Reconnaissance reassessment of the Late Eocene Oceanic unit, Barbados: microtektite geochemistry, zircon U-Pb geochronology, micropaleontology, and provenance.
- Author(s)
- J. Weber, Benjamin Wilson, Christian Koeberl, P. O'Sullivan, R. Donelick, E. S. Posner
- Abstract
We measured stratigraphic sections and collected samples from Oceanic suite outcrops at Gay’s Cove and Bath Cliffs, Barbados, in order to restudy the late Eocene microtektite layer(s) and provide new geological context. We disaggregated and processed samples into separates of microfossils, microtektites, and heavy minerals, and we present up-to-date glass geochemistry, biostratigraphic analysis, and detrital zircon U-Pb analysis. Results from the new Barbadian microtektite glass chemistry analysis (Gay’s Cove) compare well with those from other published microtektite analyses, as well as those from the correlative North American strewn field.
Cove. Using U-Pb, we dated 24 Tertiary zircon grains, probably from volcanic ash-fall events, which at Gay’s Cove yielded a preliminary, poorly defined, and incorrect depositional age for the microtektite layer (≤31.84 ± 0.85 Ma; weighted mean of only three grains). Three additional new U-Pb depositional ages (≤38.52 ± 1.0 Ma, ≤39.23 ± 0.3 Ma, ≤35.25 ± 0.82 Ma) were obtained from bottom to top in the 24 m section at Bath Cliffs. We also dated 46 Paleozoic–Proterozoic zircon grains using U-Pb and discuss whether these “old” grains represent recycled (subducted and extruded) volcanic grains or windblown silt/sand from Africa.
- Organisation(s)
- Department of Lithospheric Research
- External organisation(s)
- Grand Valley State University, University of the West Indies, St. Augustine, GeoStep Services, Apatite.com Partners LLC, Naturhistorisches Museum Wien (NHM)
- Volume
- 542
- Pages
- 333-346
- No. of pages
- 14
- DOI
- https://doi.org/10.1130/2019.2542(17)
- Publication date
- 09-2019
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105105 Geochemistry
- ASJC Scopus subject areas
- Geology
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/c312a672-05d4-46ac-8176-ecc92833b65b