Conference proceeding
Timescale of events around the Cretaceous-Paleogene boundary; links between the Chicxulub impact, Deccan volcanism, and the Cretaceous-Paleogene boundary
American Geophysical Union Fall Meeting, Vol.2018
Dec 2018
Abstract
The Cretaceous-Paleogene boundary (KPB) mass extinction is one of the most significant biotic turnover events in Earth history. The KPB is important to study for several reasons, the most relevant being its implications on our understanding of the effects of abrupt climate change. While the temporal coincidence between the Chicxulub crater and the KPB has strongly implicated the impact as the main forcing mechanism for the mass extinction, the eruption of the Deccan Traps (DT) cannot be dismissed as a possible contributor. The timing of DT eruptions has been shown to span the KPB and, additionally, the onset of DT volcanism roughly coincides with Late Cretaceous records of environmental change. Both the Chicxulub impact and DT volcanism have similar environmental forcing mechanisms, albeit acting on different timescales. Until recently, insufficient geochronology has made it difficult to tease apart effects of either agent. To better understand the effects of both the Chicxulub impact and the DT in the KPB crises, we developed a high-precision chronologic framework that outlines the temporal sequence of biotic and climatic changes, and proposed perturbations, around the KPB using (super 40) Ar/ (super 39) Ar geochronology and paleomagnetism. From our results, salient findings include: 1) the decline in terrestrial faunas began between 400 ka and 150 ka pre-KPB, 2) terrestrial disaster faunas are constrained to the first approximately 25 ka of the Paleogene, and recovery occurred gradually over the next 850 ka, 3) the placement of the KPB in the DT sequence is coincident with changes in the magmatic plumbing system, strongly supporting a causal relationship between the DT state shift and the Chicxulub impact, 4) the DT erupted continuously from approximately 66.4 Ma to at least 65.4 Ma, with >75% of the volume post-KPB and, 5) the onset of volcanism is approximately coincident with the onset of pre-KPB warming, and the duration of post-KPB volcanism is equivalent to the duration of post-KPB ecological recovery. Overall, our new work highlights the close temporal relationship between the Chicxulub impact, Deccan volcanism, and the KPB. Our results suggest that the Chicxulub impact may have enhanced Deccan volcanism and ultimately imply that the KPB ecological crises were a result of the coupled system.
Metrics
6 Record Views
Details
- Title
- Timescale of events around the Cretaceous-Paleogene boundary; links between the Chicxulub impact, Deccan volcanism, and the Cretaceous-Paleogene boundary
- Creators
- Courtney J. Sprain - University of Florida Liverpool GBR United KingdomPaul R. RenneWilliam A. ClemensGregory P. WilsonStephanie M. SmithDonald L. LofgrenStephen SelfLoyc VanderkluysenKanchan PandeTushar MittalAnonymous
- Publication Details
- American Geophysical Union Fall Meeting, Vol.2018
- Conference
- American Geophysical Union Fall Meeting (2018)
- Publisher
- American Geophysical Union
- Resource Type
- Conference proceeding
- Language
- English
- Academic Unit
- Biodiversity, Earth, and Environmental Science (BEES)
- Identifiers
- 991021015347804721