The Ordovician is a geologic period of the Paleozoic Era that follows the Cambrian and precedes the Silurian, spanning roughly 485 to 444 million years ago. It is characterized by extensive diversification of marine life, including brachiopods, trilobites, graptolites, and the first coral-stromatoporoid reef systems. Paleogeographically, continents were largely located in southern latitudes, with high sea levels producing widespread shallow epicontinental seas. The Ordovician ended with a major glaciation and associated mass extinction event, strongly linked to climatic cooling and sea-level fall, which significantly restructured marine ecosystems and marks the transition to the Silurian Period.
The Ordovician Period stands as a critical chapter in Earth's geological history, with carbon isotope records serving as both a key tool for stratigraphic correlation and a vital archive to unravel the coevolution of ancient ...
Earth Sciences
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The explosion of animal life in Earth's oceans half a billion years ago during and after the Cambrian Period is commonly attributed to a substantial and sustained rise of free oxygen (O2) in seawater. Some researchers even ...
Earth Sciences
Sep 4, 2025
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The "Big Five" mass extinctions of the Phanerozoic Eon have long attracted significant attention from the geoscience community and the public. Among them, the Late Ordovician Mass Extinction (LOME) is the earliest of the ...
Earth Sciences
Jun 5, 2025
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