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The mountains of northwest Ireland were formed during the collision, as was the granite that is found in locations in Donegal and Wicklow. The Irish landmass was now above sea level and lying near the equator, and fossil traces of land-based life forms survive from this period.
Smith and others concluded that the Late Cretaceous drop in sea levels constituted the most severe marine regression of the entire Mesozoic Era. [102] D'Hondt and others argued that an asteroid impact at the end of the Cretaceous would not have produced enough acid for acid rain to be a significant factor contributing to the mass extinction. [56]
The Mesozoic Era [3] is the era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Periods.It is characterized by the dominance of gymnosperms such as cycads, ginkgoaceae and araucarian conifers, and of archosaurian reptiles such as the dinosaurs; a hot greenhouse climate; and the tectonic break-up of Pangaea.
Homininaeid Era – Period prior to the existence of Homininae Homininid Era – Period prior to the existence of Hominini Prehistory – Period between the appearance of Homo ("humans"; first stone tools c. three million years ago) and the invention of writing systems (for the Ancient Near East : c. five thousand years ago).
In Europe, most of the Lower Triassic is composed of Buntsandstein, a lithostratigraphic unit of continental red beds. [ citation needed ] The Early Triassic and partly also the Middle Triassic span the interval of biotic recovery from the Permian-Triassic extinction event , the most severe mass extinction event in Earth's history.
The event marks the end of the Mesozoic Era and the beginning of the Cenozoic Era. [12] "Tertiary" being no longer recognized as a formal time or rock unit by the International Commission on Stratigraphy, the K-T event is now called the Cretaceous—Paleogene (or K-Pg) extinction event by many researchers.
Template: Mesozoic graphical timeline. ... Print/export Download as PDF; ... An approximate timescale of key Mesozoic events.
The Triassic is the first and shortest period of the Mesozoic Era and the seventh period of the Phanerozoic Eon. Both the start and end of the period are marked by major extinction events. [10] The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic.