Special Section: Milankovitch Cycles Through Geologic Time
Repeated subaerial exposure of subtidal carbonate platforms, Triassic, northern Italy: Evidence for high frequency sea level oscillations on a 104 year scale
Article first published online: 4 MAY 2010
Copyright 1986 by the American Geophysical Union.
Volume 1, Issue 4, pages 447–457, December 1986
How to Cite
1986), Repeated subaerial exposure of subtidal carbonate platforms, Triassic, northern Italy: Evidence for high frequency sea level oscillations on a 104 year scale, Paleoceanography, 1(4), 447–457, doi:10.1029/PA001i004p00447., , and (
- Issue published online: 4 MAY 2010
- Article first published online: 4 MAY 2010
- Manuscript Accepted: 22 SEP 1986
- Manuscript Received: 25 APR 1986
Triassic carbonate platforms in northern Italy (Ladinian Latemar, Carnian Durrenstein, Norian Dolomia Principale) consist of hundreds of stacked meter-scale cycles each made of a subtidal unit with a cap rock that carries vadose cements, pisoids, and tepee structures. These diagenetic caps are interpreted to be due to subaerial exposure of the subtidal sediments. The absence of peritidal deposits rules out progradation as the cause of the exposure; i.e., these are not Ginsburg autocycles. Thus the repeated exposure must be the result of relative sea level oscillations, which, based on the number of cycles and time intervals involved, occurred with an average frequency in the 104 -year range. We postulate a combination of small-scale, high-frequency eustasy and local tectonic movements (e.g., differential subsidence in the Norian and infrequent pulses of uplift in the Ladinian) to explain the cyclicity and its internal variations.