Introduction: The Isidis impact basin was formed in ancient cratered uplands but has since experienced tectonic deformation of the impact basin rim (Nili Fossae), volcanic modification of the western basin rim (Syrtis Major Planitia), and filling of the Isidis Basin (Hesperian ridged plains and the Vastitas Borealis Formation). This wide array of post-basin geomorphic units led to the general i...

Introduction: The zoning patterns of light lithophile elements (LLEs: Li, Be, B) in pyroxenes of some Martian meteorites have been used to suggest that the parent basalts were water-saturated, which exsolved and lost an aqueous phase through degassing and eruption, causing depletion in LLEs in the pyroxene rims [1]. In contrast, other investigators have suggested a diffusion controlled fraction...

Mare basalts collected at the Apollo 15 landing site are classified as belonging to either quartz-normative suite or olivine-normative suite, based on differences in whole-rock major element chemistry. A wide range of textures displayed within samples from both suites, which provide insight into eruption processes Moon. Here we use crystal size distribution (CSD) analysis and spatial pattern (S...

Sixteen new K-Ar dates are presented from Tasmanian and Bass Basin basalts, more than doubling the previously published number. Eight volcanic regions are described, based on boundaries established on the range of the basalt types contained in each geographic region. Volcanism occurred within the span from Eocene to Miocene (47 to 13+ Ma), but mainly within the time range Middle Eocene to Early...

The metal and sulfide phases in the Luna 24 soil samples were studied with the optical microscope and the electron microprobe. The compositions of the metal particles fall into three groups based on their Ni and Co contents: (1) Samples of meteoritic composition which have undergone metamorphism on the lunar surface. (2) Samples of submeteoritic, low Ni and low Co contents, including most of th...

A set of time integrated cosmogenic 3He production rates in olivines for the last 1.35 Ma are presented. We investigated three basaltic lava flow tops from Lanzarote, Canary Islands, Spain. The 40Ar/39Ar ages determined for those basalt flows by incremental laser heating of leached groundmass samples are 152 þ 26 ka, 281 þ 19 ka and 1.35 þ 0.01 Ma ( þ 2c). Three or four different olivine phenoc...

Petrological and geochemical studies of lamproites can provide useful insights into the nature their lithospheric mantle sources, but mineralogical diversity has complicated our understanding primary/parental melt composition, volatile (CO2, H2O) inventory magmatic evolution. To help address this issue, we present a detailed study different generations (primary, pseudosecondary, secondary) crys...

This contribution assesses the availability of catabolic energy for microbial life during water-rock reactions in the flanks of mid-ocean ridges, where basaltic and ultramafic rocks interact with circulating seawater. In addition to equilibrium thermodynamic computations, results for kinetic reaction paths are presented. In these calculations, it is assumed that dissolution of olivine and basal...

Quantitative textural analysis is a powerful tool in the investigation of basalt crystallization. We present the first comprehensive crystal size distribution analysis of Apollo 17 high-titanium lunar basalts, with a focus on ilmenite. Crystal size distributions of ilmenite, pyroxene, plagioclase, olivine and armalcolite were determined for 18 high-Ti mare basalt samples from the Apollo 17 miss...