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Mesozoic granitoid rocks represent a volumetrically component of the Northeastern (NE) China and preserve useful information about the tectonomagmatic history of this region. The Sankuanggou intrusion associated with skarn Fe-Cu deposit in the Duobaoshan ore field within NE China primarily consists of granodiorite with minor alkali-feldspar granite and diorite, which intrudes the Ordovician Duobaoshan...
Mt. Takahe is a large, late Quaternary trachyte shield volcano that rises through 2000+m of the West Antarctic ice sheet. It is composed mostly of ne-trachyte, hy-ol-trachyte, and qz-trachyte flows, with subordinate basanite, intermediate rocks, and pantellerites.All rock types can be adequately modeled by fractional crystallization of basanite - the only basaltic rock exposed here. The ne-trachytes...
Adakitic intrusions are supposed to have a close genetic and spatial relationship to porphyry Cu deposits. However, the genesis of adakitic intrusions is still under dispute. Here, we describe newly discovered intrusive complex rocks, which are composed of ore-bearing, layered magnetite-bearing gabbroic and adakitic rocks in Jiamate, East Junggar, NW China. These Jiamate Complex intrusions have diagnostic...
The ~2.06Ga mafic-ultramafic Kevitsa intrusion is located in the Central Lapland greenstone belt. The lower ultramafic part of the intrusion hosts a large disseminated Ni-Cu-(PGE) sulfide deposit with Ni tenors ranging widely from <4wt% (uneconomic false ore and contact mineralization) to 4–7wt% (regular ore) and up to 40wt% (Ni-PGE ore). The stratigraphy of the ultramafic cumulates is divided...
Migmatites provide a record of melt formation and crustal rheology. In this study we present zircon U-Pb ages and geochemical composition of migmatites from the Foping dome and granites from the Wulong pluton. U-Pb results from migmatite zircons indicate two episodes of partial melting. Rim domains from a leucosome in the Longcaoping area yield an age of ca. 209Ma. Migmatites collected from the Foping...
This study combines whole rock trace and major element geochemistry, and stable isotope (δD and δ18O) analyses with petrographic observations to deduce the origin and tectonic setting of serpentinization of ultramafic blocks from the exhumed HP/LT Aegean subduction complex on Syros, Greece. Samples are completely serpentinized and are characterized by mineral assemblages that consist of variable amounts...
The Qiman Tagh of the East Kunlun Orogen, NW China, lies within the Tethysides and hosts a large W–Sn belt associated with the Bashierxi monzogranite. To constrain the origin of the granitic magmatism and its relationship with W–Sn mineralization and the tectonic evolution of the East Kunlun Orogen and the Tethys, we present zircon U–Pb ages and Hf isotopic data, and whole-rock compositional and Sr–Nd–Pb...
This paper presents Sr-Nd-Pb isotopic and whole-rock geochemical data of Miocene to Pliocene volcanic rocks in the Eastern Anatolia (Turkey) aiming to unravel their sources and evolutionary history. The wide compositional range of lavas and pyroclastics includes basaltic andesite, basaltic trachyandesite, trachyandesite, andesite and trachydacite. These calc-alkaline volcanics are enriched in large...
New petrographic and geochemical data on magmatic sulphide inclusions (MSIs) are presented and discussed for 15 Quaternary volcanic centers of the Ecuadorian frontal, main and back volcanic arc. MSIs occur mostly in Fe–Ti oxides (magnetite and/or magnetite–ilmenite pair) and to a lesser extent in silicate minerals (amphibole, plagioclase, and pyroxene). MSIs are present in all volcanic centers ranging...
Throughout northeast China, eastern and southern Mongolia, and eastern Russia there is widespread Mesozoic intracontinental magmatism. Extensive studies on the Chinese magmatic rocks have suggested lithospheric mantle removal was a driver of the magmatism. The timing, distribution and potential diachroneity of such lithospheric mantle removal remains poorly constrained. Here, we examine successions...
Glass compositions of melt inclusions in olivine phenocrysts found in tephras derived from explosive eruptions of the four volcanoes along the volcanic front of the southernmost Andean Southern Volcanic Zone (SSVZ) are used to constrain primitive magma compositions and melt generation parameters. Primitive magmas from Hudson, Macá, and Melimoyu have similar compositions and are formed by low degrees...
The mineral composition of mantle xenoliths from kamafugites of the Bunyaruguru volcanic field has been determined. The major and some trace elements (Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K, Cr, Ni, Ba, Sr, La, Ce, Nd, Nb) has been analyzed in olivine, clinopyroxene, phlogopite, Cr-spinel, titanomagnetite, perovskite and carbonates of xenoliths and their host lavas. Bunyaruguru is one of three (Katwe-Kikorongo,...
The giant Yanbei tin ore deposit is the largest porphyry-type tin deposit in South China. The orebodies are hosted by the granite porphyry in the central part of the Yanbei volcanic basin in southern Jiangxi Province. The Yanbei volcanic-intrusive complex mainly consists of dacitic-rhyolitic volcanic rocks, granite, granite porphyry and diabase dikes. In previous papers, the granite porphyry was considered...
Neoarchean TTG-sanukitoid associations of contrasting scales occur within the Beit Bridge Complex terrane of the Limpopo Complex in southern Africa. These include the smaller ~2.65–2.63Ga Avoca granitoid and the voluminous ~2.73–2.64Ga Alldays granitoid. This study characterizes the wide compositional spectrum preserved in these two granitoids. The elliptical Avoca pluton consists of a biotite-amphibole-orthopyroxene±clinopyroxene-bearing...
Bubble nucleation and growth control the explosivity of volcanic eruptions, and the kinetics of these processes are generally determined from examinations of natural samples and quenched experimental run products. These samples, however, only provide a view of the final state, from which the initial conditions of a time-evolving magmatic system are then inferred. The interpretations that follow are...
Two typical lamproitic dykes were found in Noril'sk region of the north-western Siberian Craton, which according to mineralogical, geochemical and isotopic criteria belong to anorogenic, non-diamondiferous type of lamproites. According to the geologic relationships, they cut through the Noril'sk-1 intrusion of the Siberian flood basalt province and thus are younger than ~251Ma. 40Ar/39Ar dating of...
The Xiaoyao tungsten polymetallic skarn deposit in the eastern Jiangnan Massif of Yangtze Block is located at the contact between a granodiorite pluton and Sinian–Cambrian limestone. The intrusions in the tungsten-rich district comprise the Xiaoyao and other granodiorite plutons and granite porphyry dikes. The age determinations by LA–ICP–MS U–Pb dating of zircons indicate that the granodiorite formed...
The Neoproterozoic Malani Igneous Suite (MIS) is described as the largest felsic igneous province in India. The linearly distributed Sindreth and Punagarh basins located along eastern margin of this province represent the only site of bimodal volcanism and associated clastic sediments within the MIS. The in-situ zircon U-Pb dating by LA-ICPMS reveals that the Sindreth rhyolites were erupted at 769–762Ma...
The Dala diabase intrusion, at the southeastern margin of the Yardoi gneiss dome, is located within the outcrop area of the ~132Ma Comei Large Igneous Province (LIP), the result of initial activity of the Kerguelen plume. We present new zircon U-Pb geochronology results to show that the Dala diabase was emplaced at ~132Ma and geochemical data (whole-rock element and Sr-Nd isotope ratios, zircon Hf...
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