Melting of mafic veins in a marble-cake mantle may play an important role in generating isotopic and chemical heterogeneities in mid-ocean ridge and ocean island basalts. Mafic veins have lower solidi than mantle peridotite and will be preferentially sampled during partial melting, particularly at low melt fractions. However, the abundance of mafic components in the mantle or their role during ...

We investigated the interactions between CO2-rich fluids and Mg-silicate minerals using experiments to provide information on reaction rates and to identify potential catalysts for the reactions, and studies of natural analogues to assess the conditions that lead to massive carbonation of ultramafic rocks and thus the potential for field-scale implementation. Key findings from our exploratory w...

Introduction: The compositions of Martian (SNC) meteorites provide geochemical parameters thought to be diagnostic for Mars [1,2]. The validity of these geochemical fingerprints is important because SNC element ratios are the basis for estimates of the planet’s bulk composition [3]. The compositions of minerals in these meteorites are distinct from terrestrial rocks and are also hypothesized to...

[1] Spirit’s Mössbauer (MB) instrument determined the Fe mineralogy and oxidation state of 71 rocks and 43 soils during its exploration of the Gusev plains and the Columbia Hills (West Spur, Husband Hill, Haskin Ridge, northern Inner Basin, and Home Plate) on Mars. The plains are predominantly float rocks and soil derived from olivine basalts. Outcrops at West Spur and on Husband Hill have expe...

[1] Spirit’s Mössbauer (MB) instrument determined the Fe mineralogy and oxidation state of 71 rocks and 43 soils during its exploration of the Gusev plains and the Columbia Hills (West Spur, Husband Hill, Haskin Ridge, northern Inner Basin, and Home Plate) on Mars. The plains are predominantly float rocks and soil derived from olivine basalts. Outcrops at West Spur and on Husband Hill have expe...

Analyses by the Mars Exploration Rover (MER), Spirit, of Martian basalts from Gusev crater show that they are chemically very different from terrestrial basalts, being characterized in particular by high Mgand Fe-contents. To provide suitable analog basalts for the International Space Analogue Rockstore (ISAR), a collection of analog rocks and minerals for preparing in situ space missions, espe...

We compile a 3.7-b.yr.-long time series of ultramafic and mafic rocks including extrusives and shallow intrusives (dikes and sills). We infer that peaks in the time series represent mantle plume events. Rocks erupted from plumes are becoming more Ti rich through time, and several rock types having 118 wt % MgO are Phanerozoic analogs for komatiites. These include meimechites, ankaramites, and r...

Volcanism is a substantial process during crustal growth on planetary bodies and well documented to have occurred in the early Solar System from the recognition of numerous basaltic meteorites. Considering the ureilite parent body (UPB), the compositions of magmas that formed a potential UPB crust and were complementary to the ultramafic ureilite mantle rocks are poorly constrained. Among the A...

The extension of subduction processes into the Eoarchaean era (4.0-3.6 Ga) is controversial. The oldest reported terrestrial olivine, from two dunite lenses within the ∼3,720 Ma Isua supracrustal belt in Greenland, record a shape-preferred orientation of olivine crystals defining a weak foliation and a well-defined lattice-preferred orientation (LPO). [001] parallel to the maximum finite elonga...

Abundant mafic and ultramafic rocks including basalts, komatiitic basalts, and peridotites occur in the Proterozoic Sibao Group, northern Guangxi Province, China. Whereas the basalts are generally pillow lavas, the komatiitic basalts are typically spinifex-textured and, in a few cases, show pyroxene accumulation associated with Ni Cu (PGE) sulfide deposits. The peridotites occur in the lower po...