CaltechAUTHORS
  A Caltech Library Service

Deposition and age of Chicxulub impact spherules on Gorgonilla Island, Colombia

Mateo, Paula and Keller, Gerta and Adatte, Thierry and Bitchong, André M. and Spangenberg, Jorge E. and Vennemann, Torsten and Hollis, Christopher J. (2019) Deposition and age of Chicxulub impact spherules on Gorgonilla Island, Colombia. Geological Society of America Bulletin . ISSN 0016-7606. (In Press) https://resolver.caltech.edu/CaltechAUTHORS:20190621-153144344

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20190621-153144344

Abstract

The end-Cretaceous mass extinction (66 Ma) has long been associated with the Chicxulub impact on the Yucatan Peninsula. However, consensus on the age of this impact has remained controversial because of differing interpretations on the stratigraphic position of Chicxulub impact spherules relative to the mass extinction horizon. One side argues that the impact occurred precisely at the Cretaceous-Paleogene boundary, thus coinciding with the mass extinction; the other side argues that the impact predated the Cretaceous-Paleogene boundary, based on the discovery of primary impact spherules deposits in NE Mexico and Texas near the base of planktic foraminiferal zone CF1, dated at 170 k.y. before the Cretaceous-Paleogene boundary. A recent study of the most pristine Chicxulub impact spherules discovered on Gorgonilla Island, Colombia, suggested that they represent a primary impact deposit with an absolute age indistinguishable from the Cretaceous-Paleogene boundary. Here, we report on the Gorgonilla section with the main objective of evaluating the nature of deposition and age of the spherule-rich layer relative to the Cretaceous-Paleogene boundary. The Gorgonilla section consists of light gray-yellow calcareous siliceous mudstones (pelagic deposits) alternating with dark olive-brown litharenites (turbidites). A 3-cm-thick dark olive-green spherule-rich layer overlies an erosional surface separating Maastrichtian and Danian sediments. This layer consists of a clast-supported, normally graded litharenite, with abundant Chicxulub impact glass spherules, lithics (mostly volcanic), and Maastrichtian as well as Danian microfossils, which transitions to a calcareous mudstone as particle size decreases. Mineralogical analysis shows that this layer is dominated by phyllosilicates, similar to the litharenites (turbidites) that characterize the section. Based on these results, the spherule-rich layer is interpreted as a reworked early Danian deposit associated with turbiditic currents. A major hiatus (>250 k.y.) spanning the Cretaceous-Paleogene boundary and the earliest Danian is recorded at the base of the spherule-rich layer, based on planktic foraminiferal and radiolarian biostratigraphy and carbon stable isotopes. Erosion across the Cretaceous-Paleogene boundary has been recorded worldwide and is generally attributed to rapid climate changes, enhanced bottom-water circulation during global cooling, sea-level fluctuations, and/or intensified tectonic activity. Chicxulub impact spherules are commonly reworked and redeposited into younger sediments overlying a Cretaceous-Paleogene boundary hiatus of variable extent in the Caribbean, Central America, and North Atlantic, while primary deposits are rare and only known from NE Mexico and Texas. Because of their reworked nature, Gorgonilla spherules provide no stratigraphic evidence from which the timing of the impact can be inferred.


Item Type:Article
Related URLs:
URLURL TypeDescription
https://doi.org/10.1130/b35287.1DOIArticle
Additional Information:© 2019 Geological Society of America. Manuscript Received by the Society 11 March 2019; Revised Manuscript Received 15 March 2019; Manuscript Accepted 29 April 2019. This study was based upon work supported by Princeton University, Geosciences Department Tuttle and Scott funds; and the U.S. National Science Foundation (NSF) through the Continental Dynamics Program and Sedimentary Geology and Paleontology Program under NSF grants EAR-0207407 and EAR-0447171. We thank Alexis Godet and another anonymous reviewer for their comments. We thank Parques Nacionales de Colombia for permission to do field work on Gorgona and Gorgonilla Islands and to take samples from the Gorgonilla Cretaceous-Paleogene section. Special thanks go to Hermann Bermúdez, Liliana Bolívar, and Wolfgang Stinnesbeck for their help during field work in Colombia, and to Julieta Suriano for her insights and feedback on the lithological and sedimentological analyses.
Funders:
Funding AgencyGrant Number
Princeton UniversityUNSPECIFIED
NSFEAR-0207407
NSFEAR- 0447171
Record Number:CaltechAUTHORS:20190621-153144344
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20190621-153144344
Official Citation:Paula Mateo, Gerta Keller, Thierry Adatte, André M. Bitchong, Jorge E. Spangenberg, Torsten Vennemann, Christopher J. Hollis; Deposition and age of Chicxulub impact spherules on Gorgonilla Island, Colombia. GSA Bulletin doi: https://doi.org/10.1130/B35287.1
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:96640
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:22 Jun 2019 12:40
Last Modified:03 Oct 2019 21:24

Repository Staff Only: item control page