Sökning: "diagenesis"
Visar resultat 16 - 20 av 23 avhandlingar innehållade ordet diagenesis.
16. Deposition, palaeoecology and diagenesis of the Silurian reef-like limestones on Gotland
Sammanfattning : Several Silurian (Wenlockian-Ludlovian) reef-like limestones on Gotland wereselected for studies of depositional, palaeoecological, and diagenetic conditions. Thereef-like limestones were deposited on a warm, shallow and open marine shelf. LÄS MER
17. Genesis and Diagenesis of the Phosphatic Hardground of the Holm Dal Formation (Late Middle Cambrian), North Greenland
Sammanfattning : The phosphatic hardground of the Holm Dal Formation (late Middle Cambrian) of North Greenland is composed of two parts: one basal with abundant allochthonous material and an upper part without an allochthonous component. It was formed by release of phosphate, by bacterial degradation, from organic matter which accumulated in lime mudstones on which the hardground developed. LÄS MER
18. Hydrothermal alteration of organic matter at spreading centers
Sammanfattning : Alteration of organic matter, mainly amino acids, at sub-seafloor hydrothermal conditions has been investigated by performing laboratory experiments and by studying deep-sea sediments from hydrothermally active areas on the northern Juan de Fuca Ridge, northeast Pacific Ocean.Quaternary sediments from Middle Valley and the eastern flank of the Juan de Fuca Ridge recovered during the Ocean Drilling Program Legs 139 and 168 have been analyzed for total hydrolyzable amino acid concentrations, individual amino acid abundances and stereochemistry in order to evaluate the effects of hydrothermal stress on the decomposition of sedimentary amino acids. LÄS MER
19. Marine oolites as proxies for palaeoenvironmental reconstructions during extinction events
Sammanfattning : At present time, it has been stated that “Human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming, with global surface temperature reaching 1.1°C above 1850–1900 in 2011–2020”. LÄS MER
20. Our Bones, who art contaminated : Glues, strontium isotopes, and mobility in early Swedish Christians
Sammanfattning : This thesis aims to build upon previous research into contamination and its effects on isotopes by focusing on the strontium isotopic ratio (87Sr/86Sr), which is used in mobility studies to study the movements of past humans and animals and to build past economic trading networks. Contamination is a broad topic, and in the scope of this thesis, it concerns the introduction of contaminants from the soil after interment and the post-excavation preservation efforts. LÄS MER
