Metamorphic rock Metamorphic rock Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means "change in form". The original rock (protolith) is subjected to heat (temperatures greater than 150 to 200 °C) and pressure ( or more), causing profound physical or chemical change. The protolith may be a sedimentary, igneous, or existing metamorphic rock. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by texture and by chemical and mineral assemblage (metamorphic facies). They may be formed simply by being deep beneath
Sort Sol Sort Sol Sort Sol is a pioneer rock band from Copenhagen, Denmark. The band was formed in 1977 as a punk rock outfit, originally under the name Sods (stylized as SODS). The name "Sort Sol" was taken in the early 1980s. It translates to English as "black sun" and is named after a nature phenomenon particular to Denmark, where huge bird flocks gather in the sky and appear to block out the sun. For reasons unknown, the Danish press often refers to their musical style as punk due to their origin, though nearly everything they have put out since 1980