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1. 1. Early Palaeozoic jawed polychaetes with focus on polychaetaspids and ramphoprionids from the Silurian of Gotland, Sweden

   Författare :Mats Eriksson; Berggrundsgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fysisk geografi; Geologi; physical geography; Geology; chemistry; palaeobiogeography; palaeoecology; taxonomy; apparatus reconstructions; Silurian; Recent; Ordovician; early Palaeozoic; scolecodonts; Annelida; polychaeta;

   Sammanfattning : Jawed polychaete annelid worms were abundant and diverse in the early Palaeozoic seas and their jaws (scolecodonts) are common microfossils in sedimentary rocks of that age. Despite their abundance, relatively little work has been focused on these fossils. LÄS MER

3. 2. Nanomagnetic and Micromagnetic Properties of Rocks Minerals and Sulphide Oxidation Products

   Författare :Erik Eneroth; Berggrundsgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; physical geography; Geology; multi-domain; single-domain; ilmenite; magnetite; maghemite; hematite; pyrite; marcasite; fysisk geografi; Geologi;

   Sammanfattning : Magnetic and related properties of rocks and products from oxidation of sulphide minerals have been investigated with magnetisation measurements (rocks and oxidation products), magnetic force microscopy (rocks), scanning electron microscopy (rocks and oxidation products), transmission electron microscopy (oxidation products), Mössbauer spectroscopy (oxidation products) and powder X-ray diffraction (oxidation products). The investigations have shown the following: During thermal oxidation of pyrite (cubic FeS2) and marcasite (orthorombic FeS2) in air, nano-crystals of a-Fe2O3 and g-Fe2O3 were formed. LÄS MER

4. 3. Assessing the reliability of detrital zircon in Early-Earth provenance studies

   Författare :Ross Kielman; Martin Whitehouse; Alexander Nemchin; Victoria Pease; Marlina Elburg; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Geology; geologi;

   Sammanfattning : Our understanding of the Early Earth and the processes that have shaped its evolution have spawned predominantly from the geochemical and isotopic signatures of a small number of zircon populations around the world. Studies of trace element distributions, Hf and O isotope systematics as well as mineral inclusion chemistry in detrital zircon are combined with U-Pb chronology in order to constrain source rock characteristics. LÄS MER

5. 4. Vegetation and land-use in the Småland Uplands, southern Sweden, during the last 6000 years

   Författare :Per Lagerås; Kvartärgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geologi; physical geography; Sweden; Geology; Småland Uplands; land-use history; pollen analysis; Holocene vegetation history; mineral magnetic analysis; AMS dating; clearance cairns; hay production; shifting cultivation; Picea migration; slash-and-burn cultivation; fysisk geografi;

   Sammanfattning : Palaeoecological methods were applied to peat and sediment cores recovered from one bog (Bråtamossen) and two lakes (Avegöl and Femtingagölen) in the Småland Uplands, southern Sweden. The general aim was to reconstruct the landuse and vegetation history for the last 6000 years in this agriculturally marginal region. LÄS MER

7. 5. The lower and middle Cambrian of Sweden: trilobites, biostratigraphy and intercontinental correlation

   Författare :Niklas Axheimer; Berggrundsgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sedimentologi; Paleontologi; Palaeontology; fysisk geografi; Geologi; physical geography; Geology; Sweden; correlation; trilobites; biostratigraphy; Cambrian; Sedimentology;

   Sammanfattning : This thesis is based on studies of Cambrian successions in Sweden, with particular focus on the middle Cambrian biostratigraphy and its correlative relationship to the proposed global agnostoid zonation. The investigated material, mainly trilobites, was collected from both outcrops and drill cores from five provinces in Sweden: Skåne (Scania), Öland, Västergötland, Jämtland and Lapland. LÄS MER