Making the base of the Darriwilian easily correlatable.

Subsequent surveys of other ocean ridges showed similar and correlatable anomalies in every case.

Strata from widespread locations containing the same fossil fauna and flora are correlatable in time.

The mushrooms appeared mostly from August to November, tended to grow in clumps, and the spatial distribution of clumps was random-the location of the clumps was not correlatable with appearances in previous years.

Second, regionally or globally correlatable chemostratigraphic signals can be found in rocks whose formation time is well-constrained by radionuclide dating of the strata themselves or by strata easily correlated with them, such as a volcanic suite that interrupts nearby strata.

Thus in the valuable Brockman Iron Formation of the Hamersley Basin, bands about an inch thick are said to be correlatable over an area of some 20000 square miles and even microscopic varves within those bands can be traced over 185 miles.

In volume two of Das Antlitz der Erde Suess set out his belief that across geologic time, the rise and fall of sea levels were mappable across the earth, that is, that the periods of ocean transgression and regression were correlatable from one continent to another.