WorldCat Identities

Magnús Guðmundsson 1961-

Overview
Works: 12 works in 16 publications in 4 languages and 28 library holdings
Genres: Aerial photographs  Pictorial works  Illustrated works 
Roles: Author, Interviewee, Opponent
Publication Timeline
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Most widely held works by Magnús Guðmundsson
Land of light : photographs by Haukur Snorrason by Haukur Snorrason( Book )

3 editions published between 1999 and 2000 in English and held by 8 WorldCat member libraries worldwide

Experience Iceland( Book )

1 edition published in 2005 in Icelandic and held by 5 WorldCat member libraries worldwide

Hættumat vegna eldgosa og hlaupa frá vestanverðum Mýrdalsjökli og Eyjafjallajökli( Book )

2 editions published in 2005 in Icelandic and held by 4 WorldCat member libraries worldwide

The golden circle = Gullni hringurinn : Geysir, Gullfoss, Hekla, Kerið, Skálholt, Þingvellir, Reykjavík, Bláa Lónið by Magnús Guðmundsson( Book )

2 editions published between 2001 and 2006 in English and held by 2 WorldCat member libraries worldwide

Conclusion : recommendations and findings of the RED SEED working group( )

1 edition published in 2016 in English and held by 2 WorldCat member libraries worldwide

The crustal structure of the subglacial Grimsvötn volcano, Iceland, from multiparameter geophysical surveys by Magnús Guðmundsson( )

1 edition published in 1992 in English and held by 1 WorldCat member library worldwide

Fjallamennska by Ari Trausti Guðmundsson( Book )

1 edition published in 1983 in Icelandic and held by 1 WorldCat member library worldwide

Upplifðu Ísland( Book )

1 edition published in 2005 in Icelandic and held by 1 WorldCat member library worldwide

Ascension et dégazage des magmas basaltiques : application aux volcans d'Islande et de la Chaîne des Puys (France) by Baptiste Haddadi( )

1 edition published in 2016 in French and held by 1 WorldCat member library worldwide

Explosive basaltic eruptions are rare compared to effusive ones and the underlying physical mechanisms are poorly understood. The goal of this thesis is to study the causes of basaltic magma explosivity by characterizing the volcanic products of the subplinian eruption of trachy-basalt at the Puys de La Vache-Lassolas complex (Chaîne des Puys, France) and of phreatomagmatic and sub-plinian eruptions of tholeiitic magma at Grímsvötn volcano (Iceland). Minerals, matrix glasses and melt inclusions (Mis) were analysed with an electron microprobe to estimate volatile concentrations (initial and final), and pressure (P) and temperature (T) of crystallization using clinopyroxene-liquid thermobarometry. In addition, an experimental study was performed to better understand the limitations of clinopyroxeneliquid thermobarometry at moderate pressures and during magma ascent. Four eruptions were studied at Grímsvötn: two phreatomagmatic (AD1823 and AD2004) and two subplinian (AD1873 and AD2011). The subplinian eruptions have volatile concentrations higher than the phreatomagmatic ones, together with more efficient gas exsolution, leading to significantly higher atmospheric mass loading. Regardless of the eruptive regime, clinopyroxene-liquid (matrix glass or MI) equilibria in Grímsvötn magmas record the same depth of crystallization, namely ~15 km. This suggests that the shallow magma chamber of Grímsvötn plumbing system may only act as a reservoir in which gas exsolved from deeper origin is stored and accumulates between eruptions. The lower variability of clinopyroxene-MI equilibrium T in the 19th century eruptions, suggests important Grímsvötn magma system permeability following the Laki volcano-tectonic event end of 18th century. Average matrix glass-clinopyroxene equilibrium T decreases with time suggesting that Grímsvötn magma plumbing system as a whole may be slowly cooling over the last two centuries. Puys de La Vache-Lassolas products record a deeper magma contribution, from approximately 30 km depth. Initial volatile concentrations and ratios of the ~8.6 ka eruption are closer to those of arc magmas than to magmas from any other tectonic settings. This observation calls into a question the Chaîne des Puys hotspot hypothesis. The significant contribution of deep-derived magma is coherent with the crystallization of clinopyroxene contemporaneously with olivine. The Puys de La Vache-Lassolas eruption carried 0.5 Tg of HF, 0.7 Tg of HCl and 7.3 Tg of SO2 into the atmosphere illustrating the volcanic hazard to the Auvergne population. In order to better constrain petrological P-T estimations, a piston-cylinder experimental study of clinopyroxene stability in a tholeiitic magma (Holuhraun 2014-15, Iceland) was undertaken. The absence of olivine in the pressure range 0.5-1 GPa and the presence of clinopyroxene indicate that clinopyroxene is the first phase at the liquidus, confirming the importance of clinopyroxene-liquid thermobarometers when estimating P and T of crystallization of Icelandic tholeiitic magmas. Experiments in which P was decreased from 1 to 0.5 GPa and then kept constant show that equilibrium between clinopyroxene and liquid is still not reached after 24 hours at 0.5 GPa. Thus a residence time of several days at constant P and T is required to obtain reliable thermobarometric estimates
Landmótun og byggð í fimmtíu ár : loftmyndir úr safni Landmælinga Íslands = Fifty years of change and development : aerial photographs from Iceland by Þorvaldur Bragason( Book )

1 edition published in 1988 in Icelandic and held by 1 WorldCat member library worldwide

Vulkani določajo smer življenju : v objektivu Eyjafjallajökull by Blaž Mazi( )

1 edition published in 2010 in Slovenian and held by 1 WorldCat member library worldwide

 
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Alternative Names
Guðmundsson, Magnús

Guðmundsson, Magnús 1961-

Guðmundsson, Magnús Tumi 1961-

Magnús Guðmundsson, 1961-....

Magnús Tumi 1961

Magnús Tumi Guðmundsson 1961-

Magnús Tumi Guðmundsson hoogleraar uit IJsland

Magnús Tumi Guðmundsson Icelandic university teacher

Magnús Tumi Guðmundsson isländischer Geophysiker und Hochschullehrer

Languages