In astronomy, geology, and paleontology, mya or "m.y.a." is an abbreviation for "million years ago". Like the related unit bya, mya is traditionally written in lower case.... to 2100 mya, during the Siderian
Siderian
The Siderian is the first geologic geologic period in the Paleoproterozoic era and lasted from 2500 annum to 2300 Ma . Instead of being based on stratigraphy, these dates are defined chronometrically.... and Rhyacian
Rhyacian
The Rhyacian is the second geologic geologic period in the Paleoproterozoic era and lasted from 2300 annum to 2050 Ma . Instead of being based on stratigraphy, these dates are defined chronometrically.... periods of the Paleoproterozoic
Paleoproterozoic
The Paleoproterozoic is the first of the three sub-divisions of the Proterozoic occurring between . This is when the continents first stabilized.... era. It was one of the most severe ice ages in geologic history and some geologists believe that it was very similar to the Snowball earth
Snowball Earth
Snowball Earth refers to hypotheses regarding paleoclimate global-scale glaciation, claiming that the Earth's surface was nearly or entirely frozen at some points in its past.... ice age that happened in the neoproterozoic
Neoproterozoic
The Neoproterozoic Era is the unit of geologic time scale from 1,000 to 542 +/- 0.3 million years ago. The terminal Era of the formal Proterozoic Eon , it is further subdivided into the Tonian, Cryogenian, and Ediacaran Periods.... era.
