Volcano-Tectonic Processes

Foreword
Preface
Acknowledgements
Contents
About the Author
1 Volcanoes and Volcanic Activity
	1.1 Introduction
	1.2 The Volcano Factory
	1.3 Distribution of Volcanoes and Origin of Magmas
	1.4 Composition of Magmas
	1.5 Physical Properties of Melts and Magmas
	1.6 Types of Volcanic Edifices
	1.7 Volcanic Activity
	1.8 Effusive Eruptions and Their Products
	1.9 Explosive Eruptions and Their Products
	1.10 Volcanic Hazard and Risk
	1.11 What is Volcano-Tectonics?
	1.12 Summary
	1.13 Main Symbols Used
	References
2 Crustal Deformation
	2.1 Introduction
	2.2 Stress
	2.3 Deformation
	2.4 Rheology of Rocks
		2.4.1 Elastic Deformation
		2.4.2 Plastic Deformation
		2.4.3 Viscous Deformation
		2.4.4 Combined Deformation Models
		2.4.5 The Role of the Boundary Conditions
		2.4.6 Rheology of the Crust and Magma
	2.5 Brittle Deformation
		2.5.1 Extension Fractures
		2.5.2 Shear Fractures
	2.6 Faults
	2.7 Tectonic Regimes
		2.7.1 Extensional Tectonics
		2.7.2 Contractional Tectonics
		2.7.3 Strike-Slip Tectonics
	2.8 Summary
	2.9 Main Symbols Used
	References
3 The Rise of Magma Through the Crust
	3.1 Introduction
	3.2 Magmatic Diapirs
		3.2.1 Diapir Initiation
		3.2.2 Diapir Rise
		3.2.3 Diapir Emplacement
		3.2.4 Diapirism and Stoping
		3.2.5 Limitations of Diapirism as a Mechanism for Magma Transport
	3.3 Magma-Filled Fractures
	3.4 Dike Propagation
		3.4.1 Solid Mechanics
		3.4.2 Fluid Mechanics
		3.4.3 Thermal Constrains
		3.4.4 Seismicity Constraints
	3.5 Dike Arrest
	3.6 Summary
	3.7 Main Symbols Used
	References
4 Magma Emplacement and Accumulation: From Sills to Magma Chambers
	4.1 Introduction
	4.2 General Features
	4.3 Sills
		4.3.1 Overview
		4.3.2 Emplacement Conditions
	4.4 Laccoliths, Bysmaliths and Lopoliths
		4.4.1 Overview
		4.4.2 Emplacement Conditions
	4.5 Plutons
		4.5.1 Overview
		4.5.2 Tectonically-Assisted Plutons
		4.5.3 Magma-Induced Plutons
	4.6 Magma chambers and magma reservoirs
		4.6.1 Overview
		4.6.2 Development Conditions
		4.6.3 Magma Chambers Attracting and Nucleating Dikes
	4.7 The Plutonic-Volcanic Link
	4.8 Summary
	4.9 Main Symbols Used
	References
5 Calderas
	5.1 Introduction
	5.2 General Features of Calderas
	5.3 Structure and Evolution
	5.4 Classification
	5.5 Relationships to Regional Tectonics
	5.6 Resurgence
	5.7 Caldera Unrest
	5.8 Long- Versus Short-Term Deformation
	5.9 Magma Transfer and Eruptions
	5.10 Lessons from Active Calderas
		5.10.1 Sierra Negra
		5.10.2 Rabaul
		5.10.3 Recent Caldera Collapses
	5.11 Summary
	5.12 Main Symbols Used
	References
6 Volcano Flank Instability and Collapse
	6.1 Introduction
	6.2 General Features
	6.3 Anatomy of an Unstable Flank
	6.4 Causes of Flank Instability and Collapse
		6.4.1 Magma Emplacement (Dikes and Viscous Intrusions)
		6.4.2 Hydrothermal Alteration
		6.4.3 Excess Pore Pressures
		6.4.4 Weak Layers and Basement (Volcano Spreading)
		6.4.5 Fault Activation and Earthquakes
		6.4.6 Weather and Climate
	6.5 Analysis of Flank Instability
	6.6 Sector Collapse and Eruptive Activity
	6.7 Multi-hazards Related to Flank Instability and Collapse
	6.8 Lessons from Unstable Volcanoes
		6.8.1 Mount Etna
		6.8.2 Mount St. Helens
		6.8.3 Augustine
	6.9 Summary
	6.10 Main Symbols Used
	References
7 Shallow Magma Transfer
	7.1 Introduction
	7.2 Overview
	7.3 Regional Dikes
	7.4 Magma Transfer Through Sills
	7.5 Circumferential Intrusions
		7.5.1 Circumferential Eruptive Fissures
		7.5.2 Cone Sheets
		7.5.3 Ring-Dikes
	7.6 Radial Dikes
		7.6.1 Radial Dikes in Conical Volcanic Edifices
		7.6.2 Radial Dikes in Conical Edifices with Sector Collapse
		7.6.3 Radial Dikes in Elongated Edifices
	7.7 Dikes Reaching the Surface
	7.8 Summary
	7.9 Main Symbols Used
	References
8 Volcano Monitoring
	8.1 Introduction
	8.2 General Features
	8.3 Deformation Monitoring
		8.3.1 Deformation Monitoring Techniques
		8.3.2 Deformation Source Models
		8.3.3 Deformation Forecasting Potential
	8.4 Geophysical Monitoring
		8.4.1 Monitoring Volcano Seismicity
		8.4.2 Monitoring Volcano Gravity
	8.5 Geochemical Monitoring
	8.6 Summary
	8.7 Main Symbols Used
	References
9 Unrest and Eruption Forecasting
	9.1 Introduction
	9.2 General Features
	9.3 Unrest Triggers
		9.3.1 Magmatic Trigger
		9.3.2 Hydrothermal Trigger
		9.3.3 Seismic Trigger
	9.4 Understanding Unrest
	9.5 Assessing Volcanic Hazard and Forecasting Eruptions
	9.6 Deterministic Forecasting
	9.7 Probabilistic Forecasting
		9.7.1 Long-Term Forecasting
		9.7.2 Short-Term Forecasting
	9.8 Summary
	9.9 Main Symbols Used
	References
10 Volcanoes and Plate Tectonics
	10.1 Introduction
	10.2 The Plate Tectonics Frame
	10.3 Magmatic Processes Along Divergent Plate Boundaries
	10.4 Magmatic Processes Along Convergent Plate Boundaries
	10.5 Magmatic Processes at Hot Spots
	10.6 Polygenic and Monogenic Volcanism
	10.7 Magma Versus Regional Tectonics
	10.8 Summary
	10.9 Main Symbols Used
	References
11 Volcanoes at Divergent Plate Boundaries
	11.1 Introduction
	11.2 Continental Rifts: The East African Rift System
		11.2.1 The Main Ethiopian Rift
	11.3 Transitional Rifts: Afar
	11.4 Oceanic Rifts
		11.4.1 Ultraslow Ridges: The Red Sea and the Southwest Indian Ridge
		11.4.2 Slow Ridges: The Icelandic Ridge
		11.4.3 Fast and Ultrafast Ridges: The East Pacific Rise
	11.5 A General Model for Divergent Plate Boundaries
	11.6 Summary
	11.7 Main Symbols Used
	References
12 Volcanoes Along Convergent Plate Boundaries
	12.1 Introduction
	12.2 Extensional Arcs
		12.2.1 Cascade Arc
		12.2.2 Taupo Volcanic Zone of New Zealand
		12.2.3 Tyrrhenian Margin of Central Italy
	12.3 Strike-Slip Arcs
		12.3.1 The South Andean Volcanic Zone
		12.3.2 Sumatra, Indonesia
	12.4 Contractional Arcs
		12.4.1 Northeast Honshu, Japan
		12.4.2 The Central Andes
	12.5 A Synthetic Model for Convergent Plate Boundaries
	12.6 Summary
	References
13 Hot Spots
	13.1 Introduction
	13.2 Hawaii Hot Spot
	13.3 Galapagos Hot Spot
	13.4 Easter Island Hot Spot
	13.5 Reunion Hot Spot
	13.6 Canary Islands Hot Spot
	13.7 Azores Hot Spot
	13.8 Yellowstone Hot Spot
	13.9 Tibesti Hot Spot
	13.10 Comparing Hot Spot Volcanoes
	13.11 Summary
	References
Index