The 720-m-thick succession of the Middle Triassic Latema Ár Massif (Dolomites, Italy) was used to reconstruct the lagoonal facies architecture of a small atoll-like carbonate platform. Facies analysis of the lagoonal sediments yields a bathymetric interpretation of the lateral facies variations, which re¯ect a syndepositional palaeorelief. Based on tracing of lagoonal¯ooding surfaces, the metre-scale shallowing-upward cycles are interpreted to be of allocyclic origin. Short-term sea-level changes led to subaerial exposure of wide parts of the marginal zone, resulting in the development of a tepee belt of varying width. Occasional emergence of the entire lagoon produced lagoon-wide decimetrethick red exposure horizons. The supratidal tepee belt in the backreef area represented the zone of maximum elevation, which circumscribed the sub-to peritidal lagoonal interior during most of the platform's development. This tepee rim, the subtidal reef and a sub-to peritidal transition zone in between stabilized the platform margin. The asymmetric width of facies belts within individual metre-scale cycles was caused by redistribution processes that re¯ect palaeowinds and storm paths from the present-day south and west. The overall succession shows stratigraphic changes on a scale of tens of metres from a basal subtidal unit, overlain by three tepee-rich intervals, separated by tepee-poor units composed of subtidal to peritidal facies. This stacking pattern re¯ects two third-order sequences during the late Anisian to early middle Ladinian.

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Basic shallowing‐upward cycles (shu‐cycles) and five‐bundled megacycles in the Latemar platform have been widely regarded as a model example for precessional and eccentricity forcing in the Mesozoic. Based on bio‐/chronostratigraphic data, recent studies questioned this particular type of Milankovitch forcing on the Latemar cyclic series. We present an integrated model that incorporates (i) new cyclostratigraphic data, (ii) new and existing bio‐/chronostratigraphic data and (iii) new spectral analyses. The basic shu‐cycles in the Latemar reflect sub‐Milankovitch control. Cycle bundles of 1 : 4–5 (megacycles : shu‐cycles) indicate precessional forcing. They do not reflect eccentricity superimposed on precessional forcing. Spectral analyses reveal highly significant ratios in the large‐scale cycle bundlings. Stacking patterns of 1 : 9.9 and 1 : 24.0 shu‐cycles represent obliquity and short eccentricity forcing. Both sub‐Milankovitch and Milankovitch forcing potentially controlled shallow subtidal carbonate deposition in Mesozoic greenhouse times. Cyclostratigraphic models require an integrated approach including bio‐ and chronostratigraphic data.

Sedimentary cycles recorded in young sediments are often attributed to fluctuations of the Earth's climate on a 104−106‐year scale which in turn is governed by periodic variations in solar insolation linked to orbital (Milankovitch) parameters. A spectacular example of cyclic stratal patterns in ancient deposits is the Middle Triassic Latemar carbonate platform (W Dolomites, N Italy). Based on spectral analyses from previous studies, a superimposition of precession (∼20 ka) and eccentricity (∼100 ka) controlled sea‐level fluctuations has been suggested to account for the stacking hierarchy at Latemar, with ∼20 ka being assigned to each highest‐order depositional cycle. Zircon U–Pb isotopic ages from volcanic‐ash layers within the cyclic succession, corroborated by biostratigraphic constraints, suggest that the average time interval for every individual cycle is significantly smaller than the shortest Milankovitch period and therefore challenge previously published interpretations relating distinct spectral peaks to the above mentioned hierarchy. However, our new spectral data indicate that cyclicities resembling Milankovitch characteristics might exist, but on an entirely different scale. Our findings show that frequency spectra should only be interpreted in combination with robust age control. They also encourage the search for complementary mechanisms controlling carbonate deposition.

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