METAMORPHIC ROCKS Are rocks that have been altered
METAMORPHIC ROCKS Are rocks that have been altered or have undergone change. Metamorphic rocks begin as either igneous, sedimentary or another metamorphic rock…we call the beginning (1 st) rock the parent rock. The parent rock is under tons and tons of pressure, which causes heat to build up, causing the parent rock to SOFTEN or RECRYSTALLIZE and change or “morph” into a metamorphic rock
Parent Rock morphs into Metamorphic Rock Granite (Ign) Gneiss Sandstone (Sed) Quartzite Shale (Sed) Slate
Parent Rock morphs into Limestone (Sed) Metamorphic Rock Marble
METAMORPHIC ROCK SEDIMENTARY ROCK IGNEOUS ROCK Metamorphic rock (marked altered rock) formed when the sedimentary rock surrounding the magma was softened (NOT MELTED) by the heat from the magma. The melted rock becomes an igneous rock
Metamorphic Rocks are classified as either foliated or nonfoliated 1. FOLIATED • When the parent rock softens the mineral grains are flatten by heat and pressure • This causes the metamorphic rock to show a striped or banded look in some rocks • Examples of foliated metamorphic rocks are gneiss, schist and slate Granite foliates into Gneiss parent rock foliated metamorphic rock
Examples of foliated metamorphic rocks are Gneiss A beautiful specimen of foliation… gneiss Slate Schist
Which sample shows foliation? #1 Which sample is showing finegrained igneous rock? #2 Which sample is showing a sedimentary rock? #4
2. NON-FOLIATED • Mineral grains grow and rearrange, but do not form bands or stripes • Examples of nonfoliated metamorphic rocks include quartzite and marble Quartzite magnified quartzite no bands stripes
FOLIATED OR NON-FOLIATED 1. 2. FOLIATED NON-FOLIATED 4. 3. FOLIATED NON-FOLIATED
AMAZING EARTH SCIENCE FACTS 1. Metamorphic rocks are formed by _________ heat and pressure 2. Metamorphic rocks include: 1. _____ (banded) Foliated • Examples are slate, schist and gneiss 2. _______(no stripes) Non-Foliated • Examples include marble and quartzite Parent Rock Metamorphic Rock Limestone morphs into Sandstone morphs into Shale morphs into _________ marble _____ quartzite _______ and then into slate schist
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