An understanding of enamel diagenesis is necessary to ensure sound isotopic palaeodietary and palaeoenvironmental reconstructions. Although carbon isotope signals of browsing and grazing herbivores remain distinct in enamel even after millions of years, subtle alteration of isotopic signatures does occur. To better understand this change we analysed modern and fossil enamel from a number of Sou...

Using solid-state cross-polarization-magic-angle-spinning (CPMAS) C and N nuclear magnetic resonance (NMR) and 2-D double cross polarization (DCP) MAS N C NMR techniques, microbially degraded Botryococcus braunii was analyzed to study the chemical nature of organic nitrogen in the algal residue. The amide linkage, as found in protein, was observed as the major nitrogen component in 201-day-old ...

This paper presents a mineralogical and chemical investigation of shale deposits from the U.S. Gulf coast in order to document the mechanisms and reactions involved in the diagenetic conversion of smectite into illite. Cuttings from the 1,250 to 5,500 m stratigraphic interval of a well were sorted by grain size and analzyed by x-ray diffraction to assess chemical and mineralogical trends with d...

The redeposition of pristine phosphorite plays an important role in phosphorus accumulation, which created reworked extensively on the continental shelf. This paper, using geochemical analysis combined with data from petrology and diagenesis, focuses reconstruction formation processes Late Cretaceous Thaniyat deposition northwestern Saudi Arabia, is a part famous large Neo-Tethys Ocean’s deposi...

Early diagenetic modification of magnetic properties is an important process in marine sediments, but temporal and spatial variability of diagenetic processes have rarely been reported for recent coastal sediments. The magnetic properties of sediments from the Ria de Vigo (NW Spain) define a marked three-part zonation with depth. The uppermost zone is magnetically dominated by (titano-)magnetit...

Recent experiments have heightened our understanding of reactions which can stabilize biomolecules during early diagenesis, yet little remains known about how groundwater chemistry aid or hinder molecular preservation within a bone through geologic time. To elucidate this issue, we conducted actualistic decay employing varied fluid compositions to simulate suite groundwaters. Modern domestic ch...

In order to establish the magnetic carriers and assess the reliability of previous paleomagnetic results obtained for Eocene marine marls from the south Pyrenean basin, we carried out a combined paleoand rock-magnetic study of the Pamplona-Arguis Formation, which crops out in the western sector of the southern Pyrenees (N Spain). The unblocking temperatures suggest that the characteristic reman...