Volcanology

  1. Magma: Generation, Composition, and Properties
    1. Magma Generation (Magmagenesis)
      1. Decompression Melting
        1. Occurrence at Mid-Ocean Ridges
          1. Adiabatic Decompression
            1. Mantle Upwelling
            2. Flux Melting
              1. Role of Water and Volatiles
                1. Subduction Zone Melting
                  1. Hydrous Minerals
                    1. Volatile Transfer
                    2. Heat Transfer Melting
                      1. Intrusion of Hot Magma
                        1. Contact Metamorphism
                          1. Crustal Anatexis
                        2. Magma Composition
                          1. Silicate Melts
                            1. Major Elements
                              1. Silicon (Si)
                                1. Aluminum (Al)
                                  1. Iron (Fe)
                                    1. Magnesium (Mg)
                                      1. Calcium (Ca)
                                        1. Sodium (Na)
                                          1. Potassium (K)
                                          2. Minor and Trace Elements
                                            1. Titanium (Ti)
                                              1. Phosphorus (P)
                                                1. Rare Earth Elements
                                                  1. Compatible vs. Incompatible Elements
                                                2. Classification by Silica Content
                                                  1. Basaltic (Mafic)
                                                    1. Mineralogy
                                                      1. Olivine
                                                        1. Pyroxene
                                                          1. Plagioclase
                                                          2. Typical Settings
                                                            1. Mid-Ocean Ridges
                                                              1. Hotspots
                                                                1. Continental Rifts
                                                              2. Andesitic (Intermediate)
                                                                1. Mineralogy
                                                                  1. Plagioclase
                                                                    1. Pyroxene
                                                                      1. Amphibole
                                                                      2. Typical Settings
                                                                        1. Subduction Zones
                                                                          1. Continental Arcs
                                                                        2. Dacitic
                                                                          1. Mineralogy
                                                                            1. Plagioclase
                                                                              1. Quartz
                                                                                1. Biotite
                                                                                  1. Hornblende
                                                                                  2. Typical Settings
                                                                                    1. Mature Continental Arcs
                                                                                      1. Crustal Melting
                                                                                    2. Rhyolitic (Felsic)
                                                                                      1. Mineralogy
                                                                                        1. Quartz
                                                                                          1. K-feldspar
                                                                                            1. Plagioclase
                                                                                              1. Biotite
                                                                                              2. Typical Settings
                                                                                                1. Continental Crust Melting
                                                                                                  1. Silicic Large Igneous Provinces
                                                                                            2. Physical Properties of Magma
                                                                                              1. Viscosity
                                                                                                1. Role of Silica Content
                                                                                                  1. Polymerization Effects
                                                                                                    1. Silica Tetrahedra Networks
                                                                                                    2. Role of Temperature
                                                                                                      1. Temperature-Viscosity Relationships
                                                                                                        1. Arrhenius Equation
                                                                                                        2. Effect of Volatiles
                                                                                                          1. Water Content
                                                                                                            1. Dissolved Gases
                                                                                                            2. Crystal Content Effects
                                                                                                            3. Gas Content (Volatiles)
                                                                                                              1. Water Vapor (H2O)
                                                                                                                1. Solubility in Magma
                                                                                                                  1. Pressure Dependence
                                                                                                                  2. Carbon Dioxide (CO2)
                                                                                                                    1. Solubility Limits
                                                                                                                      1. Early Exsolution
                                                                                                                      2. Sulfur Dioxide (SO2)
                                                                                                                        1. Oxidation State Effects
                                                                                                                          1. Environmental Impact
                                                                                                                          2. Other Gases
                                                                                                                            1. Hydrogen Sulfide (H2S)
                                                                                                                              1. Hydrogen Fluoride (HF)
                                                                                                                                1. Hydrogen Chloride (HCl)
                                                                                                                                  1. Noble Gases
                                                                                                                                2. Density
                                                                                                                                  1. Factors Affecting Density
                                                                                                                                    1. Temperature Effects
                                                                                                                                      1. Composition Effects
                                                                                                                                        1. Volatile Content
                                                                                                                                          1. Crystal Content
                                                                                                                                          2. Density Contrasts
                                                                                                                                          3. Temperature
                                                                                                                                            1. Temperature Ranges for Different Magmas
                                                                                                                                              1. Basaltic Temperatures
                                                                                                                                                1. Andesitic Temperatures
                                                                                                                                                  1. Rhyolitic Temperatures
                                                                                                                                                  2. Liquidus and Solidus
                                                                                                                                                    1. Crystallization Temperatures
                                                                                                                                                  3. Magma Evolution and Differentiation
                                                                                                                                                    1. Magma Chambers
                                                                                                                                                      1. Structure and Dynamics
                                                                                                                                                        1. Zoned Magma Chambers
                                                                                                                                                          1. Convection Patterns
                                                                                                                                                            1. Thermal Gradients
                                                                                                                                                            2. Magma Chamber Processes
                                                                                                                                                            3. Fractional Crystallization
                                                                                                                                                              1. Crystal Settling
                                                                                                                                                                1. Gravitational Settling
                                                                                                                                                                  1. Crystal Accumulation
                                                                                                                                                                  2. Compositional Changes
                                                                                                                                                                    1. Bowen's Reaction Series
                                                                                                                                                                      1. Liquid Line of Descent
                                                                                                                                                                      2. Cumulate Rocks
                                                                                                                                                                      3. Magma Mixing
                                                                                                                                                                        1. Processes and Evidence
                                                                                                                                                                          1. Mechanical Mixing
                                                                                                                                                                            1. Chemical Disequilibrium
                                                                                                                                                                              1. Textural Evidence
                                                                                                                                                                              2. Hybrid Magmas
                                                                                                                                                                              3. Assimilation of Crustal Rocks
                                                                                                                                                                                1. Contamination and Hybrid Magmas
                                                                                                                                                                                  1. AFC Processes
                                                                                                                                                                                    1. Isotopic Evidence

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                                                                                                                                                                                4. Volcanic Structures and Landforms