This study presents Ba isotope compositions of ocean island basalts (OIB) from the Azores Archipelago to investigate origin enriched components within their mantle sources. These samples have large variations in radiogenic Sr-Nd-Pb-Hf compositions, indicating that they tap highly heterogeneous They display two types characteristics. Samples Faial, Pico, São Jorge, and Miguel Islands exhibit hom...

Chaldoran area in NW of Iran has Mesozoic oceanic crust basement. The studied rocks of this region can be divided into three groups: ophiolitic gabbros and pillow lavas, ophiolitic volcanoclastics and Eocene lava flows. Ophiolitic mafic rocks show continental volcanic arc natures and Eocene lava flow shows OIB-like nature. During the Mesozoic,the Chaldoran region was situated in the active cont...

The initiation of a continental rift or the birth an oceanic basin, and their long-term evolution, are challenges in understanding evolution regional global tectonics. Rifts develop within interior margins plates, essentially as extensional structures, they have been studied widely since discovery plate eastern segment Paleo-Tethys traversed central Asia, its structural features, timing, geolog...

Detection of Hadean isotopic signatures within modern ocean island basalts (OIB) has greatly influenced understanding Earth's earliest history and long-term dynamics. However, a relationship between two tools for studying early Earth processes, the short-lived 146Sm-142Nd 182Hf-182W systems, not been established in this context. The differing chemical behavior these systems means that they are ...

Bulk-rock geochemical compositions of hypabyssal kimberlites, emplaced through the Archaean Kaapvaal craton and Proterozoic Namaqua–Natal belt, are used to estimate close-to-primary magma compositions of Group I kimberlites (Mg-number 1⁄4 0 82–0 87; 22–28 wt % MgO; 21–30 wt % SiO2; 10–17 wt % CaO; 0 2–1 7 wt % K2O) and Group II kimberlites (Mgnumber 1⁄4 0 86–0 89; 23–29 wt % MgO; 28–36 wt % SiO...

Oceanic basalts, such as mid-ocean ridge basalts (MORB) and ocean island basalts (OIB), are characterized by large isotopic and trace element variability that is hard to reconcile with partial melting of a peridotitic mantle alone. Their variability has been attributed to the presence of heterogeneities within the mantle, such as recycled crust, metasomatized material or outer core contribution...

The upper mantle is widely considered to be heterogeneous, possibly comprising a “marble-cake” mixture of heterogeneous domains in a relatively well-mixed matrix. The extent to which such domains are capable of producing and expelling melts with characteristic geochemical signatures upon partial melting, rather than equilibrating diffusively with surrounding peridotite, is a critical question f...

The accurate knowledge of sea ice parameters, including sea ice thickness and snow depth over the sea ice cover, are key to both climate studies and data assimilation in operational forecasts. Large-scale active and passive remote sensing is the basis for the estimation of these parameters. In traditional altimetry or the retrieval of snow depth with passive microwave sensing, although the sea ...