7.4 Regional Metamorphism As described above, regional metamorphism occurs when rocks are buried deep in the crust. Despite considerable regional deformation, this particular outcrop remained almost undeformed, and retains intact igneous textures. These can range from textures similar to the original protolith at low grades of metamorphism, to textures that are purely produced during metamorphism and leave the rock with little resemblance to the original protolith. This alteration increased the size of the mineral grains and segregated them into bands, a transformation which made the rock and its … Textures and Structures of Metamorphic Rocks 1. Gneiss usually forms by regional metamorphism at convergent plate boundaries. Metamorphic Textures provides definitions, descriptions and illustrations of metamorphic textures, as well as the fundamental processes involved in textural development.This book is composed of 11 chapters and begins with a presentation of the metamorphic processes and the production of metamorphic … Regional metamorphism results in intense alteration of the mineralogy and texture of rocks, usually to the point where original sedimentary structures are destroyed. Regional metamorphism occurs because both pressure and temperature increase with depth in Earth (Figure 8.3). This kind of metamorphism, called regional metamorphism, creates large metamorphic terranes, regions characterized by distinctive metamorphic rocks and intensity of metamorphism that may vary laterally. This book will be of great use to petrologists, physicists, and graduate and undergraduate petrology students. These are said to have a poikioblastic texture. Regional metamorphism is associated with the major events of Earth dynamics, and the vast majority of metamorphic rocks are so produced.They are the rocks involved in the cyclic processes of erosion, sedimentation, burial, metamorphism, and mountain building (), events that are all … Most metamorphic textures … Metamorphic rocks exhibit a variety of textures. This type of metamorphism occurs over large areas that were subjected to high degrees of deformation under differential stress. Other chapters survey the textures of rocks under dynamic and shock metamorphism. This book will be of great use to petrologists, physicists, and graduate and undergraduate petrology students. Regional metamorphism is primarily due to tectonic forces associated with the interaction between lithospheric plates. The original plagioclase phenocrysts are the light-colored blocks in the lower-left and upper-left of this … Regional Metamorphism Regional metamorphism occurs over large areas and generally does not show any relationship to igneous bodies. Most regional metamorphism is accompanied by deformation under non-hydrostatic or differential stress conditions. It is a high-grade metamorphic rock in which mineral grains recrystallized under intense heat and pressure. The final chapters describe the textures of regional and polymetamorphism. This is commonly associated with convergent plate boundaries and the formation of mountain ranges. Regional metamorphism. Regional Metamorphism A change in the texture, structure, or chemical composition of a rock due to changes in temperature and pressure over a large area, generally as a result of tectonic forces Foliation Regional metamorphism is a type of metamorphism where rock minerals and texture are changed by heat and pressure over a wide area or region. • Processes leading to texture formation • Textures of Contact Metamorphism • High Strain Metamorphic Textures • Regional Metamorphic Textures • Replacement Textures and Reaction Rims 2. The final chapters describe the textures of regional and polymetamorphism. This is a porphyritic basalt that was regionally metamorphosed to epidote amphibolite facies. This occurs in areas of active subduction … Because burial to 10 km to 20 km is required, the areas affected tend to be large. Other chapters survey the textures of rocks under dynamic and shock metamorphism. Rock in which mineral grains and segregated them into bands, a transformation which the! 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