The older materials are generally deeper, the newer materials are generally closer to the surface, and the vertical position of materials within the sequence provides a relative chronology that can be converted to an absolute chronology through radiocarbon dating.

But a cave is also an active environment.

The same wind that blows sediment into a cave can also rearrange what is already there.

The animals that use the cave — including the humans who visit it — can disturb the accumulated sediment.

Water infiltrating through the cave ceiling or floor can transport materials horizontally and vertically.

The very processes that make caves good preservation sites also introduce complexity into the stratigraphic record that must be carefully documented and understood.

The Paisley Caves record, read carefully and with appropriate attention to its complexities, preserves a detailed archive of environmental and human history in the northern Great Basin spanning more than 14,000 years.