Search results
Results from the WOW.Com Content Network
The Ordovician–Silurian extinction events may have been caused by an ice age that occurred at the end of the Ordovician Period, due to the expansion of the first terrestrial plants, [54] as the end of the Late Ordovician was one of the coldest times in the last 600 million years of Earth's history.
The Late Ordovician mass extinction (LOME), sometimes known as the end-Ordovician mass extinction or the Ordovician-Silurian extinction, is the first of the "big five" major mass extinction events in Earth's history, occurring roughly 445 million years ago (Ma). [1]
The Great Ordovician Biodiversification Event (GOBE), was an evolutionary radiation of animal life throughout [1] the Ordovician period, 40 million years after the Cambrian explosion, [2] whereby the distinctive Cambrian fauna fizzled out to be replaced with a Paleozoic fauna rich in suspension feeder and pelagic animals.
The Cambrian–Ordovician extinction event, also known as the Cambrian-Ordovician boundary event, [1] was an extinction event that occurred approximately 485 million years ago in the Paleozoic era of the early Phanerozoic eon. [2]
The Late Ordovician Glaciation coincided with the second largest of the five major extinction events, known as the Late Ordovician mass extinction. This period is the only known glaciation to occur alongside of a mass extinction event. The extinction event consisted of two discrete pulses.
The Late Ordovician is the third and final epoch of the Ordovician period. [5] The rocks associated with this epoch are referred to as the Upper Ordovician series.. At this time, Western and Central Europe and North America collided to form Laurentia, while glaciers built up in Gondwana, which was positioned over the South Pole.
The Hirnantian is the final internationally recognized stage of the Ordovician Period of the Paleozoic Era.It was of short duration, lasting about 1.4 million years, from 445.2 to 443.8 Ma (million years ago). [8]
The Early Ordovician is the first epoch of the Ordovician period, corresponding to the Lower Ordovician series of the Ordovician system. It began after the Age 10 of the Furongian epoch of the Cambrian and lasted from 485.4 ± 1.9 to 470 ± 1.4 million years ago, until the Dapingian age of the Middle Ordovician .