Metamorphism Processes/ Products Flashcards
A low temperature, brittle grain-fracturing process that involves grain size reduction through the mechanical grinding, rotation and crushing of rock.
Cataclasis
A fine-grained, non- foliated, clastic metamorphic rock produced by cataclastic processes.
Cataclasite
A ductile grain reduction
process that produces oriented grains of smaller diameter
Mylonitization
A product of mylonitization characterized by grain size reduction via macroscopic scale cataclisis, plastic stretching and thinning associated with ductile deformation.
Mylonite
Occurs in metamorphic rocks
where individual atoms or molecules can migrate in gaseous, liquid or solid phases from one location in a rock body to a new location.
Diffusion
Involves the dissolution of solid grains under high compressive stress conditions.
Pressolution
An insoluble seam that accumulates as soluble minerals dissolve.
Stylolite
Occurs when existing minerals are transformed under higher temperature and/or pressure conditions, without experiencing a significant change in chemical composition.
Recrystallization
The nucleation and growth of new minerals as pre-existing minerals become unstable due to temperature or pressure changes.
Neocrystallization
Newly formed minerals that are distinctly larger than the minerals in the surrounding matrix.
Porphyroblasts
The segregation of minerals in an initially homogenous rock due to different physical or chemical characteristics such as solubility, ductility, mineral growth, or crystallization temperature.
Differentiation
Partially melted rocks that form by quenching under high strain rates in shear zone fractures.
Pseudotachylites
A metamorphic halo in the contact zone that surrounds it, produced from the heat of the igneous intrusion, and can range from centimeters to hundreds of meters in diameter.
Aureole