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- Cretaceous - Wikipedia
It is the third and final period of the Mesozoic Era, as well as the longest At around 77 1 million years, it is the ninth and longest geological period of the entire Phanerozoic The name is derived from the Latin creta, ' chalk ', which is abundant in deposits from the latter half of the period
- Cretaceous Period | Definition, Climate, Dinosaurs, Map - Britannica
Cretaceous Period, in geologic time, the last of the three periods of the Mesozoic Era It began 145 million years ago and ended 66 million years ago and featured the extinction of the dinosaurs at the end of the period
- The Cretaceous Period: What was Earth like before dinosaurs went . . .
The Cretaceous Period lasted for nearly 80 million years Discover what the climate was like in this geological period, where the continents were and what animals and plants lived on them Find out how an asteroid ended the age of dinosaurs
- Cretaceous Period—145. 0 to 66. 0 MYA (U. S. National Park Service)
In 1882 a Belgian geologist, Omalius d’Halloy, proposed the term “Cretaceous” for strata encircling the Paris Basin in France The term derives from the Latin word for chalk (“creta”) and describes thick deposits of calcium carbonate (CaCO 3) ooze and chert (SiO 2)
- Cretaceous - New World Encyclopedia
The Cretaceous period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic period, from about 146 to 136 million years ago (Ma) to the beginning of the Paleocene epoch of the Paleogene period, or Tertiary sub-era (about 65 5 to 64 Ma)
- The Cretaceous Period
The Cretaceous is defined as the period between 145 5 and 65 5 million years ago,* the last period of the Mesozoic Era, following the Jurassic and ending with the extinction of the dinosaurs (except birds)
- Cretaceous period: Animals, plants and extinction event
The Cretaceous period lasted approximately 79 million years, and ended with a major extinction event about 66 million years ago
- Cretaceous Period | Natural History Museum
Ocean basin volumes diminished and the seas reached their highest levels during the Cretaceous Period, resulting in vast shallow continental seas Huge deposits of chalk left from the skeletal remains of marine organisms, give the period its name
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