Cretaceous–Paleogene boundary

E6899

chronostratigraphic boundary geological boundary mass extinction boundary

The Cretaceous–Paleogene boundary marks the geological transition 66 million years ago associated with a mass extinction event that wiped out non-avian dinosaurs and many other species, likely triggered by a large asteroid impact.

Jump to: Surface forms Statements Referenced by

Observed surface forms (7)

Surface form	Occurrences
Cretaceous–Paleogene extinction event	8
Chicxulub impact event	2
Cretaceous–Paleogene boundary layer	1
Cretaceous–Paleogene mass extinction	1
Cretaceous–Tertiary boundary	1
K–Pg boundary	1
K–T boundary	1

Statements (48)

Predicate	Object
instanceOf	chronostratigraphic boundary ⓘ geological boundary ⓘ mass extinction boundary ⓘ
age	about 66 million years ago ⓘ
alsoKnownAs	Cretaceous–Paleogene boundary ⓘ surface form: K–Pg boundary Cretaceous–Paleogene boundary ⓘ surface form: K–T boundary
associatedWith	Cretaceous–Paleogene boundary self-linksurface differs ⓘ surface form: Cretaceous–Paleogene extinction event extinction of ammonites ⓘ extinction of many marine reptiles ⓘ extinction of many plankton species ⓘ extinction of many terrestrial plant species ⓘ mass extinction of non-avian dinosaurs ⓘ
cause	large asteroid impact ⓘ
characterizedBy	abrupt faunal turnover ⓘ abrupt floral turnover ⓘ negative carbon isotope excursion in some sections ⓘ
correlatesWith	Chicxulub impact crater ⓘ
definedBy	first appearance of Paleogene fossils above boundary ⓘ last appearance of many Cretaceous taxa below boundary ⓘ
evidence	global iridium-rich clay layer ⓘ microtektites ⓘ shocked quartz ⓘ spherules from impact ejecta ⓘ
formerlyKnownAs	Cretaceous–Paleogene boundary self-linksurface differs ⓘ surface form: Cretaceous–Tertiary boundary
globalExtent	worldwide ⓘ
impactOn	evolution of mammals ⓘ radiation of birds ⓘ restructuring of marine ecosystems ⓘ restructuring of terrestrial ecosystems ⓘ
linkedTo	short-term global cooling followed by warming ⓘ sudden collapse of primary productivity in surface oceans ⓘ wildfires on a global or near-global scale ⓘ
locatedInTimeScale	International Chronostratigraphic Chart ⓘ
marksBeginningOf	Cenozoic ⓘ surface form: Cenozoic Era
marksEndOf	Mesozoic Era ⓘ
marksTransitionBetween	Cretaceous ⓘ surface form: Cretaceous Period Paleogene ⓘ surface form: Paleogene Period
ratifiedBy	International Commission on Stratigraphy ⓘ
recognizedBy	distinct boundary clay layer in many sections ⓘ
relatedTo	Deccan Traps volcanism ⓘ
scientificDebate	relative roles of impact and volcanism in extinction ⓘ
separates	Upper Cretaceous strata from lower Paleogene strata ⓘ
stratigraphicRank	system/period boundary ⓘ
timeEquivalentOf	Cretaceous–Paleogene boundary self-linksurface differs ⓘ surface form: Cretaceous–Paleogene extinction event
usedIn	biostratigraphy ⓘ chemostratigraphy ⓘ geochronology ⓘ magnetostratigraphy ⓘ

Referenced by (17)

Full triples — surface form annotated when it differs from this entity's canonical label.

Cretaceous–Paleogene boundary → alsoKnownAs → Cretaceous–Paleogene boundary ⓘ

this entity surface form: K–Pg boundary

Cretaceous–Paleogene boundary → alsoKnownAs → Cretaceous–Paleogene boundary ⓘ

this entity surface form: K–T boundary

Cretaceous → associatedWith → Cretaceous–Paleogene boundary ⓘ

this entity surface form: Chicxulub impact event

Cretaceous–Paleogene boundary → associatedWith → Cretaceous–Paleogene boundary self-linksurface differs ⓘ