Sökning: "tephra"
Visar resultat 1 - 5 av 14 uppsatser innehållade ordet tephra.
1. Baggalútar from Hvalfjörður (Iceland): Enigmatic spheroids of hydrothermally altered basaltic tephra
Kandidat-uppsats, Uppsala universitet/Mineralogi, petrologi och tektonikSammanfattning : Baggalútar are well-rounded spheroids that typically measures 16-18 mm in size and have a brownreddish appearance. They can be found in the Hvalfjörður bay in SW Iceland. LÄS MER
2. Reconstructing Past Climate by Grain Size and Magnetic Susceptibility Analysis of Belgium Loess From the Late Quaternary
Master-uppsats, Uppsala universitet/Institutionen för geovetenskaperSammanfattning : Aeolian dust that gets deposited builds up loess sequences that cover 10% of the Earth's continents. Such sequences can be several metres thick with material deposited over thousands of years, and therefore act like archives of past climates. LÄS MER
3. Diatoms from the late Holocene of the western Chukchi Sea, Arctic Ocean: environmental signals and palaeoceanography
Master-uppsats, Stockholms universitet/Institutionen för geologiska vetenskaperSammanfattning : The sediment Core SWERUS-L2-2-PC1 (2PC) retrieved from the Chukchi Sea, Arctic Ocean sits in an oceanographically dynamic location at the Arctic-Pacific Ocean gateway. The 8.3 m-long core was retrieved in Herald Canyon at the marginal ice zone at 57 m depth. LÄS MER
4. Assessing the late Holocene14C reservoir age of theChukchi Sea with the AniakchakCFE II tephra 3.6 kyr BP
Master-uppsats, Stockholms universitet/Institutionen för naturgeografiSammanfattning : Tephrochronology is a powerful tool to correlate and improve the chronology of sedimentaryarchives in the Arctic Ocean. The Aniakchak Caldera Forming Eruption (CFE) in Alaska at3.6 cal kyr BP ejected ash that were found in a widespread layer in Alaska, and as cryptotephrain the Chukchi Sea, Newfoundland, and Greenland. LÄS MER
5. Towards a Tephrochronology for the Lakselv Peat Sequence in Finnmark County, Northern Norway
Kandidat-uppsats, Stockholms universitet/Institutionen för naturgeografiSammanfattning : To provide an increased breadth in the knowledge of tephra dispersal, this pilot study examines a peat core from Lakselv in Finnmark County in northern Norway. Peat samples are exposed to burning, HCl, density separation and polarized light microscopy. One sample from a depth of 37.5-40 cm was analysed using an electron microprobe analyser (EMPA). LÄS MER