Ordovician Period
E90440
The Ordovician Period was a Paleozoic era interval marked by extensive marine biodiversity, the diversification of early vertebrates and invertebrates, and ending with one of Earth's major mass extinction events.
Aliases (4)
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
Paleozoic period
→
geological period → |
| characterizedBy |
Great Ordovician Biodiversification Event
→
abundant brachiopods → abundant bryozoans → abundant crinoids → abundant trilobites → diversification of early vertebrates → diversification of marine invertebrates → expansion of shallow epicontinental seas → extensive graptolite faunas → first coral reefs → first evidence of terrestrial fungi → first land plants → high marine biodiversity → widespread carbonate platforms → |
| climate |
cooling trend in Late Ordovician
→
generally warm greenhouse climate in early and middle Ordovician → |
| definedBy |
International Commission on Stratigraphy
→
|
| duration |
about 41.6 million years
→
|
| end |
approximately 443.8 million years ago
→
|
| endedWith |
Late Ordovician mass extinction
→
|
| follows |
Cambrian Period
→
|
| GSSPBaseDefinedBy |
first appearance of conodont Iapetognathus fluctivagus
→
|
| GSSPTopDefinedBy |
first appearance of graptolite Akidograptus ascensus
→
|
| majorContinent |
Baltica
→
Gondwana → Laurentia → Siberia → |
| massExtinctionCauses |
glaciation on Gondwana
→
global cooling → sea-level fall → |
| massExtinctionSeverity |
one of the largest mass extinctions in Earth history
→
|
| namedAfter |
Ordovices (ancient Welsh tribe)
→
|
| notableLifeForm |
conodonts
→
jawless vertebrates (agnathans) → nautiloid cephalopods → planktonic graptolites → rugose corals → tabulate corals → |
| paleogeography |
Gondwana located near the South Pole
→
Laurentia near the equator → |
| partOf |
Paleozoic Era
→
|
| precedes |
Silurian Period
→
|
| start |
approximately 485.4 million years ago
→
|
| stratotypeRegion |
Ordovician region of Wales
→
|
| subdividedInto |
Early Ordovician
→
Late Ordovician → Middle Ordovician → |
Referenced by (14)
| Subject (surface form when different) | Predicate |
|---|---|
|
Appalachian orogeny
→
Caledonian orogeny ("Ordovician period") → closure of Iapetus Ocean → |
startTime |
|
Paleozoic Era
→
Phanerozoic Eon → |
contains |
|
Agnatha
("Ordovician period")
→
|
diversifiedIn |
|
Embryophyta
("Ordovician period")
→
|
firstAppearance |
|
Amadeus Basin
("Ordovician")
→
|
geologicalPeriod |
|
International Chronostratigraphic Chart
→
|
includes |
|
Taconic Mountains
("Ordovician period")
→
|
orogenyAge |
|
Great Ordovician Biodiversification Event
→
|
partOf |
|
Cambrian Period
→
|
precedes |
|
Charles Lapworth
("Ordovician as a separate geological period between Cambrian and Silurian")
→
|
proposed |
|
Ordovician Period
("Early Ordovician")
→
|
subdividedInto |