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The '''Cretaceous''' [[period (geology)|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.

The '''Cretaceous''' [[period (geology)|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.<ref>[http://www.etymonline.com/index.php?term=cretaceous Online Etymology Dictionary]</ref><ref>[http://www.geol.ucsb.edu/Outreach/TimeScale/jurassic.html Jurassic Period] (Department of Earth Science, University of California, Santa Barbara).</ref>

The Cretaceous was named from the [[Latin]] word for ''chalky'', and was first used in 1832.<ref>[http://www.etymonline.com/index.php?term=cretaceous Online Etymology Dictionary]</ref><ref>[http://www.geol.ucsb.edu/Outreach/TimeScale/jurassic.html Jurassic Period] (Department of Earth Science, University of California, Santa Barbara).</ref>

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.<ref>Gradstein, F.M., and Ogg, J.G.,[http://www.stratigraphy.org/scale04.pdf Geologic Time Scale 2004 – Why, How, and Where Next!]</ref>   

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.<ref>Gradstein, F.M., and Ogg, J.G.,[http://www.stratigraphy.org/scale04.pdf Geologic Time Scale 2004 – Why, How, and Where Next!]</ref>  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 Geology|Flood geologists]] reject the [[uniformitarian]] assumptions behind the dates derived by secular geologists, so they reject these dates (see [[geologic system]]).

[[Flood Geology|Flood geologists]] reject the [[uniformitarian]] assumptions behind the dates derived by secular geologists, so they reject these dates (see [[geologic system]]).