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Magma Mixing Interaction Between Rhyolitic and Basaltic Melt Magma Mixing Interaction Between Rhyolitic and Basaltic Melt Daniele Morgavi München 2013 Magma Mixing Interaction Between Rhyolitic and Basaltic Melts Daniele Morgavi Dissertation an der Fakultat fur Geowissenschaften der Ludwig-Maximilians-Universität München vorgelegt von Daniele Morgavi aus Roma, Italia München, den May, 2013 Erstgutachter: DONALD B. DINGWELL Zweitgutachter: DIEGO PERUGINI Tag der mündlichen Prüfung: 14. 01. 2014 To all the Friend and lovers that have shared a peace of their life with me In my life (Lennon and McCartney) There are places I remember All my life, though some have changed Some forever not for better Some have gone and some remain All these places have their moments With lovers and friends I still can recall Some are dead and some are living In my life I've loved them all But of all these friends and lovers There is no one compares with you And these memories lose their meaning When I think of love as something new Though I know I'll never lose affection For people and things that went before I know I'll often stop and think about them In my life I love you more Though I know I'll never lose affection For people and things that went before I know I'll often stop and think about them In my life I love you more In my life I love you more i Table of content Table of content……………………………………………………………………ii List of figures………………………………………………………………………iv List of tables………………………………………………………………………..v Preamble…………………………………………………………………………...vi Summary…………………………………………………………………………..vii Zusammenfassung………………………………………………………………...viii Chapter 1. Introduction…………………………………………………………….1 1.1 Magma mixing theory the idea of Bunsen…………………………………2 1.2 Magma mixing in the modern times……………………………………….4 1.3 Numerical and experimental stady a new light for understanding magma mixing………………………………………………………………5 1.4 Chaotic Mixing Experiment………………………………………………..6 Chapter 2. INTERACTION BETWEEN RHYOLITIC AND BASALTIC MELTS UNRAVELED BY CHAOTIC MIXING EXPERIMENTS……………………...8 Summary……………………………………………………………………..…..9 2.1. Introduction ...................................................................................................10 2.2 End-members and experimental setup..........................................................11 2.2.1 End-member selection and preparation ....................................................11 2.2.2 Chaotic mixing experiments........................................................................12 2.2.3 Analytical methods.......................................................................................16 2.3 Results ..............................................................................................................18 2.3.1 Optical analysis.............................................................................................18 2.3.2 Geochemical variations................................................................................20 2.4. Concentration variance analysis...................................................................28 2.5. Discussion........................................................................................................34 2.6. Conclusions and outlook................................................................................37 Chapter 3. TIME EVOLUTION OF CHEMICAL EXCHANGES DURING MIXING OF RHYOLITC AND BASALTIC MELTS…………………………………………..39 Summary…………………………………………………………………...…….40 3.1. Introduction....................................................................................................41 3.2. End-members and experimental setup........................................................42 3.2.1 End-member selection and preparation....................................................42 3.2.2 Experiments.................................................................................................43 3.2.3 Analytical methods......................................................................................47 3.3. Results.............................................................................................................47 3.3.1 Optical analysis............................................................................................47 3.3.2 Geochemical variations...............................................................................48 3.4. Discussion.......................................................................................................53 3.4.1. Validation of the two end-member mixing model...................................53 3.4.2 Quantification of element mobility during mixing...................................58 3.4.3 Causes of the differential mobility of chemical elements during mixing................................................................................................63 3.4.4. Relative mobility of chemical elements in time conclusion and outlook.................................................................................67 ii Chapter 4. MORPHOCHEMISTRY OF PATTERNS PRODUCED BY MIXING OF RHYOLITIC AND BASALTIC MELTS…………………………………………72 Summary…………………………………………………………………………73 4.1. Introduction…………………………………………………………………74 4.2. Magma mixing experiments………………………………………………..76 4.2.1 End-member selection and preparation………………………………….76 4.2.2 Experiments………………………………………………………………..77 4.3. Analysis of mixing patterns………………………………………………...79 4.3.1 Optical analysis…………………………………………………………….79 4.3.2 Geochemical analysis……………………………………………………....80 4.3.3 Fractal analysis of mixing patterns……………………………………….84 4.4. Discussion……………………………………………………………………87 4.5. Conclusions and Outlook…………………………………………………...92 Chapter 5.……………….…………………………………………………………...95 5.1 Outlook……………………………………………………………………….96 5.2 Acknoledgements...…..………………………………………………………98 5.3 References……...……...……………………………………………………..100 iii List of Figures Chapter 1. Introduction Figure 1…………………………………………………………………………….2 Chapter 2. INTERACTION BETWEEN RHYOLITIC AND BASALTIC MELTS UNRAVELED BY CHAOTIC MIXING EXPERIMENTS Figure 1......................................................................................................................13 Figure 2 .....................................................................................................................15 Figure 3 .....................................................................................................................17 Figure 4. ....................................................................................................................19 Figure 5. ....................................................................................................................21 Figure 6. ....................................................................................................................23 Figure 7......................................................................................................................24 Figure 8......................................................................................................................26 Figure 9......................................................................................................................27 Figure 10....................................................................................................................29 Figure 11....................................................................................................................30 Figure 12....................................................................................................................31 Figure 13....................................................................................................................33 Chapter 3. TIME EVOLUTION OF CHEMICAL EXCHANGES DURING MIXING OF RHYOLITC AND BASALTIC MELTS Figure 1. ..................................................................................................................44 Figure 2 ....................................................................................................................46 Figure 3 ...................................................................................................................49 Figure 4.....................................................................................................................50 Figure 5.....................................................................................................................51 Figure 6.....................................................................................................................52 Figure 7.....................................................................................................................55 Figure 8.....................................................................................................................57 Figure 9.....................................................................................................................60 Figure 10...................................................................................................................61 Figure 11...................................................................................................................63 Figure 12...................................................................................................................68 Chapter 4. MORPHOCHEMISTRY OF PATTERNS PRODUCED BY MIXING OF RHYOLITIC AND BASALTIC MELTS Figure 1. ...................................................................................................................77 Figure 2 ....................................................................................................................79
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