High pressure can change an igneous rock into a _________ rock.
The smaller particles of rock or the remains of living things that make up sedimentary rocks are called _________.
Fossils usually occur in _________ rock.
Footprints and trails are examples of _________ fossils.
The law of superposition helps geologists determine the _________ age of a rock layer.
At the beginning of the Paleozoic Era, a great number of different types of organisms evolved in an event called the _________.
Rock layers are always _________ than the faults that cut across them.
On the geologic time scale, the Mesozoic Era is divided into the Triassic, Jurassic, and Cretaceous _________.
The era before the Mesozoic Era is the _________.
Generally, only the _________ parts of organisms become fossils.
Remains of prehistoric dead organisms
What is a fossil?