Sökning: "datering"
Visar resultat 21 - 25 av 25 avhandlingar innehållade ordet datering.
21. Setting the Holocene clock using varved lake sediments in Sweden
Sammanfattning : The aim of this thesis was to study annually laminated (varved) Holocene lake sediment in Sweden, their formation and their potential as chronological and palaeoecological archives. Five lakes with continuous Holocene varved lake sediment sequences in northern (Västerbotten) and west central Sweden (Värmland) were investigated. LÄS MER
22. Quantification Methods for Clinical Studies in Nuclear Medicine - Applications in AMS, PET/CT and SPECT/CT
Sammanfattning : An essential part of the development of new radiopharmaceuticals for use in diagnostic nuclear medicine is the determination of its biokinetic properties. The uptake and turn-over of the radiopharmaceutical in the source organs is of great interest since this could determine whether the radiopharmaceutical would be suitable for clinical use or not. LÄS MER
23. Late Weichselian and early Holocene changes of vegetation, climate and sea level on the Skagi peninsula, northern Iceland
Sammanfattning : Sediment sequences from five lakes on the Skagi peninsula, northern Iceland, were subjected to mineral magnetic analysis, carbon analysis, pollen analysis, plant macrofossil analysis, diatom analysis, radiocarbon dating and tephra analysis in order to make detailed reconstructions of vegetation, climate and sea level during the Late Weichselian and Early Holocene. The main purpose was to investigate if the dramatic deglacial climatic shifts recorded in proxy records from the North Atlantic region, such as ice cores, marine sediments and lake sediments, also are registered in Skagi lake sediments, which would be expected considering Iceland´s position in the middle of the North Atlantic Ocean, within the range of the Late Weichselian–Early Holocene migrations of the marine polar front. LÄS MER
24. A palaeolimnological study of the anthropogenic impact on dissolved organic carbon in South Swedish lakes
Sammanfattning : During the past three decades, increases have been observed in dissolved organic carbon (DOC) concentrations and colour in the surface waters of lakes and rivers in parts of Europe and North America, raising concern about the effects on the quality of aquatic environments with consequences for biodiversity, resource availability and recreational use. Various hypotheses have been put forward to explain the recent increases in DOC concentration and numerous studies have been published linking them to declining anthropogenic atmospherically deposited sulphur. LÄS MER
25. Holocene development of Lake Lögurinn and Eyjabakkajökull : a multi-proxy approach
Sammanfattning : The North Atlantic region has experienced significant climate fluctuations during the Holocene. It has been shown that these fluctuations affected the terrestrial environment in Iceland, including its glaciers and ice caps. LÄS MER
