Earth Science 11
Name _________________
Metamorphic Rock
Read pages 63 – 66 in the text and fill in the blanks.
What Metamorphic Rocks Are
 Metamorphic (meta, change; morph, form) rocks are formed from ________________ by the action of ______,
_________, and ___________, especially water.
Dynamic Metamorphism
 Most of the metamorphic rock of Earth’s crust is formed by _____________________, which occurs during
mountain-building movements.
 Horizontal _______ of sedimentary rock deep down in the crust are subjected to both high _______________
and high ____________
 Heat from ________ of the moving rock layers is added to the heat already in the rocks.
 Pressure on the rocks comes from both the great _________ of the overlying rocks and the _____________
pressure of the moving rock _________.
 Hot _________, __________, and other liquids and gases in the deep rocks join with heat and pressure to
produce striking changes in the rocks.
 Pressure squeezes their _________ closer together, making them more _________ and less porous.
 Heat and chemicals may rearrange their ions or form new ones, making the rock more crystalline or even
changing their minerals.
 Examples: Sandstone -> ____________, Limestone -> _________
The Metamorphism of Shale
 When shale undergoes dynamic metamorphism, even more changes occur. Not only does the rock become
denser and more crystalline, but new minerals like mica and hornblende are formed.
 Tremendous pressures on the rock ________ the ________ of mica or the needles of hornblende into parallel
layers along which the new rock _______ easily. This new feature in the rock is called ___________.
 The first rock formed from shale during dynamic metamorphic is _______. In slate, the foliation layers are
microscopically ______. If metamorphism goes further, a shiny rock called __________ is formed.
 More intense metamorphism produces a flaky rock called _________, in which the foliation layers can easily be
seen. Schists can be formed from many different rocks, such as shales, impure sandstones, and basalt.
 _________ is another metamorphic rock formed from a variety of rocks. Gneiss has the ___________ foliation of
all the metamorphic rocks. Its minerals are arranged in cardboard-thin parallel brands in which _______ colored
minerals such as quartz and feldspar alternate with ________ minerals such as hornblende or biotite.
Thermal Metamorphism
 This process occurs when hot magma _________ its way into overlying _______.
 The heat of the magma _______ the surrounding rocks, so the process is also called __________ metamorphism.
 Hot liquids and gases from the magma also enter the __________ rock and ______ with its minerals. But these
effects rarely reach more than about a hundred meters into the intruded rock; so less rock is affected than in
dynamic metamorphism.
 Changes in the rock are usually _______ dramatic, and foliation is _________ produced.