Cretaceous
The Cretaceous period is part of the geologic system of classifying geologic formations. It is part of the Mesozoic era, and is divided into Early and Late epochs. The Cretaceous is preceded by Jurassic period and followed by the Paleogene period of the Cenozoic era. While there is no set date for the beginning of the period, the end of the period is associated with a worldwide layer of iridium-rich sediments which geologists have located. This layer is often called the KT Boundary, and has been hypothesized to be associated with a cataclysmic event - such as an asteroid or comet impacting the Earth - that wiped out all life on the planet.
The Cretaceous was named from the Latin word for chalky, and was first used in 1832.[1][2]
Under the dates assigned by uniformitarian geologists, it represents approximately the period of Earth's history from 145 million years ago to 65 million years ago.[3] The worldwide iridium layer provides the approximate date of the end of the period, as it has been dated using radioactive isotopes to around 65.5 million years old.
Flood geologists reject the uniformitarian assumptions behind the dates derived by secular geologists, so they reject these dates (see geologic system).
References
- ↑ Online Etymology Dictionary
- ↑ Jurassic Period (Department of Earth Science, University of California, Santa Barbara).
- ↑ Gradstein, F.M., and Ogg, J.G.,Geologic Time Scale 2004 – Why, How, and Where Next!