The Rock Cycle. Woopee.

Question 2:
It is generally true that the more ancient rocks (i.e. Precambrian) are less widely found exposed at the Earth’s surface and that their geologic histories are more difficult to interpret. Consider why this should be so in the context of the Rock Cycle.
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The Rock Cycle is not just a process, but THE process rocks go through. They start off as igneous rocks, then into sediment, then change to sedimentary, then to metamorphic. It’s a large circle, hence the name, rock “cycle.”
The Precambrian rocks go through this process, just like any other rock. They don’t get special treatment because they are just so awesome. The lava from a Precambrian volcano will erupt, sending tons of noxious gas into the sky, while spewing miles upon miles of lava onto the earth’s floor. This lava will eventually cool, forming the igneous rocks we’ve all come to know and love. After time however, through weathering and erosion, it will become a dull, boring pile of sediment. This sediment, through many ways of deposition, burial, compaction, or cementation, will become a Sedimentary Rock. But this is short lived because here comes Mr. Heat and Doctor Metamorphism ready to spoil the party. They say “hey you, rock, we’re gonna pressure you to become a Metamorphic Rock.” Ted the Sedimentary Rock has no choice. He gives in to their demands and becomes a Metamorphic rock. Luckily for Ted, since he has magically found his way into the center of Earth (that’s where Metamorphic rocks are usually found), he becomes so hot and melts into magma. Then he is erupted through a volcano and everything begins again. He is given a second chance, but he’s learned time and time again that the same stuff will happen. Poor Ted the Sed.
As you can see, any rocks that existed during the Precambrian Era will be very rare because it has gone through the rock cycle and gone through many different stages and forms, hardly recognizable from it’s original shape and size. While it’s true that we could potentially be walking all over Precambrian rocks, we wouldn’t be able to recognize them as easily because they’ve been through the rock cycle numerous times.