INTRODUCTION TO VOLCANOLOGY

CONTENTS

　1. Introduction
　2. Relationships of Volcanism and Plate Tectonics
　3. Magma Chamber and Physical Properties of Magma
　4. Explosive Types, Topography and Products of Volcanism
　5. Lava Flows and Domes
　6. Types and Mechanism of Pyroclastic Fragments
　7. Characteristics of Subaerial Eruption
　8. Characteristics of Hydrovolcanism
　9. Facies Analysis of Volcanic Products
　10.Volcanic Hazard
　11.Volcanism in Taiwan

VOLCANISM AND TECTONIC SETTINGS

　1. Mid-Oceanic Ridge Volcanism
　2. Back-Arc Basin Spreading Volcanism
　3. Intraplate Oceanic Volcanism
　4. Intraplate Continental Volcanism
　5. Continental Rift Volcanism
　6. Island Arc Volcanism
　7. Microcontinental Arc Volcanism
　8. Continental Margin Arc Volcanism

REFERENCES Chapter 15 in "Volcanic Succession", Edited by Cas, R.A.F. and Wright, J.Y. Chapter 14 in "Pyroclastic Rocks", Edited by Fisher, R.V. and Schmincke, H.-U. Gill, J.B. (1981) Orogenic Andesites and Plate Tectonics. Springer-Verlag, Berlin, Heidelberg, New York, 390p. Thorpe, R. S., ed. (1982) Andesites: Orogenic Andesites and Related Rocks. John Wiley and Son, New York, 724p.

MAGMA CHAMBER AND PHYSICAL PROPERTIES OF MAGMA

　I. Magma Chamber

　　A. Volume
　　B. Zonation
　　　a.Large Calcalkaline System-----Bishop Tuff
　　　b.Small Highly Alkalic System-----Laacher See Volcano
　　　c.Oceanic Rhyolite-Basalt System----Askja Volcano, Iceland
　　　d.Very Small Mafic-Intermediate Magma System
　　C.Detection
　　　a.Yellowstone Park
　　　b.Long Valley Caldera
　　　c.Hawaiian

　II. Physical Properties of Magma

　　A.Classification
　　B.Temperature
　　C.Density
　　D.Viscosity
　　　Factors Controlling Viscosity in Magma:
　　　a.Pressure
　　　b.Temperature
　　　c.Volatile Content
　　　d.Chemical Composition
　　　e.Crystal Content
　　　f.Bubble Content
　　E.Strength

REFERENCES Chapter 2 in "Volcanic Succession", Edited by Cas, R.A.F. and Wright, J.Y. Chapter 2&3 in "Pyroclastic Rocks", Edited by Fisher, R.V. and Schmincke, H.-U.

Explosive Types, Topography and Products of Volcanism

　1.Classification of volcanic eruption
　　A.Based on spatial relationship
　　　Central, Fissure and Areal Eruption
　　B.Based on products
　　　Magmatic, Phreatomagmatic and Phreatic Eruption
　　C.Based on violence
　　　(a)Lava Eruptions
　　　　Icelandic, Hawaiian and Viscous lava flows
　　　(b)Pyroclastic Eruptions
　　　　Strombolian, Vulcanean, Vesuvian, Pelean and Plinian
　　　(c)Walker's Classification
　　　(d)Explosion Index (E)
　　　 　E=tephra/tephra+lava
　　　(e)Volcanic Explosivity Index

　2.Types of Volcano
　　A.Basic lava volcanoes
　　B.Acidic lava volcanoes
　　C.Pyroclastic volcanoes
　　D.Mixed eruption volcanoes
　　E.Miscellaneous volcanoes

　3.Products of Eruption
　　A.Lava flows
　　B.pyroclastic deposits
　　C.Volcaniclastic deposits

REFERENCES Chapter 3 in "Volcanic Succession", Edited by Cas, R.A.F. and Wright, J.Y. Chapter 5 in "Pyroclastic Rocks", Edited by Fisher, R.V. and Schmincke, H.-U. Part 1 in "Volcanic Textures", Edited by McPhie, J., Doyle, M. and Allen, R.

Lava Flows and Domes

　1. Size and form of subaerial flows
　　Massive lava, Pahoehoe, Aa, Blocky lava
　2.Factoris affecting the morphology of subaerial lavas
　　a.Effusion rate
　　b.Physical properties
　　c.slope
　3.Eruption of basaltic lavas
　　a.Features of subaerial basaltic lava flows
　　　Pahoehoe and Aa lava, Flood basalt, Plains basalt
　　b.Features of submarine basaltic lava flows
　　c.Subaerial basaltic lavas flowing intto water
　4.Eruption of intermediate lavas
　5.Eruption of rhyolitic lavas

REFERENCES Chapter 4 in "Volcanic Succession", Edited by Cas, R.A.F. and Wright, J.Y. Chapter 5 in "Volcanoes", Edited by C. Ollier

Types and Mechanism of Pyroclastic Fragments

　1.Pyroclastic Fragments
　　A.Classification
　　B.Vitric particles and pyrogenic crystal
　　　a.Formation
　　　b.surface texture
　　C.Structures
　　　Planar, Cross, Graded, Massive beds
　2.Mechanism
　　A.Fragmentation due to magmatic eruption
　　　a.controling factor
　　　b.Explosive fragmentation from a seal,
　　　　near surface magma chamber or conduit
　　　c.Explosive fragmentation of a vesiculating
　　　　magma eruption from an open vent
　　　d.Magma mixing as a means of triggering explosive eruption
　　B.Fragmentation due to phreatic or steam explosions and 　　　
　　　phreatomagmatic eruption
　　C.Quench- or chill-shatter fragmentation
　　D.Flow fragmentation(autobrecciation)
　　E.Epiclastic fragmentation

REFERENCES Chapter 3 in "Volcanic Succession", Edited by Cas, R.A.F. and Wright, J.Y. Chapter 5 in "Pyroclastic Rocks", Edited by Fisher, R.V. and Schmincke, H.-U.

Characteristics of Subaerial Eruption

　1. Mechanism
　2. Evidences for subaerial eruption
　3. Three types of pyroclastic deposits
　4. Eruptions producing pyroclastic falls
　　A. Definition
　　B. Explosive eruption columns
　　C. Deposits
　5. Pyroclastic flow-forming eruptions
　　A. Definition
　　B. Lava-dome or lava flow collapse
　　C. Eruption column collapse
　　D. Deposits
　6. Origins of pyroclastic surges
　　A. Definition
　　B. Surges associated with phreatomagmatic and phreatic eruptions
　　C. Surges associated with flows
　　D. Deposits

REFERENCES Chapter 5 in "Volcanic Succession", Edited by Cas, R.A.F. and Wright, J.Y. Chapter 6 in "Pyroclastic Rocks", Edited by Fisher, R.V. and Schmincke, H.-U. Chapter 6and 7 in "Volcanoes", Edited by C. Ollier

Characteristics of Hydrovolcanism


　1. Hydrovolcanism
　　Definition and Characteristics
　2. Deep water stage
　3. Shoaling stage
　4. Transition submarine-subaerial
　5. Silicic subaqueous volcanism
　6. Subglacial volcanism

REFERENCES Chapter 9 in "Volcanic Succession", Edited by Cas, R.A.F. and Wright, J.Y. Chapter 9&10 in "Pyroclastic Rocks", Edited by Fisher, R.V. and Schmincke, H.-U.

Facies Analysis of Volcanic Products

　1. Introduction
　2. Factors affecting original lithological characteristics
　3. Facies as diagnostic indicators of paleoenvironments
　　a. pillow lava --- subaqueous
　　b. accretionary lapilli --- subaerial
　　c. ballistic bomb-sag structures --- near vent
　　d. eutaxitic texture --- subaerial
　　e. pink --- thermal alteration --- subaerial
　4. Lithofacies
　5. Volcanic facies(Association of facies)
　　a. facies based upon deposits of volcanism
　　b. facies based on position relative to source
　　c. facies based on environment of deposition
　　d. facies based on primary composition
　　e. diagenetic rock facies
　6. Facies models for volcanic succession
　　a. continental basaltic succession
　　b. continental stratovolcanoes
　　c. continental silicic volcanoes
　　d. submarine basaltic rift volcanism
　　e. oceanic basaltic seamounts
　　f. marine stratovolcanoes
　　g. submarine felsic volcanoes
　　h. deep marine facies derived fron shallow marine--aubaerial
　　　volcanic centers
　　i. interglacial basaltic and rhyolitic volcanism
　　j. precambrian volcanism

REFERENCES Chapter 14 in "Volcanic Succession", Edited by Cas, R.A.F. and Wright, J.Y. Chapter 13 in "Pyroclastic Rocks", Edited by Fisher, R.V. and Schmincke, H.-U.