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Marble is a metamorphic rock consisting of carbonate minerals (most commonly calcite (CaCO 3) or dolomite (CaMg(CO 3) 2) that have recrystallized under the influence of heat and pressure. [1] It has a crystalline texture, and is typically not foliated ( layered ), although there are exceptions.
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock ( protolith ) is subjected to temperatures greater than 150 to 200 °C (300 to 400 °F) and, often, elevated pressure of 100 megapascals (1,000 bar ) or more, causing profound physical or chemical changes.
Hornfels – Group of metamorphic rocks Calcflinta – A type of hornfels found in the Scottish Highlands; Litchfieldite – Nepheline syenite gneiss; Marble – Type of metamorphic rock – a metamorphosed limestone; Migmatite – Mixture of metamorphic rock and igneous rock; Mylonite – Metamorphic rock – A metamorphic rock formed by shearing
For instance, the small calcite crystals in the sedimentary rocks limestone and chalk change into larger crystals in the metamorphic rock marble. [13] In metamorphosed sandstone , recrystallization of the original quartz sand grains results in very compact quartzite , also known as metaquartzite, in which the often larger quartz crystals are ...
Marble is a metamorphic rock derived from limestone, composed mostly of calcite (a crystalline form of calcium carbonate, CaCO 3).The original source of the parent limestone is the seabed deposition of calcium carbonate in the form of microscopic animal skeletons or similar materials.
In geology, solid-state recrystallization is a metamorphic process that occurs under high temperatures and pressures where atoms of minerals are reorganized by diffusion and/or dislocation glide. During this process, the physical structure of the minerals is altered while the composition remains unchanged.
Metamorphic banded gneiss. Metamorphic rocks are formed by subjecting any rock type—sedimentary rock, igneous rock or another older metamorphic rock—to different temperature and pressure conditions than those in which the original rock was formed.
Metamorphic rocks once existed as igneous or sedimentary rocks, but have been subjected to varying degrees of pressure and heat within the Earth's crust. The processes involved will change the composition and fabric of the rock and their original nature is often hard to distinguish. Metamorphic rocks are typically found in areas of mountain ...