The Ontong Java-Manihiki-Hikurangi plateau (OJMHP) is considered to have originated from a starting mantle plume, and have been rifted apart by two spreading ridges. However, the ages of these spreading ridges and their possible interactions with the presumed mantle plume are unclear. The Manihiki-Hikurangi plateau has been rifted apart by the Osbourn Trough which formed the southwestern Pacifi...

The nature of source rocks of basaltic magmas plays a fundamental role in understanding the composition, structure and evolution of the solid earth. However, identification of source lithology of basalts remains uncertainty. Using a parameterization of multi-decadal melting experiments on a variety of peridotite and pyroxenite, we show here that a parameter called FC3MS value (FeO/CaO-3*MgO/SiO...

The last major phase of lunar volcanism produced extensive high-titanium mare deposits on the western nearside which remain unsampled by landing missions. The visible and near-infrared reflectance properties of these basalts are examined using Clementine multispectral images to better constrain their mineralogy. A much stronger 1 }am ferrous absorption was observed for the western high-titanium...

The Columbia River Basalt Group in the northwestern United States, comprising about 230,000 cubic kilometres of rock, exhibits unusual patterns in lava distribution, geochemistry and its apparent relationship to regional tectonics. Consequently, there is little consensus on the origin of its magmas. Here, we examine the isotopic ratios of Sr, Nd, Pb and Os and traceelement abundances in Columbi...

[1] The last major phases of lunar volcanism produced spectrally unique high‐titanium basalts on the western nearside of the Moon. The Moon Mineralogy Mapper (M) on Chandrayaan‐1 has provided detailed measurements of these basalts at spatial and spectral resolutions necessary for mineralogical interpretation and mapping of distinct compositional units. The M3 imaging spectrometer acquired data ...

Chlorine stable isotope compositions (delta37Cl) of 22 mid-ocean ridge basalts (MORBs) correlate with Cl content. The high-delta37Cl, Cl-rich basalts are highly contaminated by Cl-rich materials (seawater, brines, or altered rocks). The low-delta37Cl, Cl-poor basalts approach the composition of uncontaminated, mantle-derived magmas. Thus, most or all oceanic lavas are contaminated to some exten...

Metal-oxidizing bacteria may play a key role in the submarine weathering of volcanic rocks and the formation of ferromanganese crusts. Putative fossil microbes encrusted in Mn oxide phases are commonly observed on volcanic glasses recovered from the deep ocean; however, no known Mn(II)-oxidizing bacteria have been directly identified or cultured from natural weathered basalts. To isolate epilit...

Lunar highland meteorites contain small proportions of mare basalt fragments, which are important for defining lunar basalts in areas not visited by Apollo/Luna. We analyzed seven mare basalt fragments from three highland meteorites, and retrieved the Ti contents of their parent magmas from core pyroxene compositions. The analyzed clasts span the range of VLT and low-Ti, basalts in Apollo & Lun...

The Basalt of Summit Creek is an enigmatic basalt unit that is about 55 million years (Ma) in age, located south of Mount Rainier. These basalts formed in a transitional time between the formation of the Coastal Range Basalts and the present Cascade arc. Through geochemical and paleomagnetic techniques, samples were collected and analyzed. Paleomagnetic samples showed nearly complete post erupt...