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1.
Data Brief ; 24: 103904, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31193225

RESUMO

Litho- and biostratigraphic data are provided of 5 stratigraphic sections in Romania covering the "Badenian" marine flooding that occurred in the Central Paratethys during the middle Miocene (Langhian). The dataset includes stratigraphic logs and descriptions of the profiles, and biostratigraphic analyses on calcareous nannofossils and foraminifera. In addition, characteristic stratigraphic features and representative fossils, including tiny Streptochilus foraminifera in the Campinita section in the SE Carpathian Foredeep, are presented in photographs. The data show that the flooding is characterized by the sudden abundance of Langhian calcareous nannofossils and foraminifera with a strong Mediterranean affinity.

2.
Science ; 320(5875): 500-4, 2008 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-18436783

RESUMO

Calibration of the geological time scale is achieved by independent radioisotopic and astronomical dating, but these techniques yield discrepancies of approximately 1.0% or more, limiting our ability to reconstruct Earth history. To overcome this fundamental setback, we compared astronomical and 40Ar/39Ar ages of tephras in marine deposits in Morocco to calibrate the age of Fish Canyon sanidine, the most widely used standard in 40Ar/39Ar geochronology. This calibration results in a more precise older age of 28.201 +/- 0.046 million years ago (Ma) and reduces the 40Ar/39Ar method's absolute uncertainty from approximately 2.5 to 0.25%. In addition, this calibration provides tight constraints for the astronomical tuning of pre-Neogene successions, resulting in a mutually consistent age of approximately 65.95 Ma for the Cretaceous/Tertiary boundary.

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