The geochemical behaviors of Vand Sc during partial melting are more similar to each other than to most other elements but, in detail, the partitioning of V is redox-sensitive whereas that of Sc is not. The V/Sc ratio in basalts is shown here to be a sensitive and robust recorder of the oxygen fugacity (fO2) of their mantle source regions. The use of V/Sc ratios differs from the use of V and/or...

[1] These first measurements of specific surface area (SSA) of bulk samples of subsurfacemarine basalts were undertaken to determine the potential area available for microbial colonization. SSA ranged from 0.3 to 52 m/g of basalt with the lowest value coming from pillow basalt and the highest value from breccia. The average for massive and pillow basalts combined was 2.3 m/g. The total specific...

We report isotopic and chemical compositions of unusual tridymite–hercynite xenoliths in middle Miocene Niutoushan tholeiites from the southeast coastal area of China. These xenoliths are characterized by positive cerium (Ce) anomalies and extremely high Al2O3 (32–34 wt.%) and total iron oxide (20–22%). They have Sr/Sr of 0.7050–0.7058, eNd(0) values of + 3.2 to + 4.2, Pb/Pb ratios of 18.8–19.1...

The origin of continental flood basalts has been debated for decades. These eruptions often produce millions of cubic kilometers of basalt on timescales of only a million years. Although flood basalts are found in a variety of settings, no locale is more puzzling than cratonic areas such as southern Africa or the Siberian craton, where strong, thick lithosphere is breached by these large basalt...

The multispectral images of the lunar limb and farside obtained by the solid state imaging (SSI) system on board the Galileo spacecraft provide the first new pulse of compositional data of the Moon by a spacecraft in well over a decade. The wavelength range covered by SSI filters (0.4-1.0 }•m) is particularly sensitive to the composition of mare basalts, the abundance of mafic (ferrous) mineral...

This paper presents new U–Th/He crystallization and He exposure ages on olivine for a suite of basalt samples from the Snake River Plain, Idaho. The results provide the first demonstration that U–Th/He geochronology can be successfully applied to Late Quaternary basalts using measurements of olivine phenocrysts as opposed to U-rich minerals. The approach employs abrasion to remove the outer rin...

[1] Using the Moon Mineralogy Mapper(M), we examine the Marius Hills volcanic complex for the first time from 0.46 to 2.97 mm. The integrated band depth at 1 mm separates the mare basalts on the plateau in two units: (1) a strong 1 mm band unit of localized lava flows within the plateau that has similar olivine‐rich signatures to those of the nearby Oceanus Procellarum and (2) a weaker 1 mm ban...

Rare earth abundances were determined by neutron activation in twenty Hawaiian lavas and one diabase of known chemical and mineralogical compositions. These results demonstrate a systematic relationship between the absolute or relative rare earth abundances and the petroehemistry of these rocks. Three distinct lava groups are recognized. These correspond to: (1) tholeiites, (2) alkali series, (...

Mafic rocks including basalts and gabbros are the main constituents of Birjand ophiolites. They are found in several places and show low grade metamorphism in the field and under the microscope. Chondrite-normalized REE patterns for basalts and gabbros indicate that these rocks are transitional-enriched to depleted mid-oceanic ridge basalts respectively. Otherwise, N-MORB normalized trace eleme...