Sounds like you want to write a paper about
Physical Geochemistry! (with an emphasis on rocks and stuff)
I LOVE geochemistry, even though I'm more into the analytical side of things now, but I digress...
There's SO much to cover, as Borek said, but it's probably manageable. For a term paper or something, it's an acceptable topic...if you were writing a journal article, it'd have to be WAY more specific.
SO much to cover...
Heat transfer --> Why Geysers are Hot, why certain rocks get hot faster, maybe even the properties of salt vs fresh water? How long does it take for lava to cool and form an igneous rock?
Thermodynamics --> Every rock and mineral has a crystal structure...and crystal structures are KEY to measuring bond energies, entropy, and properties and stuff...
Kinetics --> Rates of reaction in nature! Acid rain eroding limestone and other rocks...deposition and erosion...melting of ice formations (to form geological landmarks like drumlins, etc)
Maybe all those examples are too specific for a term paper, but maybe it got your mind churning.
Lucky for you there's a
peer-reviewed book about this stuff! It's called
Advances in Physical Geochemistry by Saxena and Bell. Go to
http://www.worldcatlibraries.org/wcpa/top3mset/adedfe4612c7d3b9.html for details...it's a multi-volume book I believe...even to get your hands on the table of contents would give your paper structure, breadth and a wide range of topics!
Let us know if you need anything else!