Rocks With Wavy Layers Are Foliated Metamorphic Rocks!
Do you see the little wavy layers in the pictures of foliated metamorphic rocks below?
All three of these rocks formed from a sedimentary rock called shale. With different amounts of metamorphism
, shale becomes different types of rocks!
(click for larger image)
|How Much Metamorphism?
|It looks like shale because it is dark in color and will break into thin
flat layers like shale often does. Unlike shale, slate makes a ringing sound
when you hit two pieces together.
|There are several different types of schist such as mica schist, garnet
schist, and chlorite schist depending on which minerals are found in the
rock. All schist contains mica.
|Gneiss (pronounced "nice")
|This striped rock often looks a bit like fudge swirl ice cream. The light
colored layers are usually quartz and feldspar and the dark layers (the
fudge!) are mostly mica.
Last modified August 11, 2003 by Lisa Gardiner.
You might also be interested in:
Mica minerals make some rocks sparkle! Look for them in your igneous and metamorphic rocks. Do they make your rocks sparkle? They break into flat plates because they have cleavage. ...more
This mineral is called quartz! Sometimes it looks white like milk but usually it looks clear like glass, sometimes with a little pink or gray tinge of color. You can find crystals of quartz in many different...more
This is a feldspar mineral! Look for it in igneous rocks where it looks like white or pink crystals. You might find it in other types of rocks as well. ...more
These are some of the initial findings of Mars Global Surveyor. There definitely is a magnetosphere near Mars. this finding suggests that scientists must rethink theories about the evolution of Mars. Surface...more
Spotting minerals is fun! There are many different types of minerals. Each has a different name and special traits. You can learn more about minerals by looking closely at them to understand their special...more
The mineral that is green is called olivine! Look for it in igneous and metamorphic rocks. In this picture, olivine is filling a hole in the igneous rock. ...more
There are at least 2000 minerals on Earth. That's a lot of minerals! But you don't need to know all of them to spot the minerals lurking in the rocks of your backyard. That is because only a small number...more