Frequency modulation reveals the phasing of orbital eccentricity during Cretaceous Oceanic Anoxic Event II and the Eocene hyperthermals

0458676 - GFÚ 2017 RIV NL eng J - Článek v odborném periodiku
Laurin, Jiří - Meyers, S. R. - Galeotti, S. - Lanci, L.
Frequency modulation reveals the phasing of orbital eccentricity during Cretaceous Oceanic Anoxic Event II and the Eocene hyperthermals.
Earth and Planetary Science Letters. Roč. 442, 15 May (2016), s. 143-156. ISSN 0012-821X. E-ISSN 1385-013X
Grant CEP: GA MŠMT LH12041
Institucionální podpora: RVO:67985530
Klíčová slova: orbital eccentricity * cyclostratigraphy * Cenomanian
Kód oboru RIV: DB - Geologie a mineralogie
Impakt faktor: 4.409, rok: 2016

Major advances in our understanding of paleoclimate change derive from a precise reconstruction of the periods, amplitudes and phases of the ‘Milankovitch cycles’ of precession, obliquity and eccentricity. While numerous quantitativeapproaches exist for the identification of these astronomical cycles in stratigraphic data, limitations in radioisotopic dating, and instability of the theoretical astronomical solutions beyond ∼50 Myr ago, can challenge identification of the phase relationships needed to constrain climate response and anchor floating astrochronologies. Here we demonstrate that interference patterns accompanying frequency modulation (FM) of short eccentricity provide a robust basis for identifying the phase of long eccentricity forcing in stratigraphic data. One-and two-dimensional models of sedimentary distortion of the astronomical signal are used to evaluate the veracity of the FM method, and indicate that pristine eccentricity FM can be readily distinguishedin paleo-records. Apart from paleoclimatic implications, the FM approach provides a quantitative technique for testing and calibrating theoretical astronomical solutions, and for refining chronologies for the deep past.

Trvalý link: http://hdl.handle.net/11104/0258918