Comments on the EXXON cycle chart for the Cretaceous system

Correlation between the various columns of chronostratigraphy on the EXXON chart has often been assumed without being tested. A considerable number of the tie-lines can be shown to be wrong. As a result one cannot know what many of their ‘3rd order cycles ’ refer to in the stratigraphical column. In most examples where such cycles of sea-level change can be dated, somebody else has aíready recognised them. Most of their ‘2nd order cycles ’ are suspect. Paradoxically, current research shows that changes of sea-level through intervals of a few million years may have been simultaneous in Europe and the USA to an accuracy of ±100,000years. Key-Words: EXXON chart, Brd order cycles, 2nd order cycles, Cretaceous, custasy, sea-level changes, accuracy in correlation