Middle Triassic carbonate buildups of the Dolomites were high in relief (500–1000m) and small in size (one to a few square kilometres in area). A paradox results from the carbonate platform model that invokes the platform top, including reef rims, as the carbonate factory and flanking beds as talus deposits. Most buildups consist largely of clinoforms (inclined at 10‐50°) whereas massive reef rocks and stratified buildup interiors are poorly developed or absent. Facies and modal analysis of 323 thin sections from buildups of the Marmolada indicate that clinoforms are: (i) predominantly composed of in situ boundstones (56% of all samples); (ii) primarily made up of early cements (37 vol.%), microbial crusts (17 vol.%), micritic intraclasts (10 vol.%) and Tubiphytes (8 vol.%); and (iii) contain diagnostic shallow water grains (dasyclads, coated grains) that are less abundant by 1‐2 orders of magnitude compared with buildup interior facies. These data suggest that the clinoforms themselves were the main carbonate factory of the Triassic buildups. Stratified buildup interior rocks and massive reef rocks were apparently not a prerequisite for buildup growth and clinoform progradation.

This article is the first part of an integrated study to characterize the anatomy and geometries of carbonate shoal reservoir bodies in epicontinental settings. It is based on outcrop analog data from Triassic layer-cake carbonates in the south German Basin, which were deposited along an epicontinental, very gently inclined carbonate ramp. The database of this study consists of 56 measured sections supplemented by six shallow cores and wireline logs, covering an area of 25 by 36 km (15 by 22 mi). The potential reservoir bodies consist generally of midramp shoal and shoal-fringe facies types, which are composed of skeletal and oolitic carbonate packstones and grainstones with significant amounts of porosity. The upper Muschelkalk is composed of a lower transgressive and an upper regressive interval; within these, shoal bodies show not only similarities but also major differences in character, geometry, and distribution. These reflect the conditions of an epeiric system, which reacts strongly to small changes in accommodation. The accommodation seems to be mainly triggered by the interaction of hierarchically organized large-, medium-, and small-scale relative sea level changes and a subtle paleorelief. At the level of medium-scale cycles, distinct two-dimensional cyclicity styles can be differentiated, which record the lateral facies distribution along the depositional gradient. Different styles of medium-scale cycles include different types of shoal bodies: (1) transgressive crinoidal shoal style:

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As a result of a phase of extensional tectonics in the western Tethyan region, a horst and graben topography formed during the Middle Triassic (Ladinian) in northern Italy. Horsts were sites of shallow water carbonate sedimentation, while pelagic and volcaniclastic sediments were deposited in the grabens. Two carbonate platforms approximately 500 m thick can be distinguished in the Marmolada area of the Dolomites: the Marmolada platform proper, which covered an area of 6 km2, and the Costabella platform, which extended for about 12 km in a NW‐SE direction and was about 3 km across. The facies of these isolated platforms reflect the influence of storms from the SW. Windward platform margins were characterized by a marine sand belt of skeletal and aggregate grainstones with a dominant platform directed cross‐stratification. The central portions of the platforms were occupied by supratidal sand cays which are made up of storm washovers. Leeward parts of the platforms are composed of shallow subtidal sand flat deposits. Laterally discontinuous reefs chiefly composed of various calcareous algae are developed at the outer margins of the platforms. Along windward margins, reefs may form a belt several hundred metres wide; along leeward margins their width is commonly reduced to some tens of metres. Foreslope talus breccias surround the platforms. Clinoform bedding showing basinward dips of 30°‐40° is typical of this facies belt, which is approximately 2 km wide. Basinal sediments, only some tens of metres thick, are radiolarian micrites. Abundant sediment‐gravity‐flow deposits expand the basinal sequence at the toes of windward margins and were probably triggered by storm return flows. Synsedimentary faults striking both NNE‐SSW and NW‐SE separate the bedded platform limestones from flank deposits and reefs. They account for the stationary nature of the platforms. Neptunian dykes show preferred NNE‐SSW and E‐W trends. Sinistral displacements are associated with NW‐SE trending faults. Depressions in the basins, filled with red, turbiditic pelagic sediments, show N‐S trends and are probably compressional in origin. The structural pattern may have resulted from oblique, NW‐SE oriented extension of the E‐W trending Middle Triassic graben zone of the Dolomites. In the Ladinian of the Dolomites, the stationary platform type can be distinguished from a retrograding type, whereas continuously prograding platforms apparently did not develop.

Subsurface data from northern interior Oman and new surface data from the Oman Mountains imply that the north Oman passive continental margin developed in the Permian. Late Carboniferous and Permian updoming of an area roughly overlapping the present Oman Mountains is indicated by the northward thinning of the continental clastics of the Haushi Group (Late Carboniferous and Early Permian) in the sub-surface. Well correlations show the thinning as cutouts at internal unconformities proving contemporary uplift along a roughly E-W strike. Deep water sedimentation off northern Oman commenced already in the early Late Permian. Permian deep water sediments of the Hawasina nappes consist of reef-derived sediment gravity flow deposits, cephalopod limestones and radiolarites that were deposited in a slope and basin floor environment north of a coralgal reef tract. Mafic volcanics underlying these deposits show locally tholeiitic characters suggesting that incipient drifting of the Hawasina ocean occurred as early as the Late Permian. Penecontemporaneous flooding of the Arabian shield occurred on an almost unfaulted substratum even in areas close to the inferred shelf edge. The interpretation of these data in terms of models for continental rifting suggests that north Oman developed on the little faulted side of an asymmetrical rift produced by Permo-Carboniferous low-angle normal faulting of the lithosphere.