The Curiosity rover in Gale crater is investigating a mineral transition observed from orbit – an older “clay unit” to younger “sulfate hypothesized reflect the aridification of Mars’ climate. Below this transition, detected crystalline Ca-sulfates with minor Fe-sulfates but also found that some fraction rock’s bulk SO3 often poorly constrained X-ray amorphous component. Here, we characterize a...

Artificial diagenesis of the intra-crystalline proteins isolated from Patella vulgata was induced by isothermal heating at 140 °C, 110 °C and 80 °C. Protein breakdown was quantified for multiple amino acids, measuring the extent of peptide bond hydrolysis, amino acid racemisation and decomposition. The patterns of diagenesis are complex; therefore the kinetic parameters of the main reactions we...

During deposition of Precambrian iron formation, the combined sedimentation of ferrihydrite and phytoplankton biomass should have facilitated Fe(III) reduction during diagenesis. However, the only evidence for this reaction in iron formations is the iron and carbon isotope values preserved in the authigenic ferrous iron-containing minerals. Here we show experimentally that spheroidal siderite, ...

Abstract Pyrite framboids (spherical masses of nanoscale pyrite) are among the earliest textures pyrite to form in sediments. It has been proposed that their trace-element (TE) contents can be used track TE composition water column which they formed. However, it is not clear how these TEs associated with framboidal grains. For instance, important know whether incorporated uniformly or enriched ...

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...

Gale Crater, the Mars Science Laboratory (MSL) landing site, contains a central mound, named Aeolis Mons (informally Mount Sharp) that preserves 5 km of sedimentary stratigraphy. Formation scenarios include (1) complete filling of Gale Crater followed by partial sediment removal or (2) building of a central deposit with morphology controlled by slope winds and only incomplete sedimentary fill. ...

The material properties of sedimentary rocks are controlled by a range of parameters, including grain size, sorting, and modification of the original sediment through the diagenetic processes of compaction and cementation. To isolate the effects of diagenesis, and explore how they modify permeability, we quantified changes in grain and pore morphology accompanying progressive diagenesis of a si...