What is the shortest time interval on a geologic time scale?

Answer 1

The shortest era in geological time is the Cenozoic Era, the current era. It started 65.5 million years ago with the K-T extinction event.

List from longest to shortest.

Paleoproterzoic (2,500 - 1,600 ma) - 900 million years

Mesoproterzoic (1,600 - 1,000 ma) - 600 million years

Neoproterzoic (1,000 - 542 ma) - 458 million years

Paleoarchean (3,600 - 3,200 ma) - 400 million years

Meseoarchean (3,200 - 2,800 ma) - 400 million years

Neoarcheasn (2,800 - 2,500 ma) - 300 million years

Paleozoic (542 - 251 ma) - 291 million years

Eoarchean (3,800 - 3,600 ma) - 200 million years

Mesozoic (251 - 65.5 ma) 185 million years

Cenozoic (65.5 ma - Now) 65.5 million years

Answer 2

The study of the Earth from the beginning of time to the present has been the task of geologists who attempt to unravel the events that have shaped our planet as it is today. The Earth carries the history of geological events in its rock layers. It follows that the oldest layers are at the bottom and the youngest are at the top. With this understanding geologists are able to determine the ages of rock relative to one another. By assembling all these layers together, scientists have worked out what is known as the stratigraphic column or record of the various ages of rock. This record spans the 4.6 billion year record of Earth's history.

In order to simplify the huge amount of geological information, geologists have broken Earth's history down into sections which are called geological eras, periods, and epochs. Fossils records have shown that life existed for about 3,800 million years, but complex life emerged only about 600 million years. Over time, life forms change. Their fossil record allows geologists to date and compare rocks across geological time. For example, dinosaur fossils are only found during the Mesozoic era some 245 to 65 million years ago.

Answer 3

it is an epoch. 4 mo answers link http://en.wikipedia.org/wiki/Geologic_time_scale

Answer 4

Cenozoic