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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.
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
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.
Metamorphic rocks are formed when existing rocks are subjected to such high pressures and temperatures that they are transformed without significant melting. Humanity has made use of rocks since the earliest humans. This early period, called the Stone Age, saw the development of many stone tools.
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.
The metamorphic facies is not usually considered when classifying metamorphic rock based on protolith, mineral mode, or texture. However, a few metamorphic facies produce rock of such distinctive character that the facies name is used for the rock when more precise classification is not possible. The chief examples are amphibolite and eclogite.
Granofels is a term referring to medium- to coarse-grained metamorphic rocks which have a granoblastic texture (having poorly formed, equi-granular crystal grains visible to the naked eye) and lack distinct foliation or lineation. [1] The granofels term encompasses rocks which are known under more specific names, such as marble or hornfels. [2]
In geology, metasedimentary rock is a type of metamorphic rock. Such a rock was first formed through the deposition and solidification of sediment. Then, the rock was buried underneath subsequent rock and was subjected to high pressures and temperatures, causing the rock to recrystallize. The overall composition of a metasedimentary rock can be ...