geological time


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geological time

the period beginning with the formation of the earth and ending in the present day. It is often tabulated beginning with the Cambrian period, since the majority of fossil forms date from then. Precambrian time began with the formation of the earth about 4,600 million years ago. Dating of rocks is usually carried out by the measurement of radioactive decay. The older the rock the less radioactive it is. Organic remains are dated by CARBON DATING. See Appendix A.
References in periodicals archive ?
For that, we have to work on other types of marine organisms so that we clearly understand what took place in the sediment over geological time.
Critique: A work of solid scholarship that is exceptionally well written, organized and presented, "The Abyss of Time: A Study in Geological Time and Earth History" will prove to be an extraordinary and enduringly popular addition to both community and academic library science collections.
Bateman used examples of rock strata and minerals to illustrate the steady progress of geological time, and opposite them a series of fossils to chart the birth of fish, birds and mammals.
The Making Of Europe: A Geological History" relates how Europe has been assembled through geological time by the accretion of various distinct geological components, some of which have travelled a considerable distance across the globe to reach their present positions.
Because other researchers had used microfossils to pinpoint when in geological time each layer of the core had been deposited, Thomson and his colleagues knew when each of those 1,400 samples had been washed from Antarctica's surface into the sea.
Just as there is an ascending hierarchy of days, weeks, months and years in present time, there is a hierarchy of epochs, periods, eras and aeons in geological time.
ISLAMABAD -- A new modelling done by researchers has suggested that pivoting planets that lean one way and then change orientation within a short geological time period might be surprisingly habitable.
This time we started thinking about geological time spans and then looked at how materials are transformed from one state to another.
Beginning with an overview of Earth's geological history, geological time in general and a short introduction to mineralogy and general geology and plate tectonics and a short chapter about famous Tennessee geologists of the past, it delivers, as promised on the cover, a story of over a billion years of geological history of this surprisingly complex and geologically active part of the USA.
Ammonites are excellent index fossils, meaning it is often possible to link the rock layer in which a particular species is found to specific geological time periods.
Nicoll explained, adds greater insight to the process, and allows for detailed examination of magmatic and tectonic events across a region throughout geological time.
3 million years old according geological time period of Miocene.