Topic
Incompatible element
About: Incompatible element is a research topic. Over the lifetime, 2420 publications have been published within this topic receiving 154052 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: The Chachimbiro volcanic complex (CVC) is a composite volcano located in the frontal part of the Ecuadorian Quaternary Arc as discussed by the authors, and four periods of activity can be differentiated in its ∼400 ka-long volcanic history.
7 citations
Journal Article•
TL;DR: In this paper, the authors show that the mafic-intermediate intrusives in the Hudongri area, Chuncheon were derived from mantle material enriched by subduction.
Abstract: The intrusive rocks in the Hudongri area, Chuncheon located in central Gyeonggi Massif consist of gabbroic diorite and diorite. K-Ar age of biotite separated from diorite sample records middle Triassic age of 228 Ma. The intrusives are characterized by enrichment of MgO, Ni and Cr as well as large ion lithophile elements such as Sa and Sr, which is indicative of derivation of magma from enriched mantle. The intrusives also have enriched Sr-Nd isotopic compositions, which appear to result from a long-term incompatible element enriched mantle source with an effect of crustal contamination. Occurrence of abundant hydrous minerals such as amphiboles and biotite rather than anhydrous minerals of pyroxene and olivine in mafic intrusive as well as being plotted in volcanic arc field in tectonic environment discrimination diagram indicate the mafic-intermediate intrusives in the Hudongri area, Chuncheon were derived from mantle material enriched by subduction.
7 citations
TL;DR: The Virginia Dale intrusion is a granitic and monzogranitic composite body at the southern extent of the Sherman batholith in southeastern Wyoming and adjacent areas of Colorado as mentioned in this paper.
Abstract: The Virginia Dale intrusion is a granitic and monzogranitic composite intrusive body at the southern extent of the Sherman batholith in southeastern Wyoming and adjacent areas of Colorado. Within the study area, at the margin of the intrusion, mafic rock (diorite) is commingled with felsic rock (monzogranite) and intermediate rocks. Resulting features include pillows (some with zones of felsic or mafic enrichment at their margins), enclaves, mantled quartz grains, and alkali feldspar megacrysts. Intermediate rocks interpreted as hybrids include: (1) granodioritic hybrid; (2) main-phase hybrid; (3) granitoid hybrid; and (4) mafic hybrid. Each of the hybrids shows distinct textural and mixing relations. Mixing and hybridization models were evaluated using major-element, trace-element, and isotopic data. Major-element compositions of the hybrid rocks generally plot along simple mixing lines between mafic and felsic rocks. Incompatible element concentrations of the intermediate rocks are similar to, or greater than, concentrations in the felsic end-member. Trace-element data suggest that the variety of intermediate rocks resulted from chemical diffusion in addition to bulk mixing of heterogeneous end-members. Mafic rocks show a possible differentiation trend, in which the most primitive members are cumulates. The more evolved members show progressive LREE and incompatible element enrichment, growth of a negative europium anomaly (to Eu/Eu * = 0.61), and a correlated decrease in Mg-number (to 0.35). Virginia Dale isotopic data (ϵ Nd = 0± 1) are similar to values for the adjacent Sherman batholith, suggesting that both of these bodies formed by partial melting (at 1.43 Ga) of ca. 1.8-Ga crust in the Colorado province. Initial 87 Sr/ 86 Sr values are more heterogeneous, perhaps due to chemical diffusion.
7 citations
TL;DR: The Nadezhda body in the Lukkulaisvaara layered intrusion exhibits concentric zonation with an inward progression from a 0.5 to 1.0 m thick marginal layer of medium-to coarse-grained norites and gabbronorites that abruptly give way to fine-grain oikocrysts composing the rest of the body as mentioned in this paper.
Abstract: The 100 m thick and 700 m long Nadezhda body in the Lukkulaisvaara layered intrusion exhibits concentric zonation with an inward progression from a 0.5 to 1.0 m thick marginal layer of medium- to coarse-grained norites and gabbronorites that abruptly give way to fine-grained oikocrystic gabbronorites composing the rest of the body. The concentric zonation is additionally emphasized by well-developed alignment of plagioclase laths and orthopyroxene oikocrysts parallel to the outer contacts of the body, pegmatitic gabbronorite segregations in the centre of the body and slight inward decrease in whole-rock Mg# and Cr and increase in incompatible elements. The body has distinctly higher whole-rock Mg# and lower concentrations of all incompatible components than its host rocks. It is enveloped by highly altered marginal anorthosites belonging to host norites and gabbronorites. We interpret the Nadezhda body as a portion of high Mg# (∼75%) and incompatible element-poor (∼20 ppm, Zr; ∼10 ppm, total REE; ∼0.20 wt%, TiO2) magma that replenished the evolving chamber and became trapped within the cumulate pile. Recrystallization of adjacent rocks by volatiles exsolved from the magma upon emplacement resulted in formation of marginal anorthosites. Upon cooling the magma started to crystallize medium- to coarse-grained norites along its margins, but subsequent decompression and loss of volatiles led to rapid crystallization of magma into fine-grained oikocrystic gabbronorites. Solidification of the remaining residual liquid gave rise to pegmatitic gabbronorite segregations.
7 citations
01 Jan 1995
TL;DR: In this article, geochemical data from plagioclase-hosted silicate melt inclusions from Leg 140, Hole 504B diabase dikes are reported, which are significantly more depleted than normal (N-type) mid-ocean-ridge basalt (MORB) and are consistent with being produced by 8%-16% incremental or open-system melting with 2% residual porosity in the peridotite source.
Abstract: Geochemical data from plagioclase-hosted silicate melt inclusions from Leg 140, Hole 504B diabase dikes are reported. Hand-picked plagioclase grains were heated to 1260°-1280°C to remelt the glass inclusions and to infer trapping temperatures. The samples were then polished to expose the inclusions, which were analyzed by electron and ion microprobes. Inclusion compositions are mainly in equilibrium with the host plagioclase and are more depleted in incompatible elements than the host rock. Simple crystal-liquid equilibrium calculations show that the melt inclusions could have been in equilibrium with depleted abyssal peridotite diopsides, whereas whole-rock basalt compositions generally could not have been. The melt inclusions are significantly more depleted than normal (N-type) mid-ocean-ridge basalt (MORB) and are consistent with being produced by 8%-16% incremental or open-system melting with 2% residual porosity in the peridotite source. These magmas were formed during pressurerelease melting of the mantle over a range of depths between 30 and 15 km.
7 citations