The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In-situ SIMS analyses of O and U–Pb isotopes as well as LA-(MC)-ICPMS analyses of trace elements, U–Pb, and Lu–Hf isotopes were carried out for zircon from a quartz vein and its host UHP eclogite in the Dabie orogen. The results are integrated to decipher the effect of aqueous fluid on the new growth of metamorphic zircon and on the recrystallization of protolith zircon during continental subduction-zone...
Spatial variations in whole-rock Sr–Nd–Pb isotopic compositions were investigated for Early Cretaceous mafic igneous rocks from western Shandong in the southeastern edge of the North China Block (NCB). The results are used to constrain the spatial extent of the influence of the deeply subducted South China Block (SCB) on the collided NCB. Five localities of mafic rocks were analyzed in this study,...
In-situ electron microprobe (EMP) U–Th–Pb monazite-, sensitive high-resolution ion microprobe (SHRIMP) zircon analyses, metamorphic phase equilibrium (Domino/Theriak)- and geothermobarometric calculations are performed on kyanite/sillimanite-bearing garnet biotite gneisses forming part of the dominant rock association in the Xitieshan ultra-high pressure metamorphic belt, north Qaidam, western China...
The Neoproterozoic Haizhou Group crops out sporadically in the Sulu orogen in east-central China. It is divided into the Jinping and Yuntai formations and consists of quartzite, quartz schist, marble and graphite- and apatite-bearing sequences. Major and trace element data for quartz schist from the two formations indicate that these rocks have a greywacke protolith and have been deposited during...
Felsic veins within the Xitieshan UHP eclogite in North Qaidam, NW China vary from 1cm or less to several decimetres in width, exhibiting coarse granular in texture and heterogeneous distribution in mineral assemblages. They encircle or cut the deformed sub-lentoid eclogite body. Some fine veins extended into and ended in the eclogite, without visible link to their country rocks. They consist mainly...
The South Tianshan Collisional Belt (STCB), formed by the collision between the Tarim and Central Tianshan blocks, is pivotal for understanding the complex and prolonged tectonic evolution of the Central Asian Orogenic Belt (CAOB). The Chuanwulu complex is located in the eastern part of the STCB, Xinjiang province, NW China. It consists of a gabbro–diorite unit (unit I) and a monzonite–syenite unit...
The Tongshi intrusive complex, located within the western Shandong Province (Luxi Block) in the eastern North China Craton, comprises high-K calc-alkaline series (fine-grained quartz monzonite and porphyritic quartz monzonite) and shoshonitic series (coarse- to fine-grained porphyritic syenites). Here we report comprehensive data on petrology, geochemistry, Sr–Nd–Pb isotopes and zircon U–Pb and Hf...
The Udachnaya East kimberlite sampled garnet peridotite xenoliths from a pressure range of 1.2 to 7.1GPa in the underlying Siberian cratonic lithosphere. Samples derived from <5.2GPa lie close to a typical cratonic geotherm of 40mWm −2 , whereas more deeply derived samples have temperatures ≥100°C above this geotherm. Minor and trace element compositions of garnet and clinopyroxene indicate...
In northern Victoria Land (Antarctica) the Lanterman-Mariner suture separates the inboard Wilson Terrane from the outboard Bowers and Robertson Bay terranes. This boundary is characterized by the presence of discontinuous bodies of mafic to ultramafic rocks with a metamorphic grade ranging from medium-P amphibolite facies (Mountaineer Range) to ultrahigh-P eclogite facies (Lanterman Range). The Dessent...
Metasiliciclastic rocks predominate in the lower units of the Palaeo-Mesoproterozoic Espinhaço Supergroup, in the southern Serra do Espinhaço, Minas Gerais, Brazil. The lower units also comprise rocks with locally preserved igneous fabrics, but which have very unusual chemistries. These rocks, collectively known as hematitic phyllite, are characterised by abundant fine-grained muscovite, i.e. sericite,...
The Mayile ophiolitic mélange (MOM) is located in the southwestern part of the West Junggar (NW China) and forms part of the Southern Altaids. The MOM comprises ultramafic rocks, gabbro, pillow and massive lavas, abyssal radiolarian cherts and volcaniclastic rocks. Zircons with magmatic crystallization features including oscillatory zoning and high Th/U values from the isotropic gabbro within the...
Granitoid clasts in pyroclastic deposits of the 0.7ka (Kaharoa) eruption from the intra-caldera Tarawera volcano of the Okataina Volcanic Centre (OVC), New Zealand, provide an insight to the plutonic processes beneath one of the most productive Quaternary rhyolite centers on Earth. SIMS U–Th data for 79 granitoid zircon crystals from six clasts reveal a unimodal age spectrum yielding a weighted average...
We report results of petrologic, geochronological and geochemical investigation of the Late Carboniferous diorites, granodiorites, amphibole (Am)-bearing granites, and associated dioritic and monzonitic enclaves and mafic and granitic dikes in the Keramay area, of the western Junggar region of Central Asian Orogenic Belt (CAOB). Zircon U–Pb dating suggests that they were generated in the Late Carboniferous...
We provide 2D thermomechanical numerical models to constrain the subduction process of narrow (~ 600km wide) oceanic basins resulting in formation and exhumation of serpentinite-bearing high-pressure (HP) and ultrahigh-pressure (UHP) complexes presently exposed as dismembered massifs in orogenic belts. We simulated subduction of “heterogeneous” (i.e. non layered) oceanic lithosphere testing different...
Textural and compositional features of plagioclase phenocrysts of the 1991 eruption lavas at Avachinsky Volcano (Kamchatka, Russia) were used to investigate the feeding system processes. Volcanics are porphyritic basaltic andesites and andesites with low-K affinity. A fractionation modeling for both major and trace elements was performed to justify the development of these evolved compositions. The...
A diverse suite of intermediate to felsic rocks from the Baimaxueshan pluton within the Sanjiang Orogen, SW China, documents the tectonomagmatic history of closure of the eastern Paleo-Tethys and associated arc accretion onto the margin of Asia. The pluton consists mainly of diorite, tonalite and granodiorite, and contains mafic magmatic enclaves (MMEs). SHRIMP U–Pb analyses on zircons from the MMEs...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.