In the study presented here, we investigated K-Ar age determination and petrological significance of trace element compositions Bitlis (Eastern Anatolia) ignimbrites associated with explosive activities well-known Nemrut volcano. geochronological dating ignimbrite flow deposits gave 790 ka which corresponds to first products pre-caldera stages stratovolcano. trachydacitic shoshonitic affinity a...

This article reports new geochemical, Sr-Nd-Hf-Pb and Re-Os data on the rocks of Middle Paleoproterozoic (1.99 Ga) Tiksheozero ultramafic-alkaline-carbonatite complex confined to northeastern margin Karelian Craton. We focus poorly studied silicate rocks. Based petrographic geochemical research, are subdivided into two groups: an ultramafic-mafic series depleted in REE, other incompatible eleme...

An abundance of the trace elements has been determined in olivine Archean spinel-bearing phlogopite harzburgite enclave (sample UR17/2) from Bug granulite complex Ukrainian Shield by SIMS analysis. Major were analyzed SEM-EDS and EPMA The shows a homogeneous chemical composition: MgO — 45.20—45.64 wt.%, FeO 13.66—14.23 with Fo85—86 Fe/Mn ratio 68.3—68.6 which corresponds to 60—70 peridotites. N...

Post-collision Pliocene-Quaternary basaltic rocks outcrop in the Kerman Cenozoic Magmatic Arc (KCMA) to northwest and east of Shahr-e-Babak city. These porphyritic vesicular are composed essentially clinopyroxene, olivine, plagioclase. basalts display alkaline affinity negative Ta, Zr, Rb anomaly, but slightly Nb relative elements with similar compatibility, positive Ba, K, Sr suggesting their ...

Surface meltwater runoff is believed to be the main cause of alarming mass loss in Greenland Ice Sheet (GrIS); however, recent research has shown that a large amount not directly drained or refrozen but stored form firn aquifers (FAs) interior GrIS. Monitoring changes FAs over GrIS great importance evaluate stability and balance ice sheet. This challenging because are visible on surface direct ...

finding the optimum overrelaxation parameter o¡¡, is an important and often a difficult part of the problem [1, p. 257]. When A is a 2-cyclic, consistently ordered, real symmetric, positive-definite matrix (this will be assumed in the rest of the paper), only the spectral radius p(£i) of the associated Gauss-Seidel iteration matrix £i is needed to determine the optimum parameter co¡, [2, p. 109...

Abstract Ocean-island basalts (OIBs) are considered to be messengers from the deep mantle, yet filtering effect of plumbing systems that bring OIB melts surface remains poorly assessed. We investigated volcanic products El Hierro island (Canary Islands) textural and chemical perspectives. The majority geochemical data cluster at relatively fractionated basaltic compositions 5 wt% MgO. Compositi...

The Alada? melange is located between Mesozoic Tauride carbonate platform units and the Late Cretaceous Pozant?-Karsant? ophiolite its metamorphic sole. comprises a lower, mainly sedimentary unit, composed of variably disrupted thrust sheets deep-sea sediments, with localized matrix mass-flow turbidity current deposits. upper, volcanic-sedimentary highly basalt-pelagic carbonate-radiolarite uni...