and Rift–Plume Sources." Russian Geology and Geophysics 62, no. 6 (2021): 648–65. http://dx.doi.org/10.2113/rgg20194121.

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Abstract —The Akhunovo–Petropavlovsk area of the late Paleozoic granite magmatism is located in the northeast of the Magnitogorsk megazone (MMZ) in the South Urals. It is a series of successively intruded rocks (Petropavlovsk, Akhunovo, Karagai, and Uiskii Bor intrusions) differing not only in composition, the depth of formation, and ore content but also in the relationship with magmatic and fluid sources and in magma generation mechanisms. This area differs significantly in the number and composition of intrusive complexes from the igneous rocks and ore associations in the central and western

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Dey, Sukanta, and Jean-François Moyen. "Archean granitoids of India: windows into early Earth tectonics – an introduction." Geological Society, London, Special Publications 489, no. 1 (2020): 1–13. http://dx.doi.org/10.1144/sp489-2020-155.

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AbstractGranitoids form the dominant component of Archean cratons. They are generated by partial melting of diverse crustal and mantle sources and subsequent differentiation of the primary magmas, and are formed through a variety of geodynamic processes. Granitoids, therefore, are important archives for early Earth lithospheric evolution. Peninsular India comprises five cratonic blocks bordered by mobile belts. The cratons that stabilized during the Paleoarchean–Mesoarchean (Singhbhum and Western Dharwar) recorded mostly diapirism or sagduction tectonics. Conversely, cratons that stabilized du

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Lin, Hao, Zuochen Li, Xianzhi Pei, et al. "Investigating the Orogenic Evolution of the Wushan–Shangdan Ocean in the Qinling–Qilian Conjunction Zone: Insights from the Early Devonian Tailu Pluton." Minerals 14, no. 9 (2024): 910. http://dx.doi.org/10.3390/min14090910.

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The main ocean–continent transformation stage of the Qinling and Qilian conjunction zone happened in the Early Paleozoic with the occurrence of a lot of subduction–collision–related magmatic rocks. However, there is still considerable controversy over the duration of the subduction–collision orogeny process of the Proto-Tethys Ocean, here termed as the Wushan–Shangdan Ocean. We provide geochronological, geochemical, and Lu-Hf isotopic data for typical Early Devonian igneous rocks there, named Tailu pluton. The Tailu pluton at 410 Ma comprised K-rich, calc-alkaline, metaluminous A-type granite

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42

Upton, B. G. J., A. A. Finch, and E. Słaby. "Megacrysts and salic xenoliths in Scottish alkali basalts: derivatives of deep crustal intrusions and small-melt fractions from the upper mantle." Mineralogical Magazine 73, no. 6 (2009): 943–56. http://dx.doi.org/10.1180/minmag.2009.073.6.943.

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AbstractCa-poor and typically Na-rich feldspar megacrysts are common associates of spinel lherzolitic and pyroxenitic xenoliths in Scottish alkalic basalts. Associated megacrysts and composite megacrysts and salic xenoliths include apatite, magnetite, zircon, biotite, Fe-rich pyroxene(s) and corundum. The salic xenoliths and related megacrysts are referred to collectively as the ‘anorthoclasite suite': the majority of the samples are inferred to derive from the disaggregation of coarse-grained, typically Na-rich, syenitic protoliths at depth. Rare occurrences of euhedral anorthoclase megacryst

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Damogalad, Yustina, Aang Panji Permana, Ronal Hutagalung, and Intan Noviantari Manyoe. "Karakteristik Batuan Dasar Formasi Gabro Daerah Keramat Kabupaten Boalemo." JRST (Jurnal Riset Sains dan Teknologi) 8, no. 1 (2024): 81. http://dx.doi.org/10.30595/jrst.v8i1.17323.

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Secara administratif wilayah penelitian terletak di Desa Keramat dan sekitarnya, Kabupaten Boalemo, Provinsi Gorontalo. Daerah penelitian tersususun oleh batuan terobosan dari formasi Batuan Gabro (Teog), Formasi Batuan Granodiorit Bumbulan (Tpb) dan Formasi Aluvium (Qal). Kondisi geologi daerah penelitian sangat kompleks sehingga menarik diteliti karena belum pernah dilakukan penelitian secara detail. Tujuan penelitian yang akan dicapai adalah mengetahui karakteristik mineralogi dan tekstur serta proses terbentuknya batuan dasar berdasarkan data pemetaan geologi dan data petrografi. Metode pe

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El-Wardany, Refaey M., Jiangang Jiao, Basem Zoheir, Mustafa Kumral, Mustafa Kaya, and Amr Abdelnasser. "Post-Subduction Granite Magmatism and Gold-Sulfide Mineralization in the Abu Zawal (Fatira) Area, Eastern Desert, Egypt." Minerals 13, no. 4 (2023): 489. http://dx.doi.org/10.3390/min13040489.

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Gold-sulfide mineralization in the Abu Zawal (Fatira) mine area, North Eastern Desert of Egypt, is related to porphyritic felsite dikes and elongate silicification zones in granitic rocks. These felsite dikes and the host granitic rocks exhibit major and trace element geochemical features typical of calc-alkaline and metaluminous I-type granites, likely originated in a late-orogenic setting. Their geochemical characteristics along with their fractionated LREE relative to HREE patterns imply either formation in a subduction-related environment or generation from subduction-modified source mater

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Chambers, Larry W. "N. Keating, J. Fast, J. Frederick, K. Cranswick, and C. Perrier Eldercare in Canada: Context, Content and Consequences. Ottawa, ON: Statistics Canada. Ministry of Industry, 1999. Catalogue no. 89-570-XPE." Canadian Journal on Aging / La Revue canadienne du vieillissement 20, no. 3 (2001): 430–31. http://dx.doi.org/10.1017/s0714980800012885.

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RÉSUMÉDans leur livre, Eldercare in Canada: Context, content and consequences, Keating et al. concluent que les Canadiens accordent une quantité importante de soins à leurs aîné(e)s. Bien qu'ils soient parfois structurés et subventionnés, les soins sont plutôt officieux et non subventionnés. Le livre décrit les caractéristiques du soignant et du soigné, le contexte de la prestation des soins ainsi que les coûts sociaux, psychosociaux, physiques et économiques des soins. Il relève les questions de politiques que les auteurs estiment aptes à maintenir la quantité et la qualité des soins actuelle

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46

Nikolenko, Evgeny I., Konstantin V. Lobov, Alexey M. Agashev, et al. "40Ar/39Ar Geochronology and New Mineralogical and Geochemical Data from Lamprophyres of Chompolo Field (South Yakutia, Russia)." Minerals 10, no. 10 (2020): 886. http://dx.doi.org/10.3390/min10100886.

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The alkaline igneous rocks of the Chompolo field (Aldan shield, Siberian craton), previously defined as kimberlites or lamproites, are more correctly classified as low-Ti lamprophyres. The emplacement age of the Ogonek pipe (137.8 ± 1.2 Ma) and the Aldanskaya dike (157.0 ± 1.6 Ma) was obtained using 40Ar/39Ar K-richterite dating. The Chompolo rocks contain abundant xenocrysts of mantle minerals (chromium-rich pyropic garnets, Cr-diopsides, spinels, etc.). The composition of the mantle xenocrysts indicates the predominance of spinel and garnet–spinel lherzolites, while the presence of garnet lh

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47

Clément, Jean-Philippe, Martial Caroff, Christophe Hémond, et al. "Pleistocene magmatism in a lithospheric transition area: petrogenesis of alkaline and peralkaline lavas from the BaringoBogoria Basin, central Kenya Rift." Canadian Journal of Earth Sciences 40, no. 9 (2003): 1239–57. http://dx.doi.org/10.1139/e03-046.

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New petrological, geochronological, and geochemical data on basalts, mugearites, peralkaline trachytes, and phonolites from the BaringoBogoria Basin, central Kenya Rift, are presented. KAr dating indicates that the volcanic rocks were emplaced between 894 ± 13 and 92 ± 5 ka. 87Sr/86Sr ranges from 0.70304 to 0.70692, 143Nd/144Nd from 0.51237 to 0.51295, 206Pb/204Pb from 18.4 to 19.8, 207Pb/204Pb from 15.46 to 15.70, and 208Pb/204Pb from 38.2 to 40.5. Despite a rather restricted sampling area and a relatively short time span ([Formula: see text]820 ka), the mineralogical and geochemical variat

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48

Song, Dongfang, Wenjiao Xiao, Brian F. Windley, and Chunming Han. "Carboniferous to Early Triassic magmatism and accretion in Alxa (NW China): implications for accretionary orogenesis of the southern Altaids." Journal of the Geological Society 177, no. 5 (2020): 997–1012. http://dx.doi.org/10.1144/jgs2020-046.

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Alxa occupies a crucial position between the Tianshan–Beishan orogen to the west and the Solonker suture to the east and is important in our understanding of the accretionary orogenesis of the southern Altaids. To unravel the tectonic history of the Alxa region, we undertook an integrated study of the field geology, geochemistry and geochronology of magmatic rocks and an accretionary complex. Six granites and one rhyolite from the Zhusileng–Hangwula arc show a peraluminous, high-K calc-alkaline composition and one gabbro is tholeiitic. They show patterns rich in incompatible elements and negat

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Speziale, Sergio, Francesca Castorina, Paolo Censi, Celso de Barros Gomes, Leila Soares Marques, and Piero Comin-Chiaramonti. "Carbonatites from the southern Brazilian Platform: A review. II: Isotopic evidences." Open Geosciences 12, no. 1 (2020): 678–702. http://dx.doi.org/10.1515/geo-2020-0032.

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AbstractEarly and Late Cretaceous alkaline and alkaline–carbonatitic complexes from southern Brazil are located along the main tectonic lineaments of the South America Platform. Calcium-, magnesium-, and ferrocarbonatites are well represented and frequently associated even in the same complex. Primary carbonates present significant variations in C–O isotopic compositions, which are mainly due to isotope exchange with H2O–CO2-rich hydrothermal fluids, whereas fractional crystallization or liquid immiscibility probably affects the δ18O and δ13C values by no more than 2δ‰. Our isotope exchange mo

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Huang, Gang, Liang-Liang Zhuang, Ya-Qi Yang, Li-Dan Tian, Wei Wu, and Jin-Hong Liu. "Petrogenesis and Tectonic Setting of the Madeng Dacite, SW Sanjiang Indosinian Orogen: Evidence from Zircon U-Pb-Hf Isotopes, and Whole-Rock Geochemistry and Sr-Nd Isotopes." Minerals 12, no. 3 (2022): 388. http://dx.doi.org/10.3390/min12030388.

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The Sanjiang Indosinian orogen, located in the eastern part of the Paleo-Tethys tectonic domain, is a critical region to study the Paleo-Tethyan Ocean evolution. Middle Permian–Late Triassic magmatic rocks are widespread in the Deqin–Weixi–Madeng area of southwestern (SW) Sanjiang Indosinian orogen, yet their petrogenesis and tectonic setting remain disputed. In this study, LA-ICP-MS zircon U-Pb age and Hf isotopes, and whole-rock elemental and Sr-Nd isotope geochemistry of Madeng dacite were studied. The Madeng dacite was dated at ca. 241.7 and 243.4 Ma. The samples had high Al2O3 (12.91 to 1

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