Lúcio, Thales and Souza Neto, João Adauto and Selby, David (2020) 'Late Barremian / Early Aptian Re–Os age of the Ipubi Formation black shales : stratigraphic and paleoenvironmental implications for Araripe Basin, northeastern Brazil.', Journal of South American earth sciences., 102 . p. 102699.
The Ipubi Formation of the Santana Group, Araripe Basin, Brazil, is characterized by black shales and overlying evaporite deposits and is suggested to record the transition from lacustrine to marine depositional environments. To date, the age of the black shales, constrained only by microfossils, is poorly determined, with ages spanning ∼25 myrs from 125 to 100.5 Ma (Aptian-Albian). Here we present new Re–Os elemental and isotopic data to provide the first absolute age for those rocks of the Ipubi Formation and an improved understanding of the depositional paleoenvironment of the Araripe Basin. The Re–Os isotope data for Ipubi Formation black shales yields a depositional age of 123 ± 3.5 Ma, with a highly radiogenic initial 187Os/188Os composition (Osi) of 1.97 ± 0.02. The Re–Os age indicates that the deposition of the Ipubi Formation black shales occurred during the Late Barremian/Early Aptian, prior to the onset of OAE 1a, in a highly restricted marine/lacustrine setting.
|Full text:||Publisher-imposed embargo until 18 June 2021. |
(AM) Accepted Manuscript
Available under License - Creative Commons Attribution Non-commercial No Derivatives.
File format - PDF (11090Kb)
|Publisher Web site:||https://doi.org/10.1016/j.jsames.2020.102699|
|Publisher statement:||© 2020 This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/|
|Date accepted:||09 June 2020|
|Date deposited:||18 June 2020|
|Date of first online publication:||18 June 2020|
|Date first made open access:||18 June 2021|
Save or Share this output
|Look up in GoogleScholar|