An investigation into the explosivity of shallow subaqueous basaltic eruptions

Surtseyan eruption;Basalt;MFCI;Vesicle micro-texture;Vesicle number density;Volcanic ash

Murtagh, Rachel Maria ; White, James D.L.

University of Otago

关键词: Surtseyan eruption;    Basalt;    MFCI;    Vesicle micro-texture;    Vesicle number density;    Volcanic ash;   

Others  :  https://ourarchive.otago.ac.nz/bitstream/10523/1982/4/MurtaghRachel2011PhD.pdf

美国|英语

来源: Otago University Research Archive

【 摘 要 】

Explosive basaltic eruptions present a challenge to modelling volcanic behaviour. The main focus of this thesis is the examination of pyroclastic micro-textures and morphology of the ash fraction in order to constrain the conduit conditions during ascent and at the time of fragmentation, respectively in the lead up to such explosive volcanic eruptions. Three sites, Black Point, California, Pahvant Butte, Utah and Ilchulbong, Korea, were considered. I propose that, in certain cases, conduit processes can collaborate to modify basaltic magma rheology, which can be complemented by powerful water-magma interactions to result in an intense and violent eruption.Results of micro-textural data show: (1) vesicularity of shallow subaqueous basaltic (;;Surtseyan