We used more old tunes like "Shenandoah," "Boll Weevil," and even
Sousa's "Washington Post March" to help you learn foundational geologic
information. To help you better understand the earth's surface and how
its concepts fit together, we organized the eighteen songs and chapters
into three groupings:
Authors: Dorry and Doug EldonIgneous Rock
to the tune of "Anchors Away"
Magma cools into rock, igneous rock
It's what's in both the other - sedimentary, metamorphic
Classification is by chemicals,
And texture from the crystals, large, or small or none at all
Igneous rock can be one of two kinds
Intrusive starts as magma and cools slowly underneath the
Ground - like in granite, large crystals explain
Why this abundant rock has coarser texture, it's the coarser grain
Igneous can also be extrusive rock
When magma becomes lava at the surface from volcanoes
Where it is quickly cooled, crystals are small
Finer grain the finer texture - the most common is basalt
Magma can turn to glass when it cools fast
No crystals in the dark obsidian, pumice bubbles within
So for texture there are these three kinds
With crystals large, or crystals small, or with crystals not at all.