Drew Holt

 a mountain mostly made of rock layers being squeezed together

huge tilted rocks separated by a fault

the breaking down of rocks by natural process

the picking up and removal of rocks

a mixture of rock, air, water, living things, and humus

a mixture of dead plants and animals

the layers of the soil from the surface to bedrock

water that seeps underground

the downhill movement of Earth material caused by gravity

the dropping off of sediment 

a huge sheet of  ice and snow that moves slowly 

a jumble of many sizes of sediment deposited by a glacier 

a deposit of many sizes of sediment by a glacier

a naturally occurring solid in Earth's crust

a rock that forms when molten rock cools and hardens

a rock that forms from pieces of other rock squeezed together

a rock that forms from another kind of rock that is changed by heat, pressure, or a chemical reaction

rocks continually changing in a never ending cycle

the idea that the youngest rock layer is at the top and the oldest is at the bottom

the age of a rock compared to another rock

a list of Earth's rock layers from oldest to youngest

any trace, imprint , or remains of a living creature in Earth's crust

the remains of a living thing that was widespread, but lived a short part in Earth's history

the time it takes for the radioactive element in a rock to decay

the age of rock in years 

one of the four stretches of time in Earth's history