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- Ordovician - Wikipedia
The Ordovician received international approval in 1960 (forty years after Lapworth's death), when it was adopted as an official period of the Paleozoic Era by the International Geological Congress
- Ordovician Period | Major Events, Extinction, Facts | Britannica
Ordovician Period, in geologic time, the second period of the Paleozoic Era It began 485 4 million years ago, following the Cambrian Period, and ended 443 8 million years ago, when the Silurian Period began
- The Ordovician Period
The Ordovician Period lasted almost 45 million years, beginning 488 3 million years ago and ending 443 7 million years ago * During this period, the area north of the tropics was almost entirely ocean, and most of the world's land was collected into the southern supercontinent Gondwana
- Ordovician Period—485. 4 to 443. 8 MYA - U. S. National Park Service
The Ordovician System rounded out the threefold division of early Paleozoic rocks (i e , Cambrian, Ordovician, and Silurian), which are all named for Welsh tribes
- Ordovician - New World Encyclopedia
The Ordovician, named after the Welsh tribe of the Ordovices, was defined by Charles Lapworth, in 1879, to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, who were placing the same rock beds in northern Wales into the Cambrian and Silurian periods, respectively
- Prehistoric Life During the Ordovician Period - ThoughtCo
The Ordovician is the second period of the Paleozoic Era (542-250 million years ago), preceded by the Cambrian and succeeded by the Silurian, Devonian, Carboniferous and Permian periods
- Ordovician Period Information and Facts - National Geographic
During the Ordovician period, part of the Paleozoic era, a rich variety of marine life flourished in the vast seas and the first primitive plants began to appear on land—before the second largest
- Ordovician Period | Natural History Museum
The Ordovician* lasted about 45 million years and saw the transition from very primitive to relatively modern life-forms in the seas
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