Geologic History Vocabulary

Front

What does the principle of uniformitarianism state?

Back

Geological processes have always occurred at the same rate.

Front

What is absolute dating?

Back

A method of determining the age of an object in years.

Front

What does the principle of superposition state?

Back

In any sequence of undisturbed layers of sedimentary rock, the oldest layer is at the bottom and the layers become progressively younger toward the top.

Front

What is seafloor spreading?

Back

The process by which new oceanic lithosphere forms at mid-ocean ridges.

Front

What does a fossil ammonite represent?

Back

Remains of an extinct sea mammal.

Front

What is relative dating?

Back

A technique used to estimate the relative age of fossils.

Front

What is the significance of fossils in geology?

Back

Fossils provide evidence of past life and can help determine the age of rock layers.

Front

What is the rock cycle?

Back

The continuous process of rock formation, breakdown, and reformation.

Front

What is a geological time scale?

Back

A system of chronological dating that relates geological strata to time.

Front

What is the difference between igneous and sedimentary rocks?

Back

Igneous rocks form from cooled magma or lava, while sedimentary rocks form from the accumulation of sediment.