The putative occurrence of methane in the Martian atmosphere has had a major influence on the exploration of Mars, especially by the implication of active biology. The occurrence has not been borne out by measurements of atmosphere by the MSL rover Curiosity but, as on Earth, methane on Mars is most likely in the subsurface of the crust. Serpentinization of olivine-bearing rocks, to yield hydro...

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...

Introduction: Study of the Martian crust by orbital spectroscopy and SNC meteorites has so far only recognized subalkaline volcanic rocks. However, Spirit rover measured high alkalis and low silica in picritic basalts on the Gusev plains [1,2], allowing the possibility that alkaline differentiates might occur. Isolated rocks having mildly alkaline compositions and distinctive spectra have now b...

Osmium isotope compositions and concentrations of Re, platinum group elements (PGE), and Au were determined for host peridotites (serpentinites and harzburgites) and hydrothermally altered ultramafic wall rocks associated with Mother Lode-type hydrothermal gold-quartz vein mineralization in the Alleghany district, California. The host peridotites have Os isotope compositions and Re, PGE, and Au...

A detailed organic geochemical study; utilising petrography, biomarker hydrocarbon analysis and high temperature GC analysis of extractable wax hydrocarbon constituents was performed on four marginally oil window-mature source rocks from the Shahejie Formation (Eocene), Damintun depression in eastern China. The main maceral components in the source rocks were vitrinite, liptinite and exinite, w...

Single detrital monazite grains from the Dharamsala and Lower Siwalik Formations (early to mid-Miocene continental foreland basin sediments in NW India) have been dated by two techniques; isotope dilution thermal ionization multicollector mass spectrometry (ID-TIMS) and laser ablation plasma ionization multicollector mass spectrometry (LA-PIMMS). The results give U–Th–Pb isotopic ages of c. 400...

the study area is located in the northeast of iran. miankuhi formation is 500m thick and comprises homogeneous shales, brown granular sandstone and siltstone. in this study, 45 samples were taken from miankuhi shales and sandstones in order to determine their tectonic origin by using a polarizing microscope. samples were analysed by x-ray fluorescence (xrf) method to determine their chemical co...