Eocene–Oligocene extinction event in the context of "Extinction event"

The Last Glacial Period (LGP), also known as the last glacial cycle, occurred from the end of the Last Interglacial to the beginning of the Holocene, c. 115,000 – c. 11,700 years ago, and thus corresponds to most of the timespan of the Late Pleistocene. It thus formed the most recent period of what is colloquially known as the "Ice Age".

The LGP is part of a larger sequence of glacial and interglacial periods known as the Quaternary glaciation which started around 2,588,000 years ago and is ongoing. The glaciation and the current Quaternary Period both began with the formation of the Arctic ice cap. The Antarctic ice sheet began to form earlier, at about 34 Mya (million years ago), in the mid-Cenozoic (Eocene–Oligocene extinction event), and the term Late Cenozoic Ice Age is used to include this early phase with the current glaciation. The previous ice age within the Quaternary is the Penultimate Glacial Period, which ended about 128,000 years ago, was more severe than the Last Glacial Period in some areas such as Britain, but less severe in others.

The Late Cenozoic Ice Age, or Antarctic Glaciation, began 34 million years ago at the Eocene-Oligocene Boundary and is ongoing. It is Earth's current ice age or icehouse period. Its beginning is marked by the formation of the Antarctic ice sheets.

Six million years after the start of the Late Cenozoic Ice Age, the East Antarctic Ice Sheet had formed, and 14 million years ago it had reached its current extent.

The Eocene (IPA: /ˈiːəsiːn, ˈiːoʊ-/ EE-ə-seen, EE-oh-) is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name "Eocene" comes from Ancient Greek ἠώς (ēṓs), meaning "dawn", and καινός (kainós), meaning "new", and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.

The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope C in the atmosphere was exceptionally low in comparison with the more common isotope C. The average temperature of Earth at the beginning of the Eocene was about 27 degrees Celsius. The end is set at a major extinction event called the Grande Coupure (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain.

The Popigai impact structure is the eroded remnant of an impact crater in northern Siberia, Russia. It is tied with the Acraman impact structure as the fourth largest verified impact structure on Earth. A large bolide impact created the 100-kilometre-diameter (62 mi) crater approximately 35 million years ago during the late Eocene epoch (Priabonian stage). It might be linked to the Eocene–Oligocene extinction event.

The structure is 300 km (190 mi) east from the outpost of Khatanga and 880 km (550 mi) northeast of the city of Norilsk, NNE of the Anabar Plateau. It is designated by UNESCO as a Geopark, a site of special geological heritage. There is a small possibility that the Popigai impact crater may have formed simultaneously with the approximately 35-million-year-old Chesapeake Bay and Toms Canyon impact craters.