Explosion Pipes

ISBN-13: 9783642732607 / Angielski / Miękka / 2011 / 249 str.

Vladimir A. Milashev; R. E. Sorkina

Opis

Explosion pipes or diatremes are the result of magmatic gas eruptions. Their peculiar form, piercing contacts, various filling rocks and associated minerals attract the attention of geologists. In addition, they are economically profitable because many contain metalliferous mineralizations or, even more important, they are mined for diamonds. Scientific interest has focussed on the physical parameters such as dynamics, energy release, mechanisms responsible for the formation and filling of diatreme chambers. Geological conditions favorable for localizing explosion pipes are carefully considered. The study of different concepts has established potential guidelines for fields of diatremes: valleys of ancient and present drainage networks.

Spis treści

I Kimberlite and Lamproite Pipes.- 1 Morphology of Kimberlite Bodies.- Kimberlite Bodies: Major Types and Models.- Relationship Between Shape, Size of Bodies, Structural Features of Rocks and Depth of Erosion.- 2 Internal Structure of Kimberlite Bodies.- Endogenous Features.- Exogenous Features.- 3 Distribution of Xenoliths and Minerals in Kimberlite Pipes.- Distribution of Xenoliths.- Distribution of Diamond.- Distribution of Other Minerals.- 4 Contact Effects of Kimberlite.- Mechanical Effects.- Thermal and Chemical Effects.- 5 Size of Diatremes and Distribution of Bodies of Variable Sizes in Kimberlite Fields.- 6 Size of Diatremes and Genetic Features of the Rocks.- 7 Chronology of Kimberlite Formation.- Age of Kimberlite and Methods of its Determination.- Petrochemistry and Succession in Eruption of Kimberlite.- 8 Structural Control of Kimberlite Occurrence and Factors of its Localization.- Distribution and Tectonic Setting of Kimberlite.- Fissuring in Country Rocks and Structural Contacts of Kimberlite Fields.- Tectonic Factors Responsible for the Localization of Diatremes.- 9 Temporal and Spatial Rules in the Magmatic History of Kimberlite Fields.- 10 Kimberlite Magma Chambers.- The Hypotheses.- The Character and Number of Magma Chambers in Kimberlite Fields.- 11 Diatremes of Diamondiferous Lamproites of Australia.- Terminology.- Lamproite Geology.- Composition of Diamondiferous Lamproites.- Lamproites Versus Kimberlites.- II Nonkimberlite Diatremes.- 12 Alkali Basaltoid and Carbonatite Diatremes.- Anabar District.- Ingili District.- Onega Peninsula.- South Gissar.- Minusinsk District.- Mongolia.- ?eské St?edoho?i Mountains.- Northern Tanzania.- 13 Trap Formation Diatremes.- Angara-Ilim Province.- Minusinsk District.- 14 Trachyte Diatremes.- Kuonamka District.- Central Aldan District.- III Mechanism and Conditions of Pipe Formation.- 15 Hypotheses on the Genesis of Pipes.- 16 The Connection of Diatremes with the Earth’s Surface and Major Stages in Diatreme Formation.- 17 Physical State of the Material Involved in Diatreme Formation.- Temperature.- Pressure.- Viscosity, Density, and Phase State of the Matter.- 18 Dynamics and Mechanism of Pipe Formation.- Velocity of Ascending Flow of Mantle Material.- Thermomechanical Abrasion of Intruded Strata and the Formation of Diatreme Vents.- Dynamics of Diatreme Infilling and Formation of Major Genetic Rock Groups.- 19 Energetics and Geology of Processes Responsible for Pipe Formation.- Geothermal Energy Consumption by Diatreme Formation.- Sources and Probable Forms of Energy Conversion at the Time of Diatreme Formation.- Geological Setting Responsible for Energy Conversion and Regular Features of Diatreme Distribution.- Conclusions.- References.