Carbonate platform deposits record a complex interplay of numerous geodynamic variables, of which eustasy, subsidence, and sediment accumulation are prime factors in determining both the km-scale (depositional sequence-scale) and meter-scale (depositional cycle-scale) stratigraphic packaging. The M. Triassic Latemar platform (740 m thick, 5-6 km wide) provides a seismic-scale outcrop example of an intact carbonate shelf-to-basin transition, ideal for integrating sequence stratigraphy with facies and cyclic stratigraphy. This sub-circular, high-relief buildup records two third-order (1-10 myr) accommodation sequences within the platform interior, the Lower Ladinian Sequence (L1 - 8 myr; 400 m thick) and Upper Ladinian Sequence (L2 - 6 myr; 340 m thick). Sequence 1 developed atop a widespread, low-relief M. Anisian carbonate bank (60 m thick). Underlying subtidal bank cycles thin upward into the basal, subaerial sequence boundary (Type 1) reflecting decreasing third-order accommodation, and above it platform-interior facies of sequence L1 retrograde. This results in superimposition of Ladinian basinal and foreslope facies atop the underlying, horizontal, shallow-water bank along its periphery. The transgressive (TST) and highstand systems tract (HST) of sequence L1 (as well as L2) are marked by long-term, systematic vertical facies changes (subtidal- vs. exposure-dominated facies) and variation in stacking patterns of aggradational high-frequency, 20 kyr cycles (progressive thickening- vs. thinning-upward) within the platform interior. The maximum flooding surface (MFS) is a marine hardground surface displaying evidence of very slow sedimentation and is the platform expression of the condensed section. A type 2 SB caps sequence L1, marked by an interval of vertically superimposed thin subaerial tepees; beneath this, high-frequency cycles are thinning upward, and above they are thickening-upward. Only the transgressive systems tract of sequence L2 is preserved at the Latemar owing to Late Ladinian-Early Carnian volcanism and tectonism, which terminated carbonate platform deposition.

This study examines, in particular, the concept of composite eustasy, that is, superimposed sea level fluctuations with different frequencies (defined as orders) and different amplitudes, and the role it plays in the linkage between meter-scale cyclic stratigraphy and km-scale sequence stratigraphy. The results of this work suggest that there exists a hierarchy of stratigraphic forcing driven by composite eustasy that results in organized stacking patterns (thickness, subfacies character, early diagenetic attributes) of high frequency, typically fourth- and fifth-order, shallow-water carbonate cycles dictated by low frequency, third-order relative sea level effects. This study suggests that systematic vertical changes in stacking patterns of high frequency cycles across a larger depositional sequence is due to systematic and predictable differences

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in depositional space available during the rising and falling stages of a relative third-order sea level change. This work also suggests that these systematic variations in cycle stacking patterns will exist regardless of the mechanism responsible for generating the high-frequency cycles, be it an autocyclic or allocyclic mechanism. This approach has major implications for the use of high frequency, fourth- and fifth-order cycle characteristics to identify third-order cycles in outcrops and cores of shallow water carbonates, where stratigraphic control may be less than desirable. This would constitute a valuable bridge between cyclic stratigraphy at the meter scale and sequence stratigraphy at the seismic scale.

The Alpine Triassic Ladinian Latemar buildup is a spectacular example, wherein a systematic succession of high-frequency cycle stacking patterns and early diagenetic features exists within an overriding third-order cycle (sequence) reflecting the interplay of short-term, high-frequency (fourth, fifth order) eustasy and long-term, low-frequency (third order) eustasy in accordance with the hierarchy of stratigraphic forcing. Central to the interpretation of these examples is the demonstration that true eustatic rhythms are recorded in the high-frequency cyclicity, as verified by time modeled by computer under conditions of constant lag depth-dependent sedimentation, uniform subsidence, and composite eustasy. An understanding of composite relative sea level changes and the potential for a hierarchy of stratigraphic forcing provides the link between cyclostratigraphy and sequence stratigraphy, and also has important implications regarding the stratigraphy of early diagenesis.

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