Biostratigraphic and radiometric age data question the Milankovitch characteristics of the Latemar cycles (Southern Alps, Italy)

The combination of age-diagnostic fossils in platform carbonates, geometrical relationships with coeval basinal successions, and single-zircon U-Pb ages from volcaniclastic layers in basinal deposits constrain the age of a cyclic succession in the interior of the Latemar platform to a narrow time span in the Middle Triassic with a duration shorter than 5 m.y. Precession-induced Milankovitch-band sea-level oscillations are therefore excluded as controls for most of the 600 platform cycles reported from Latemar. Statistical evaluation and graphic space-time analyses of cycle stacking patterns alone may therefore not allow an unambiguous recognition of Milankovitch frequencies in ancient platform carbonates.