Sequence stratigraphy and systems tract development of the Latemar platform, Middle Triassic of the dolomites: Outcrop calibration keyed by cycle stacking patterns
- Exxon Production Research Co., Houston, TX (United States)
- Univ. of Wisconsin, Milwaukee (United States)
- Johns Hopkins Univ., Baltimore, MD (United States)
The Middle Triassic Latemar platform 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 subcircular, high-relief buildup records two third-order accommodation sequences within the platform interior: the lower Ladinian sequence and the upper Ladinian sequence. Sequence L1 developed atop a widespread, low-relief Middle 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; 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 and variation in stacking patterns of aggradational high-frequency, 20 kyr cycles 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.
- OSTI ID:
- 5739498
- Report Number(s):
- CONF-910403-; CODEN: AABUD
- Journal Information:
- AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 75:3; Conference: Annual meeting of the American Association of Petroleum Geologists (AAPG), Dallas, TX (United States), 7-10 Apr 1991; ISSN 0149-1423
- Country of Publication:
- United States
- Language:
- English
Similar Records
Termination of carbonate platforms: Eustatic fluctuations in base level
Superimposed platform carbonate cycles