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Geologic Time – Period prior to humans. 4.6 billion to 3 million years ago. (See "prehistoric periods" for more detail into this.) Primatomorphid Era – Period prior to the existence of Primatomorpha; Simian Era – Period prior to the existence of Simiiformes; Hominoid Era – Period prior to the existence of Hominoidea
The geologic time scale is a way of representing deep time based on events that have occurred throughout Earth's history, a time span of about 4.54 ± 0.05 Ga (4.54 billion years). [3] It chronologically organises strata, and subsequently time, by observing fundamental changes in stratigraphy that correspond to major geological or ...
Geologic time is the timescale used to calculate dates in the planet's geologic history from its origin (currently estimated to have been some 4,600 million years ago) to the present day. Radiometric dating measures the steady decay of radioactive elements in an object to determine its age. It is used to calculate dates for the older part of ...
1743 – Dr Christopher Packe produces a geological map of south-east England 1746 – Jean-Étienne Guettard presents the first mineralogical map of France to the French Academy of Sciences . 1760 – John Michell suggests earthquakes are caused by one layer of rocks rubbing against another
Geologic time shown in a diagram called a geological clock, showing the relative lengths of the eons of Earth's history and noting major events. The geological history of Earth follows the major geological events in Earth's past based on the geologic time scale, a system of chronological measurement based on the study of the planet's rock ...
As with other geological phenomena, orogenies are often subject to , type and associated paleogeography. In some (especially older) literature, the term orogeny refers to a long episode of basin formation and deposition of sediments over hundreds of millions of years, ending with deformation (sometimes including metamorphism) of these deposits ...
The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 251.9 Ma and 246.7 Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a unit in chronostratigraphy. The Early Triassic is the oldest epoch of the Mesozoic Era. It is ...
Palaeogeography of the Earth in Aptian. The Aptian is an age in the geologic timescale or a stage in the stratigraphic column.It is a subdivision of the Early or Lower Cretaceous Epoch or Series and encompasses the time from 121.4 ± 1.0 Ma to 113.0 ± 1.0 Ma (million years ago), approximately.