Centrifuge experiments with magmatic systems [Elektronische Ressource] : from melt segregation to pluton emplacement / von Mélanie Forien

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Informations

• Publié par: goethe_universitat_frankfurt_am_main
• Publié le: 01 janvier 2011
• Nombre de lectures: 34
• Langue: English
• Poids de l'ouvrage: 9 Mo

Extrait

Centrifuge experiments with magmatic systems: from melt segregation
to pluton emplacement



Dissertation
zur Erlangung des Doktorgrades
der Geowissenschaften


vorgelegt beim Facheinheit Geophysik
der Johann Wolfgang Goethe-Universität
in Frankfurt am Main


von
Mélanie Forien
aus Gien (Frankreich)




Frankfurt am Main, den 25 März 2011
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vom Fachbereich Geowissenschaften der
Johann Wolfgang Goethe - Universität als Dissertation angenommen.

Dekan: Prof. Dr. R. Pütz

Gutachter :
1. Prof. Dr. H. Schmeling
2. Prof. Dr. J-L. Vigneresse
3. PD. Dr. N. Bagdassarov

Datum der Disputation : 25 März 2011
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"[...] la géologie expérimentale a enfin reçu définitivement droit de cité dans la science.
Son but, comme on le sait, est d'imiter, par les procédés du laboratoire, les phénomènes
géologiques et les produits variés qu'ils ont engendrés dans les diverses régions de
l'écorce terrestre. Une foule de problèmes ont déjà été élucidés par son intervention
toute-puissante et l'on doit attendre les plus grands progrès de son complet
développement."

Stanislas MEUNIER (1843-1925)
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Table of contents


ACKNOWLEDGMENTS .................................................................................... 9
ABSTRACT...................................................................................................... 11
ABSTRAKT...................................................................................................... 17
RÉSUMÉ.......................................................................................................... 22
INTRODUCTION.............................................................................................. 25
CHAPTER I - PRINCIPLES AND METHODS.................................................. 31
I.1 - PRINCIPLES OF THE MODELING................................................................... 33
I.1.1 - Centripetal and centrifugal force ..................................................... 33
I.1.2 - Sedimentation principle................................................................... 35
I. 2 - CENTRIFUGES ......................................................................................... 36
I.2.1 - How a centrifuge works technically ................................................. 36
I.2.2 - Centrifuge used in this study........................................................... 38
CHAPTER II - PLUTON EMPLACEMENT: THE NESTED DIAPIRS. ............. 41
II.1 - INTRODUCTION ........................................................................................ 43
II.2 - EXPERIMENTAL PROCEDURE..................................................................... 44
II.2.1 - Set-up of experiment 1 - without initial perturbations ..................... 45
II.2.2 - Set-up of experiment 2................................................................... 45
II.2.3 - Set-up of experiment 3................................................................... 46
II.2.4 - Set-up of experiment 4................................................................... 47
II.2.5 - Set-up of experiment 5................................................................... 47
II.3 - EXPERIMENTAL RUN AND RESULTS OF THE EXPERIMENTS............................ 48
II.3.1 - Experiment 1 - without initial perturbations .................................... 48
II.3.2 - Experiment 2.................................................................................. 49
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II.3.3 - Experiment 3.................................................................................. 49
II.3.4 - Experiment 4.................................................................................. 52
II.3.5 - Experiment 5.................................................................................. 55
II.4 - SUMMARY............................................................................................... 55
CHAPTER III - THE SETTLING AND COMPACTION OF OLIVINE................ 59
III.1 - INTRODUCTION ....................................................................................... 61
III.2 - EXPERIMENTAL AND ANALYTICAL TECHNIQUES .......................................... 61
III.2.1 - Experimental strategy ................................................................... 61
III.2.2 - Experimental techniques............................................................... 61
III.2.3 - Analytical techniques .................................................................... 63
III.3 - RESULTS ............................................................................................... 65
III.3.1 - Crystal distribution after static annealing....................................... 65
III.3.2 - Porosity profiles through the olivine layer...................................... 65
III.3.3 - Grain growth ................................................................................. 72
CHAPTER IV - CRYSTAL - MELT SETTLING IN A MAGMA CHAMBER...... 79
IV.1 - INTRODUCTION....................................................................................... 81
IV.2 – CENTRIFUGE EXPERIMENTS.................................................................... 81
IV.2.1 – Centrifuge furnace ....................................................................... 81
IV.2.2 - Sample preparation ...................................................................... 82
IV.2.3 - Analytical methods........................................................................ 82
IV.2.4 - Results.......................................................................................... 83
IV.3 - NUMERICAL SIMULATION ......................................................................... 89
IV.3.1 - General description....................................................................... 89
IV.3.2 - Mathematical model...................................................................... 91
IV.3.3 - Input parameters........................................................................... 93
IV.3.4. Results........................................................................................... 94

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CHAPTER V - DISCUSSION ........................................................................... 99
V.2 – EMPLACEMENT OF NESTED DIAPIRS........................................................ 101
V.3 – ORTHO- AND ADCUMULATE TIME FORMATION .......................................... 104
V.3.1 - Settling velocity in olivine cumulate ............................................. 104
V.3.2 - Pressure dissolution and precipitation - chemical compaction..... 106
V.3.3 - Formation times of gravitational cumulates in layered intrusions. 109
V.4 - CRYSTAL SETTLING-FLOATING PROCESS IN A MAGMA CHAMBER................. 112
V.4.1 - Structure of centrifuge samples ................................................... 113
V.4.2 - Compositional trends of the major and trace elements
concentrations in the glass layer 1. ......................................................... 114
V.4.3 - Evolution of the compaction......................................................... 115
V.5 - COMPARISON WITH NATURAL EXAMPLES.................................................. 116
V.5.1 - The Great Kavir ........................................................................... 116
V.5.2 - The Odenwald Crystalline Complex............................................. 116
V.5.3 - The Muskox intrusion................................................................... 117
CONCLUSION ............................................................................................... 123
REFERENCES............................................................................................... 129
LEBENSLAUF ............................................................................................... 147


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Acknowledgments

I am pleased to thank my PhD supervisors, Nick Bagdassarov and Carlo Dietl,
for their patience, their scientific rigor and their help. Moreover, they have given me full
freedom and support during the course of my research work, for which I am thankful.
That allowed to me to have an autonomy that I have lot of appreciated during my thesis.
I would also like to associate in this acknowledgement, Max Schmidt from ETH
Zürich, as well as, Hemin Koyi from Uppsala University to have given me a warm
welcome in their respective laboratories. I enjoyed create new contacts, at during these
research works, with Paula Ardia, Remco Hin, Lukas Martin, Luca Caricchi , Marion
Louvel, Jessica Langlade, Mattia Pistone, and Steffi Burchardt. It was a pleasure to
work with these people and to benefit from their knowledge.
Although I have not h