Understanding Metamorphic Rocks: Platforms, Mountain Belts, and Foliation, Quizzes of Geology

Download Understanding Metamorphic Rocks: Platforms, Mountain Belts, and Foliation and more Quizzes Geology in PDF only on Docsity! TERM 1 Platforms, Mountain Belts, shields DEFINITION 1 Metamorphic rocks broken into three categories: Continent is made out of three ypes Platforms: undeformed sedimentary rocks lying on top of older rocks Mountain Belts: deformed rocks Shields: old mountain belt rocks [all continents have it] TERM 2 Metamorphic rocks DEFINITION 2 Metamorphic rock is the result of the transformation of an existing rock type, the protolith, in a process called metamorphism, which means "change in form". Alteration of existing rocks by heat, pressure, reactive fluids, or some combination. Metamorphic rocks: The record of mountain building on Earth. Continents are built out of mountain belts. TERM 3 Metamorphic Changes DEFINITION 3 Textural: grains grow into place and interlock; changing the mineral orientation; most minerals have elongation; should you apply pressure, they will line up folia Mineral grains line up; mineral assemblage Foliation is an allgnment due to pressure; response to pressure; Foliated rocks have mineral grains in parallel alignment. TERM 4 foliation DEFINITION 4 Foliation is any penetrative planar fabric present in rocks. Foliation is a response to pressure. Compressive or shear. Shearing: deck of cards; applied forced; shearing deck of cards Anything not originally parallel will become parallele How does it develop? Mineral grain reorientation. Pressure solution or plastic deformation. Some minerals would dissolve after pressure Side not getting squeezed; materials precipicate TERM 5 Foliation vs. bedding DEFINITION 5 Not the same thing Apply pressure parallel to bedding plane, squeeze, produce rock cleavage cleavage planes dorm perpendicular to the direction of compression Slaty cleavage forms in response to differential stress