Page 7 - Fundamentals of Physical Volcanology

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vi CONTENTS

4. Magma storage 43
4.1 Introduction 43
4.2 Evidence for magma storage within the crust 43
4.3 Formation and growth of magma chambers 53
4.4 Magma chambers and their impact on volcanic systems 58
4.5 Summary 62
4.6 Further reading 62
4.7 Questions to think about 63

5. The role of volatiles 64
5.1 Introduction 64
5.2 Volatiles in magma 64
5.3 The solubility of volatiles in magma 65
5.4 Bubble nucleation 67
5.5 Bubble growth 68
5.6 Magma fragmentation and the influence of volatiles on eruption styles 73
5.7 Summary 75
5.8 Further reading 76
5.9 Questions to think about 76

6. Steady explosive eruptions 77
6.1 Introduction 77
6.2 Influence of gas bubbles prior to magma fragmentation 77
6.3 Acceleration of the gas–magma mixture 78
6.4 Controls on exit velocity 80
6.5 Eruption plumes in steady eruptions 82
6.6 Fallout of clasts from eruption plumes 86
6.7 Unstable eruption columns 88
6.8 Summary 91
6.9 Further reading 92
6.10 Questions to think about 93

7. Transient volcanic eruptions 94
7.1 Introduction 94
7.2 Magmatic explosions 94
7.3 Transient eruptions involving external water 100
7.4 Summary 103
7.5 Further reading 104
7.6 Questions to think about 104

8. Pyroclastic falls and pyroclastic density currents 105
8.1 Introduction 105
8.2 Fallout of clasts from eruption columns 105
8.3 The application of eruption column models 110
8.4 Pyroclastic density currents and their deposits 115
8.5 Summary 121
8.6 Further reading 124
8.7 Questions to think about 125