1. Metamorphic Rocks: Windows into the Earth’s Interior Metamorphic rocks form by the alteration of pre-existing rocks in the solid state by heat, pressure, and chemically active fluids. There can be changes in both texture and mineralogy.

2. Agents of Metamorphism:

3. Scope of Metamorphism a) Contact b) Regional

4. Types of Metamorphic Rocks 1) Foliated – Directed pressure causes the mineral grains to align in planar layers, perpendicular to the direction of stress

5. Foliated Metamorphic Rocks Shale Slate Phyllite Schist Gneiss Increasing Metamorphism

6. Non-foliatedFoliated Minerals in Thin Section

7. SLATE SCHIST GNEISS Increasing Metamorphism

9. Non-Foliated Metamorphic Rocks Changes in minerology and texture without any planar alignment of minerals Statue carved from Marble, a metamorphosed limestone

10. Rock Name Parent Rock Mineralogy 1) QuartziteQuartz Sandstone Quartz 2) Marble Limestone Calcite 3) HornfelsBasalt Plagioclase Micas, Clays Ferromagnesians 4) GreenstoneBasaltPlagioclase Ferromagnesians NON-FOLIATED METAMORPHIC ROCKS

11. Quartzite Metaconglomerate Marble

14. Greenschist Facies Blueschist Facies

17. Garnets in a Gneiss