This crater is concentric with a larger and older formation lying along the southern rim.

The park is located on old geological formations of more than 2.7 billion years making it very much pre-Cambrian.

This is an old formation with a worn and rounded outer rim.

The authors therefore point out that in formations more than a few thousand years old, they may have missed the evidence for some quakes.

The Rock is said to be one of the oldest formations in the world.

A new housing development has been constructed on the old trackbed formation.

The Triassic rocks rest uncomfortably on all older formations within the county.

The 6th Division is the oldest formation of the army in Baghdad.

Almost all of these sandstone beds show the contortions shown by the older formation.

The quarry exposed a large volcanic formation between 200 and 250 million years old.