 |
| Titel |
Astronomical calibration of the geological timescale: closing the middle Eocene gap |
| VerfasserIn |
T. Westerhold, U. Röhl, T. Frederichs, S. M. Bohaty, J. C. Zachos |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1814-9324
|
| Digitales Dokument |
URL |
| Erschienen |
In: Climate of the Past ; 11, no. 9 ; Nr. 11, no. 9 (2015-09-23), S.1181-1195 |
| Datensatznummer |
250117404
|
| Publikation (Nr.) |
 copernicus.org/cp-11-1181-2015.pdf |
|
|
|
|
|
| Zusammenfassung |
| To explore cause and consequences of past climate change, very accurate age
models such as those provided by the astronomical timescale (ATS) are
needed. Beyond 40 million years the accuracy of the ATS critically depends on
the correctness of orbital models and radioisotopic dating techniques.
Discrepancies in the age dating of sedimentary successions and the lack of
suitable records spanning the middle Eocene have prevented development of a
continuous astronomically calibrated geological timescale for the entire
Cenozoic Era. We now solve this problem by constructing an independent
astrochronological stratigraphy based on Earth's stable 405 kyr eccentricity
cycle between 41 and 48 million years ago (Ma) with new data from deep-sea
sedimentary sequences in the South Atlantic Ocean. This new link completes
the Paleogene astronomical timescale and confirms the intercalibration of
radioisotopic and astronomical dating methods back through the
Paleocene–Eocene Thermal Maximum (PETM, 55.930 Ma) and the
Cretaceous–Paleogene boundary (66.022 Ma). Coupling of the Paleogene
405 kyr cyclostratigraphic frameworks across the middle Eocene further paves
the way for extending the ATS into the Mesozoic. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|