Search for dissertations about: "Large Igneous Province"

Found 3 swedish dissertations containing the words Large Igneous Province.

  2. 1. New constraints on paleoreconstructions through geochronology of mafic dyke swarms in North Atlantic Craton

    Author : Mimmi Nilsson; Berggrundsgeologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; baddeleyit; U-Pb; geokronologi; large igneous province; mantelplym; superkontinent; paleorekonstruktion; North Atlantic craton; baddeleyite; Large Igneous Province; Mantle plume; supercontinent; paleoreconstruction; U-Pb; geochronology; North Atlantic craton;

    Abstract : Earth history is punctuated by a series of events of supercontinent amalgamation and break-up. Fragments of old continents display rifted margins and orogenic sutures that testify their involvement in supercontinent cycles. READ MORE

  4. 2. Validating the existence of the supercraton Vaalbara in the Mesoarchaean to Palaeoproterozoic

    Author : Ashley Gumsley; Berggrundsgeologi; []
    Keywords : Vaalbara; Kaapvaal Craton; Pilbara Craton; U-Pb geochronology; paleomagnetism; supercontinent; large igneous province; dyke swarm; sill province;

    Abstract : In this thesis, the longevity and continuity of the Vaalbara supercraton is addressed in six papers aimed at placing new temporal and spatial constraints onthe supercraton in the Mesoarchean to Paleoproterozoic. It has been speculated since the 1960’s that the Kaapvaal Craton in southern Africa, together withthe Pilbara Craton in Western Australia existed as a single landmass during the Precambrian – the Vaalbara supercraton. READ MORE

  5. 3. U-Pb baddeleyite geochronology of Precambrian mafic dyke swarms and complexes in southern Africa - regional scale extensional events and the origin of the Bushveld Complex

    Author : Johan Olsson; Berggrundsgeologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; U-Pb TIMS geochronology; geochemistry; baddeleyite; mafic dyke swarms; mantle plume; Bushveld Complex; Kaapvaal Craton; Zimbabwe Craton; Archean; Proterozoic;

    Abstract : Dolerite dykes are formed when iron- and magnesium-rich (mafic) mantle-derived magmas ascend through the lithosphere (upper part of the mantle) and crystallize as ‘hydro-fractures’ within the crust. Dykes may exist in great numbers to form dyke swarms (linear or radiating), which can be linked to time periods of continental break-up, or attempted break-up events, associated with voluminous volcanism. READ MORE