Sökning: "felsic"

Visar resultat 1 - 5 av 26 uppsatser innehållade ordet felsic.

  1. 1. Origin of Silicic Magmatism at the Katla Volcano, South Iceland

    Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

    Författare :Caroline Svanholm; [2021]
    Nyckelord :Katla volcano; Iceland; high-silica rocks; oxygen isotopes; AFC processes; Vulkanen Katla; Island; kiselrika bergarter; syreisotoper; AFC-processer;

    Sammanfattning : Katla volcano, South Iceland, is a bimodal volcanic system hosting an unusual high number of silicic rocks within a basaltic rift setting. The petrogenesis of silica-rich rocks at Katla is controversial and two end-member hypotheses have been suggested. LÄS MER

  3. 2. Kinetic interpretation of microstructures in the Gällivare area; implications for deformation phases and related metamorphic events.

    Kandidat-uppsats, Luleå tekniska universitet/Institutionen för samhällsbyggnad och naturresurser

    Författare :Linnéa Jansson Fagerlund; [2021]
    Nyckelord :Geology; Northern Sweden; Gällivare; Nautanen Deformation Zone; Fjällåsen Deformation Zone; Microstructures;

    Sammanfattning : The goal of this study was to identify and describe different microstructures observed in samples from two major shear zones in the Gällivare area, namely the Nautanen Deformation Zone (NDZ), and the Fjällåsen deformation zone (FDZ). Thirteen samples were examined during this study. LÄS MER

  4. 3. Volcanic facies and hydrothermal alteration at the Norra volcanigenic massive sulfide deposit : Storuman area, Sweden

    Master-uppsats, Luleå tekniska universitet/Institutionen för samhällsbyggnad och naturresurser

    Författare :Meseret Gebreyesus; [2020]
    Nyckelord :Volcanic massive sulfide deposit; alteration zonation; volcanic chemostratigraphy; facies architecture;

    Sammanfattning : The Skellefte District, with a long and rich history of base metal extraction that commenced asearly as 1924, is rated amongst the leading mining provinces in Sweden and Europe. The districtrepresents a Paleoproterozoic volcanic arc hosting more than 85 known (gold-bearing) VMSdeposits and several economic grade orogenic gold occurrences. LÄS MER

  5. 4. Petrography, alteration and structure of the Bronäs Zn-Pb-Ag deposits, Bergslagen, Sweden

    Master-uppsats, Luleå tekniska universitet/Institutionen för samhällsbyggnad och naturresurser

    Författare :Tom Turner; [2020]
    Nyckelord :Bronäs; Sala;

    Sammanfattning : This report aims to characterize the alteration styles and mineralization of the Zn-Pb-Ag Bronäs deposit, in the Sala area of the Bergslagen mining district, Sweden.  It presents data collected through 237m of lithological logging and subsequent lithogeochemical data, which, coupled with thin section and SEM analysis has led to the first geological descriptions of the rocks in the deposit. LÄS MER

  7. 5. Implications of Magma and Bedrock Interaction, a Study of Xenopumice from La Palma, the Canary Islands

    Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

    Författare :Beatrice Jägerup; [2019]
    Nyckelord :La Palma; xenopumice; phreatomagmatism; whole rock geochemistry; oxygen isotopes; La Palma; felsiska xenoliter; explosiv vulkanism; geokemi; syreisotoper;

    Sammanfattning : This thesis focuses on frothy, felsic xenoliths called ‘xenopumice’, that were retrieved from La Palma during a 10–day field campaign in December 2018. There are only few descriptions of these frothty xenoliths, and a consensus on their origin has not yet been achieved. LÄS MER