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The Central High Atlas of Morocco is a double verging major diapiric province encompassing SW-NE trending salt-related ridges and Lower to Middle Jurassic deposits over synclines (minibasins) in between them. Typically, Pliensbachian and Bajocian platform carbonates flanking diapirs exhibit partial dolomitization in the vicinity of the diapir wall. The interpretation of the diagenetic products and diagenetic evolution of these dolomitized carbonates may be complex due to different fracture patterns, brecciation, fluid pathways, heterogeneities, localized uplift associated with diapiric activity, among others. The present work focuses on the dolomitization affecting Late Aalenian-Bajocian platform carbonates flanking the Tazoult salt wall, localized in the center of the Central High Atlas. Analytical work includes standard microscopy, cathodoluminescence and ¿¿13C¿¿¿18O isotopic analyses. A paragenetic sequence is discussed to reconstruct the diagenetic evolution of the flanking platform carbonates. The results highlight the major influence of diapirism and igneous intrusions on the fluid circulation. Moreover, the present work complements a previous work related to the Liassic successions flanking the Tazoult salt wall.

Salt is playing a principal role in the current energy transition. From diapirs to salt walls, salt structures are being proposed for a growing number of non-fossil energy purposes and carbon- neutral projects (i.e., geothermics, hydrogen storage in salt caverns or CCS). However, diapiric structures are not uniform and exhibit significant compositional and structural heterogeneities that prevent an easy characterization and exploration, thus increasing the risk of exploitation. Compositional heterogeneities within salt structures arise by the occurrence of different rocks inherited from the original Layered Evaporite Sequence (LES) and transported during salt flow or created through various diagenetic processes during diapirism (e.g., caprock formation). One of the most common heterogeneities found in salt bodies is the presence of heterometric rock masses known as stringers. The limestones of the upper Muschelkalk (M3) facies (Middle Triassic) are the primary non-evaporitic lithological unit within the Triassic LES of the South-Central Pyrenees. These limestones are exposed throughout the South-Pyrenean fold-and-thrust belt embedded in mudrocks and gypsums of the Upper Triassic Keuper facies, forming the actual caprock exposures in the region. The Estopanyà salt wall is located in the westernmost part of the South-Central Pyrenean Zone, within the Serres Marginals thrust sheet. This area shows a well- preserved 58 km2 caprock exposure formed by Middle and Upper Triassic rocks that surround two adjacent salt-embedded basins known as the Estopanyà and Boix synclines. According to the stratigraphic record of these synclines, from the Upper Cretaceous to the Oligocene, the evolution of the area resulted in salt withdrawal leading to salt inflation and the occurrence of several E-W- oriented salt walls that were exposed during the deformation onset in the Lower Eocene (early Ypresian times). The M3 stringers in the Estopanyà salt wall are embedded in a caprock matrix fo

The petrophysical and petrothermal characterization of the sedimentary succession of the Oliana anticline in the Southern Pyrenees has been performed on the basis of mineral density, connected porosity, permeability, P-wave velocity and thermal conductivity measurements of rock samples distributed along this anticline. This dataset was used to explain: (I) the variability of petrophysical rock properties along the Oliana anticline, (II) the distribution of thermal conductivity along the sedimentary units of the anticline, (III) the relationships between the fold and petrology concerning the mineral density, connected porosity, permeability, P-wave velocity and thermal conductivity of rocks and (IV) the tectonic and diagenetic controls underlying the observed relationships, as described in the research article: "Petrological, petrophysical and petrothermal study of a folded sedimentary succession: the Oliana anticline (Southern Pyrenees), outcrop analogue of a geothermal reservoir - Global and Planetary Change Journal (2023)¿. This contribution presents here the raw and statistical datasets used to discuss the potential of the Oliana anticline as a geothermal reservoir analogue and also includes an extended methodological section that proposes a new procedure to measure the thermal conductivity of highly heterogeneous coarse-grained sedimentary rocks using the Modified Transient Source Plane (MTPS) method on a TCi C-Therm thermal analyzer. These complete datasets can be used to better discuss and understand the principal limitations of outcrop analogue studies applied to unconventional geothermal reservoirs in foreland basins on the basis of the analysis of rock petrophysical and petrothermal properties. Furthermore, the data obtained in the Oliana anticline can be used to understand the structural, diagenetic and petrological factors that can modify the petrophysical and petrothermal properties of rocks and to discuss the potential of foreland basin margins to be us

The Oliana anticline (Southern Pyrenees) has been characterized as an outcrop analogue of a geothermal reservoir using field data (stratigraphy and fracturing) and petrological, petrophysical and petrothermal analyses. Five lithofacies were established including conglomerates, hybrid arenites, lithic arenites, carbonates and evaporites. Petrophysical measurements indicate widely dispersed values of bulk density, connected porosity, permeability and velocity of compressional acoustic waves. Connected porosity is the factor that mostly influences bulk density, compressional wave velocity and permeability. In turn, diagenetic processes (such as dissolution and cementation) and fracturing, coupled with petrological features such as mineral composition, matrix content and grain size, are the most critical factors controlling rock porosity along the Oliana anticline. Thermal conductivity measures reveal a compositional control on the thermal properties of rocks. Thermal characterization of the structure reveals a low conductive area that matches the carbonate and evaporite succession of the anticline core and a highly conductive zone associated with the detrital succession of the fold limbs. The Oliana anticline has been classified as a petrothermal system due to the low permeability values of the studied sedimentary succession. Despite such classification, this contribution provides a useful exploration tool for future studies of non-conventional geothermal and CO storage sites located in folded sedimentary successions in the proximal domain of foreland basins.

Detailed observations on Venus tessera terrain reveal the presence of tectonic structures, characterized by a subcircular trough, limiting an internal area with the average elevation of the surrounding terrain. We named this new type of tectonic structures Circular Troughs. Here we show the results of a morphometric study and a structural analysis based on data from 609 structures obtained through a global survey on Venus. Circular Troughs have an average outer radius of 12 ± 4.4 km, an average inner radius of 9 ± 3.9 km and an average trough width of 3 ± 1.2 km. A comparison with other tectonovolcanic structures on Venus shows that they are smaller and their size-distribution is more bounded. Although Circular Troughs show morphological similarities with some corona types, their size distribution is significantly smaller than coronae indicating a shallower geodynamic formation process. A shape preferred orientation analysis shows that Circular Troughs in Western Ovda are elongated parallel to long-wavelength tessera folds indicating that they are at least partially deformed by them, thus Circular Trough formation predates or it is contemporary with folding. A detailed structural analysis suggests that they were generated by small scale diapirism exclusively developed in tessera terrain. Several hypotheses could explain this small scale diapirism inside tessera terrain including volcanically driven compositional diapirism, small scale thermal diapirism or compositional cold diapirism, considering that the probable dessication of an ancient ocean would have generated evaporitic deposits in the past later buried by younger geological units.