Owing to advances in microanalytical techniques over the last 15 years, there is a growing database on the volatile contents of subduction-related magmas as recorded in melt (glass) inclusions trapped in phenocrysts in volcanic rocks. Basaltic magmas from subduction zones show a wide range of water contents, ranging from as high as 6–8 to b0.5 wt.% H2O. Variations are related in some places to ...

Whole-rock geochemical data on basaltic to rhyolitic samples from 12 volcanic centers are used to constrain the role of continental crust in the genesis of magmas formed beneath the anomalously wide subduction-related volcanic arc in Ecuador. Relatively homogeneous, mantle-like, isotopic compositions across the arc imply that the parental magmas in Ecuador were produced largely within the mantl...

[1] We present major, volatile, and trace elements for quenched glasses from the Fonualei Spreading Center, a nascent spreading system situated very close to the Tofua Volcanic Arc (20 km at the closest), in the northeast Lau Basin. The glasses are basalts and basaltic andesites and are inferred to have originated from a relatively hot and depleted mantle wedge. The Fonualei Spreading Center sh...

Various evidence, including size and volume of the Siberian Traps, timing and duration of eruptions, paleotectonic and paleogeographic reconstructions, lithospheric structure, heat flow, trace element and radiogenic isotope compositions of lava are reviewed in this chapter. The major evidence may be summarized as follows. The Siberian Traps erupted in a number of brief volcanic events from the ...

this paper presents the new geochemical isotopes sr and nd, and the mineralization data for the south neyshabour volcanic rocks located in ne iran. based on the chemical classifications, the studied rocks are basaltic trachy andesite, trachy andesite, trachyte, and trachy dacite in composition. all the analyzed volcanic rocks display enrichment in light rare earth elements (lree) relative to th...

kuh-e-siah is located in the north of gavkhuni lagoon and east of the varzaneh (se of isfahan) and is a part of urumieh-dokhtar magmatic arc (udma). the volcanic rocks of this area are vesicular basalt and basaltic andesite with late miocene age. the most common textures of these rocks are porphyry, microlitic porphyritic, hyaloporphyric and vesicular. plagioclase, olivine and clinopyroxene are...

The possibility of understanding natural processes leading to explosive events in volcanic systems provides advantages for a better management of possible volcanic crises. On account of the possibility of the occurrence of other phenomena, such as tsunamis, the explosions driven by submarine volcanic systems are of particular interest, although little investigated. The recent sudden increase in...