What are the 4 periods of time used on the geologic time scale?
The Precambrian, Paleozoic, Mesozoic, and Cenozoic Eras The Geologic Time Scale is the history of the Earth broken down into four spans of time marked by various events, such as the emergence of certain species, their evolution, and their extinction, that help distinguish one era from another.
What are the 4 geological eras in order?
The four main ERAS are, from oldest to youngest: PreCambrian, Palaeozoic, Mesozoic and Cenozoic.
What are the 6 eras on the geologic time scale?
This scale is most detailed for the time in which life was abundant, as shown by fossils.
- Geological Timescale. The oldest fossils are between 3 billion and 3.5 billion years old.
- Phanerozoic Eon.
- Paleozoic Era.
- Mesozoic and Cenozoic Eras.
What are the geological eras?
There are three Geologic Eras currently identified. The Paleozoic Era, the Mesozoic Era, and the Cenozoic Era. See illustration at right. Each of the names of the Eras reflects the relative stage in the development of life. Paleozoic means old life, Mesozoic means middle life, and Cenozoic means new life.
What is the longest era of geologic time?
Precambrian
The longest geologic era was the Precambrian. It began with the formation of the earth about 4.53 billion years ago, and ended about 542 million years…
What do the eras of the geological time scale represent?
The Geologic Time Scale is the history of the Earth broken down into four spans of time marked by various events, such as the emergence of certain species, their evolution , and their extinction , that help distinguish one era from another.
What are the eras and periods of the geologic time scale?
Eons are the largest spans of time in the geologic time scale. Eons are divided into smaller units called eras. Eras are subdivided into periods. Periods are subdivided into even smaller time spans called epochs.
How many eras of geologic time make up the geologic time scale?
Eras of the Geologic Time Scale. The geologic time scale features four periods, the first one is the Precambrian era, followed by the Paleozoic era, Mesozoic era, and the Cenozoic era.
What do eras divide into in geological times?
Nowadays, and speaking very generally, geological time is divided first into four great chunks known as eras: Precambrian, Paleozoic (from the Greek meaning old life), Mesozoic (middle life), and Cenozoic (recent life).