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The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after creta, the Latin word for the white limestone known as chalk.
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 Cretaceous is divided into Early and Late Cretaceous epochs, or Lower and Upper Cretaceous series. In older literature, the Cretaceous is sometimes divided into three series: Neocomian (lower/early), Gallic (middle) and Senonian (upper/late). A subdivision into 12 stages, all originating from European stratigraphy, is now used worldwide. In ...
The geologic time scale, proportionally represented as a log-spiral with some major events in Earth's history. A megaannus (Ma) represents one million (10 6) years.. The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth.
Late heavy bombardment of the Moon (and probably of the Earth as well) by bolides and asteroids, produced possibly by the planetary migration of Neptune into the Kuiper belt as a result of orbital resonances between Jupiter and Saturn. [5] "Remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia.
The Maastrichtian (/ m ɑː ˈ s t r ɪ k t i ə n / mahss-TRIK-tee-ən) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from .
Despite the western upheaval, the eastern US had achieved geological stability by the Late Cretaceous. [72] The weather was uniformly warm and rainy throughout the year. [85] Flowering plants were now common and fossil of broadleaf trees and shrubs were preserved in Late Cretaceous rocks. [85] The Cretaceous ended with another mass extinction.
The Late Cretaceous decapod crustacean assemblage of James Ross Island appears to have been mainly pioneer species and the ancestors of modern fauna, such as the first Antarctic crabs and the first appearance of the lobsters of the genera Linuparus, Metanephrops, and Munidopsis which still inhabit Antarctica today.