loading page

Secular resonance transitions in the late Cretaceous and astronomical imprints during the Oceanic Anoxic Event II (Schill Grund Platform, North Sea, Offshore Netherlands)
  • +2
  • Michiel Arts,
  • Anne-Christine da Silva,
  • Geert-jan Vis,
  • Daan Beelen,
  • Frits Hilgen
Michiel Arts
universite de Liege

Corresponding Author:[email protected]

Author Profile
Anne-Christine da Silva
Liege university
Author Profile
Geert-jan Vis
TNO Geological Survey Netherlands
Author Profile
Daan Beelen
Utrecht University
Author Profile
Frits Hilgen
Utrecht University
Author Profile


The Chalk Group deposited on the Schill Grund Platform in Dutch offshore comprises a near complete early Danian to late Cenomanian chalk succession. Such a long record (~30 Myrs) allows for the study of long period (>1 Myr) astronomical cycles providing insights into amplitude modulation of astronomical cycles. A 405kyr eccentricity-based tuning was created for one gamma-ray log and one thorium well-logs which go through the Chalk Group. These results were tuned to astronomical solution La2010d, which were then be used to study aspects of long period astronomical cycles. Firstly, the amplitude modulation of the 405 kyr eccentricity by long period astronomical cycles was studied, which indicates that secular resonance transitions took place at ~85 Ma and ~92 Ma. The secular resonance transition at ~92Ma shifted the duration of the 2.4 Myr eccentricity cycle to a 1.2 Myr period while the resonance transition at ~85 Ma shifted the period shifted back 2.4 Myr. The amplitude modulation records were also compared to the amplitude modulation records of astronomical solutions. None of the astronomical solutions accurately model the observed resonance transition. The second result is related to Ocean Anoxic Event II (OAEII). The 2.4 Myr cycle is at a maximum ~ 400kyr before the onset of OAEII and progressively transitions towards a minimum during OAEII, as the 1.2 Myr obliquity cycle peaks during OAEII. This phase relationship between these astronomical cycles leads to a progressive increase in the contribution of the obliquity to the astronomical-insolation signal during OAEII.