Ordovician period


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Related to Ordovician period: Permian period, Devonian period, Silurian period

Ordovician period

The second period in the Paleozoic era: 505 to 438 million years ago.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.Ordovician period - from 500 million to 425 million years agoOrdovician period - from 500 million to 425 million years ago; conodonts and ostracods and algae and seaweeds
Paleozoic, Paleozoic era - from 544 million to about 230 million years ago
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
While oxygen was just 14 percent of the air in the middle of the Ordovician period, in a space of about 10 million years it jumped dramatically; it constituted almost a quarter of the atmosphere in the late part of that period.
The Great Stone, Church A BLUE plaque in old Northfield village says: "This glacial erratic boulder was formed in an explosive volcanic eruption during the Ordovician period, 450 to 460 million years ago.
THE GREAT STONE, CHURCH ROAD, NORTHFIELD A blue plaque in old Northfield village says: "This glacial erratic boulder was formed in an explosive volcanic eruption during the Ordovician period, 450 to 460 million years ago.
This dataset place the Upper Quartzite unit in the Ordovician period.
Most of the limestone along our shoreline is from the Ordovician Period Trenton or Black River formations.
The Appalachian basin contains two layers of buried energy--Utica shale from the middle Ordovician period and Marcellus shale from Devonian yield gas from Pennsylvanian and surrounding area wells.
Criptolithus & Eumorphocystis, Ordovician Period, 440-500mya
The earliest was during the late Ordovician period, 450 million years ago, when glaciation wreaked havoc.
Ormo and his colleagues, who studied two craters called Lockne and Malingen, which lie about 16km apart in northern Sweden results, found that the Malingen was of same age as Lockne, about 458 million years old, confirming that the area was rocked by a double asteroid strike during the Ordovician Period.

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