What is a metamorphic rock? How is it formed? Metamorphic Rock Chapter 6, Section 3 Scripps Classroom Connection

How to make a metamorphic rock Take any kind of rock  Cook at ______ to ~______°C  Above ~650°C rocks start to melt  Bury to 2-45 km (pressure of 1-15 kb)  Apply water — Remember!?! Water ________ the melting point of rocks Scripps Classroom Connection

Factors Controlling Metamorphism Primary:  _______________ Secondary:  Presence of __________________ fluids Scripps Classroom Connection

Pressure Scripps Classroom Connection ____________ Pressure: same pressure from all directions. ____________ Pressure: unequal pressure from different directions

Directed Pressure Scripps Classroom Connection

● __________: minerals are arranged in layers or bands ● __________: not layered; minerals grow in the same size and shape Metamorphic Rock Textures Scripps Classroom Connection Animation

Foliation becomes more distinct with increased temperature and pressure Crystals grow ______________ Foliation becomes more _______________ Order schist, slate, and gneiss with increasing foliation and explain why. Scripps Classroom Connection

Effects of Hydrothermal Fluids Heating rock underground can produce _________ and _______. Fluids ___________ and ___________ ions throughout large regions of rock Rocks change ___________________ into different mineralogy and texture. Scripps Classroom Connection

Three Types of Metamorphism Contact Regional Hydrothermal Scripps Classroom Connection

Relation of Metamorphic Rocks to Plate Tectonics

● Metamorphism involves a change in rock ● Metamorphism occurs under three conditions ● Metamorphic rocks are classified into two main groups ● There are two overall categories of metamorphism according to how they are formed, and the area of rock affected Overview Scripps Classroom Connection