Search results
Results From The WOW.Com Content Network
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.
The intersection represents the likely P-T condition experienced by rock in its metamorphic history. Geothermobarometry is a quantitative measurement of the P-T conditions, which is widely used in analyzing the P-T conditions of metamorphic and intrusive igneous rocks .
Khondalite at Rushikonda, Visakhapatnam, India Khondalite is a foliated metamorphic rock.In India, it is also called Bezwada Gneiss and Kailasa Gneiss. [1] It was named after the Khond tribe [2] [1] of Odisha and Andhra Pradesh because well-formed examples of the rock were found in the inhabited hills of these regions of eastern India.
Impactite is rock created or modified by one or more impacts of a meteorite. [1] [2] Impactites are considered metamorphic rock, because their source materials were modified by the heat and pressure of the impact. [3] On Earth, impactites consist primarily of modified terrestrial material, sometimes with pieces of the original meteorite. [3]
Solidified lava flow in Hawaii Sedimentary layers in Badlands National Park, South Dakota Metamorphic rock, Nunavut, Canada. Geology (from Ancient Greek γῆ (gê) 'earth' and λoγία () 'study of, discourse') [1] [2] is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. [3]
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 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.
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.