An ion probe study of trace elements in Mg-rich clinopyroxene phenocrysts in primitive Aleutian lavas provides constraints on the genesis of Aleutian adakites, and possible insights into the source of common Aleutian magmas. Clinopyroxene (cpx) phenocrysts in the primitive adakites have high Sr and Nd=Yb compared to cpx in Aleutian basalts. In the adakites, Sr and Nd=Yb are highest for high Mg#...

Lavas from Afanasy-Nikitin Rise, possibly the Late Cretaceous product of the Crozet hotspot, cover a wide range of isotopic compositions that includes the lowest (Pb/Pb)t (to 16.77) and «Nd(t) (to 28) values yet found among oceanic islands or spreading centers worldwide, as well as high (Sr/Sr)t (to 0.7066). In contrast, young basalts from the Crozet Archipelago exhibit a narrow range of variat...

صخلملا The aim of this study isto examine whether radiofrequency (RF) used in cellular phone communications at a specific absorption rate (SAR) less than 1.2 w/kg could increase the spontaneous rate of sister chromatid exchanges (SCE) or elicit alterations both in the cell replication index (CRI) and mitotic index (MI) in human peripheral blood lymphocytes. Whole blood samples were obtained fro...

Plio–Pleistocene (3.4–0.125 Ma) post-plateau magmatism in the Meseta del Lago Buenos Aires (MLBA; 46.7jS) in southern Patagonia is linked with the formation of asthenospheric slab windows due to ridge collision along the Andean margin f 6 Ma ago. MLBA post-plateau lavas are highly alkaline (43–49% SiO2; 5–8% Na2O+K2O), relatively primitive (6–10% MgO) mafic volcanics that have strong OIB-like g...

Continental flood basalts and mid-ocean ridge (MOR) tholeiitic basalts have distinctly different 14 3 Ndf1 44 Nd which may permit a priori distinctwn between '"continental" and "oceanic" igneous rocks. Initial 14 3 NdJI 4 4 Nd of continental igneous rocks through time fall on a Sm/Nd evolution curve with chondritic REE abundance ratio. These observations indicate that many continental igneous r...

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...

Abstract The chemical composition of the wood reflects soil over which corresponding tree has developed. Multi-elemental and isotopic signatures, are characteristic underlying rock substrates, potentially powerful tools for determining provenance. These tracers special interest charred archaeological because they circumvent some limitations dendrochronological provenancing linked to tree-ring l...

The discovery of superconductivity in Nd${}_{1\ensuremath{-}x}$Sr${}_{x}$NiO${}_{2}$ has resulted a flurry experimental and theoretical work to understand the nature nickelate as compared that cuprates pnictides. Here, authors use combination LDA+U linear-response methods study magnetic exchange interactions Nd${}_{1\ensuremath{-}x}$Sr${}_{x}$NiO${}_{2}$. analysis reveals an underlying Mott ins...

The Pirrit Hills are located in the Ellsworth–Whitmore Mountains of West Antarctica. granite exhibits significant negative Eu anomalies (Eu/Eu* = 0.01~0.25) and a REE tetrad effect indicating intensive magmatic differentiation. Whole-rock Rb-Sr Sm-Nd geochronologic analysis gave respective ages 172.8 ± 2.4 Ma with initial 87Sr/86Sr 0.7065 0.0087 169 12 144Nd/143Nd 0.512207 0.000017. isotopic ra...