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Multi‐scale transgressive–regressive cycles from the mid‐Jurassic were recognised in the Central Lusitanian Basin, Portugal. These cycles allow the depositional evolution of the basin to be better understood and aid in the construction of stratigraphic sequences composed of three hierarchies. The stacking pattern of high‐frequency transgressive–regressive sequences forms larger clusters that define medium‐frequency transgressive–regressive sequences. Likewise, the stacking pattern of medium‐frequency transgressive–regressive sequences generates two Bathonian–early Callovian low‐frequency transgressive–regressive sequences. Integration of several methods supported the interpretation of facies associations representing clastic deposition in offshore to shoreface environments and carbonate sediments in outer to inner ramp settings. New data from calcareous nannofossils and dinoflagellate assemblages constrained the interval's Bathonian–early Callovian age, thus unveiling the Middle–Upper Jurassic disconformity and filling the Middle Jurassic stratigraphic record gap in the Central Lusitanian Basin. This study may be helpful for similar successions in Tethyan domains and comparable depositional settings elsewhere. [ABSTRACT FROM AUTHOR]

The visualization, analysis and interpretation of sedimentary data can be optimized with techniques such as the Digital Outcrop Models (DOMs) generated with the Structure from Motion – Multi-View Stereo (SfM-MVS) technique. In this paper, to demonstrate the usage of DOMs in the characterization of the depositional architecture of a braided fluvial system, we developed a case study in Jaicós Formation, Parnaíba Basin, NE Brazil, where a high-resolution stratigraphic analysis of a braided fluvial system was performed, and the potentials and limitations of the method were evaluated. This multi-scale reservoir analysis allowed the identification, description and interpretation of facies, bounding surfaces and architectural elements. In addition, it was also possible to predict quantitative attributes of the fluvial system that deposited this sequence and evaluate the potential of this formation as a reservoir. • The usage of Virtual Outcrop Models in High Resolution Stratigraphy. • Analysis of facies, bounding surfaces and architectural elements. • Quantitative estimation of the fluvial system that deposited Jaicós Formation. [ABSTRACT FROM AUTHOR]

An integrated approach combining petrography, photogrammetry, geochronology, SEM, and geochemical data was utilized to analyze lithofacies, stacking patterns, and lateral facies variations, and to interpret environmental dynamics during the deposition of carbonates from 'La Barre du Cengle' in the Early Paleogene. Located in the SE of France, the elliptical Cengle Plateau stretches 7 km from east to west and is 2 km wide, featuring cliffs ranging in thickness from 20 to 35 m. These cliffs showcase grayish, beige, and pinkish limestones dominated by palustrine facies, forming part of the 'Calcaire de Saint Marc' Formation of the Arc Basin. Sedimentary deposits within this interval were repeatedly subjected to subaerial exposure due to fluctuations in lake levels driven by climate, resulting in the organization of elementary sequences at decimetric to metric scales, which stack up into small-scale sequences at the decametric order. Deposition occurred under mainly subarid climatic conditions, with paleogeographic variations in the basin corresponding to changes in lake base levels over time and space. At least four frequencies of base level variation are present: very high and seasonal frequency, responsible for the formation of palustrine facies; high frequency, which generates the elementary sequences; medium frequency, which leads to the formation of the small-scale sequences; and low frequency which corresponds to the deposition of the entire set of limestones that form the Cengle cliff. The transition between lacustrine, palustrine, and pedogenic environments consistently occurs from west to east over time. In the more distal regions, the proportion of lacustrine facies tends to increase, and the thicknesses of the preserved sedimentary record tend to be greater. Conversely, palustrine and pedogenic facies predominate in the more proximal areas, typically resulting in decreased thickness. • Lithofacies anatomy reveals environmental dynamics in limestone deposition. • Vertical stacking pattern and lateral variation in lacustrine–palustrine sequences • Cyclical deposition patterns linked to climate-driven lake level fluctuations • Development of an exposure index as an indicator for subaerial exposure duration • Proposal of a model predicting facies & thickness in palustrine-dominated sequences [ABSTRACT FROM AUTHOR]

The sedimentary record of aeolian systems is the result of a complex interplay between the size of the dune and interdune morphologic elements, the rate of bedform migration and the rate of aggradation. Since these parameters are not constant over the time and space, the resulting preserved deposits display a complex architecture characterized by sets of variable thickness and climb angle. Such complexity is observed in both wet and dry aeolian systems of the Pennsylvanian Piauí Formation and is studied here using a numerical reconstruction of the controlling parameters, including dune wavelength and angle of climb each of which varied both spatially and temporally. Through facies analysis and stratigraphic correlation, three genetic units were identified. Spatial variation in the first unit is characterized by a dry aeolian system in which the dimensions of dunes increased to the NW, suggesting deceleration of saturated winds from a dune-field margin to its center. The second and third units are characterized by wet aeolian systems marked by progressively thicker sandsheet deposits and a reduction of dune/interdune thickness ratio. In both units, the spatial variations are marked by a reduction in the dimensions of dunes to the NW, suggesting progressively lower sand availability most likely related to higher water table or its capillary fringe from a dune-field center to its margin. The temporal variation was inferred from the drying-upward cycles observed in all three units. Although the first unit is marked by aeolian cosets overlying thinner simple dune sets, the second and third units are composed by sandsheet deposits at the base overlain by the deposits of progressively larger dunes, in some case culminating with the preservation of aeolian cosets of strata. Such observation suggests that both dry and wet units are marked by an increase in sand saturation allowing the preservation of larger dunes over time. The results of this study suggest a highly dynamic nature of the aeolian dune system where variations in sand supply, availability and wind energy exerted a direct effect on the aeolian system, triggering expansion or contraction of the dune-field. These expansion and contraction phases observed in the Pennsylvanian Piauí Formation are related to glacio-eustatic changes documented during the Pennsylvanian period. [ABSTRACT FROM AUTHOR]