Marble Metamorphic Rock Grade

The specimen shown above is about two inches five centimeters across.

Marble metamorphic rock grade.

Marble is a non foliated metamorphic rock that is produced from the metamorphism of limestone or dolostone. As already noted slate is formed from the low grade metamorphism of shale and has microscopic clay and mica crystals that have grown perpendicular to the stress. The various types of foliated metamorphic rocks listed in order of the grade or intensity of metamorphism and the type of foliation are slate phyllite schist and gneiss figure 7 8. What is the metamorphic grade of marble.

It is composed primarily of the mineral calcite caco 3 and usually contains other minerals such as clay minerals micas quartz pyrite iron oxides and graphite. Variable grade regional or contact metamorphism along a convergent. Metamorphic rocks arise from the transformation of existing rock types in a process called metamorphism which means change in form. But grain size is also dependent on the grain size of the protolith.

The original rock is subjected to heat temperatures greater than 150 to 200 c and pressure 100 megapascals 1 000 bar or more causing profound physical or chemical change the protolith may be a sedimentary igneous or existing metamorphic rock. It is composed primarily of calcium carbonate. Volatiles are those chemical substances including water and carbon dioxide that easily turn into gas or fluid and are mobile enough to move in and out of solid rock. Metamorphic rocks form from pre existing rocks parent rocks due to changes in either temperature pressure or volatiles within the earth often by a combination of all three.

Low grade metamorphic rocks tend to be fine grained the newly formed metamorphic mineral grains that is. Metamorphic grade refers to the degree of heat and pressure needed to create a particular metamorphic rock out if its parent rock. Marble is a metamorphic rock that forms when limestone is subjected to the heat and pressure of metamorphism.