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Sedimentological and paleoenvironmental scenario before, during, and after the Messinian Salinity Crisis: The San Miguel de Salinas composite section (western Mediterranean) Highlights 1) The sedimentary record is divided into three synthems: Messinian I (pre-evaporitic), Messinian II (syn-evaporitic), and Pliocene (post-evaporitic). 2) Marls associated with gypsum beds (syn-evaporitic phase) record dwarf planktonic foraminifera. 3) The syn-evaporitic phase (chron 3Cr) records major changes in water salinity in a stressed marine environment. 4) Two erosional surfaces correspond to the intra-and end-Messinian unconformities. 5) The end-Messinian unconformity is represented by an incised paleovalley.

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The historical quarry of the Nueva Tabarca fortress (Mediterranean Sea, SE of Spain) was developed in a complex sedimentary Miocene deposit. Five lithostratigraphic units have been defined, including different lithologies such as breccias and microconglomerates (Unit 1), massive and laminated lithoarenites (Units 1, 3 and 5), calcarenites and biocalcirudites (Units 2 and 4). A complete stratigraphic description of this sequence has been carried out, as well as the petrophysical characterization of the most significant lithologies including the analysis of rock durability as well as hydraulic and mechanical properties. Regarding durability, the softest rocks correspond to those from the Unit 4, whilst samples from Units 2 and 5 are the most durable. Three weathering patterns were observed during the artificial ageing test according to both the velocity and intensity of the sample decay. Each pattern is explained according to water-circulation possibility through the rock, its porous system, and the mechanical strength. Rock weathering in monuments of Nueva Tabarca is quantified and discussed according to the results found in the laboratory. Several decay forms are observed in the building stones (mainly differential erosion, alveolization, and rounding forms). Both 3D photogrammetric and 3D geological model of the historical quarry were elaborated in order to quantify the extracted volume of building stones, differentiating the specific quarried percentage of each lithology. Correlation between the results obtained in the volumetric analysis of the historical quarry and the building stones used in the monuments has been carried out. 3D models were also used for determining the remaining rock volume in the current outcrops. Finally, a set of recommendations for future conservation works of the architectural heritage are proposed after the current availability of the different rock varieties and their petrophysical behaviour.

Among smart materials, self-healing is one of the most studied properties. A self-healing polymer can repair the cracks that occurred in the structure of the material. Polyketones, which are high-performance thermoplastic polymers, are a suitable material for a self-healing mechanism: a furanic pendant moiety can be introduced into the backbone and used as a diene for a temperature reversible Diels-Alder reaction with bismaleimide. The Diels-Alder adduct is formed at around 50 °C and broken at about 120 °C, giving an intrinsic, stimuli-responsive self-healing material triggered by temperature variations. Also, reduced graphene oxide (rGO) is added to the polymer matrix (1.6–7 wt%), giving a reversible OFF-ON electrically conductive polymer network. Remarkably, the electrical conductivity is activated when reaching temperatures higher than 100 °C, thus suggesting applications as electronic switches based on self-healing soft devices.