Noble gases trapped in meteorites are tightly bound in a carbonaceous carrier labeled “phase Q.” Mechanisms having led to their retention in this phase or in its precursors are poorly understood. To test physical adsorption as a way of retaining noble gases into precursors of meteoritic materials, we have performed adsorption experiments for Ar, Kr, and Xe at low pressures (10 4 mbar to 500 mba...

Hydrogen-lean kerogens (atomic H/C 0.4) isolated from the 2.5-billion-year-old (Ga) Mt. McRae Shale, Hamersley Group, at Tom Price, Western Australia, were studied via hydropyrolysis, a continuous-flow technique that degrades organic matter in a stream of high-pressure hydrogen assisted by a dispersed Mo catalyst. The hydropyrolysates yielded predominantly phenanthrene and pyrene, and higher po...

As kerogen is the main organic component in shale, the adsorption capacity, diffusion and permeability of the gas in kerogen plays an important role in shale gas production. Based on the molecular model of type II kerogen, an organic nanoporous structure was established. The Grand Canonical Monte Carlo (GCMC) and Molecular Dynamics (MD) methods were used to study the adsorption and diffusion ca...

This study investigates the nano to core-scale geomechanical properties of a maturity series organic-rich, calcareous shales buried 100°C–180°C, with focus on: (a) mechanical organic matter; (b) elastic response and anisotropy shale composite at micro core scale; (c) creep response. Atomic force microscopy was used target kerogen nanoscale resolution, it found that stiffness increased thermal f...

The potassium permanganate oxidation of methylated humic acid from a Spanish lignite yielded mainly straight-chain alkanes together with a mixture of fatty acids, methyl straight-chain alkyl ketones, aliphatic dicarboxylic, phenolic and benzenecarboxylic acids. Furthermore, some unusual compounds such as dehydroabietic and bromohydroxybenzoic acids and bis(2-ethylhexyl)phthalate were also ident...

The past decade has seen an explosion of new technologies for assessment of biogenicity and syngeneity of carbonaceous material within sedimentary rocks. Advances have been made in techniques for analysis of in situ organic matter as well as for extracted bulk samples of soluble and insoluble (kerogen) organic fractions. The in situ techniques allow analysis of micrometer-to-sub-micrometer-scal...

Sedimentary organic matter is formed by diagenesis (reactions in sediments up to 60°C, Tegelaar et al., 1989) and catagenesis (those >100°C induced by thermal cracking, Tissot and Welte, 1984) of biological material introduced during deposition from primary producers. Over 90% of this sedimentary organic matter is a non-hydrolyzable (i.e., immune to acid–base hydrolysis) macropolymer called ker...