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A peculiar aspect of Apulia beaches sand is the occurrence of important amounts of heavy silicate minerals (mainly pyroxenes, garnets and amphiboles), forming thin, dark layers and placers interbedded with the dominant light carbonaticlastic fraction. A granulometric, compositional and microanalytical study was carried out on the sand of the beaches stretched along the Gulf of Manfredonia to the Otranto promontory, in order to detail provenance and dispersion of the heavy silicate sandy fraction. The rocks outcropping along the Apulia coast are mainly represented by the limestones of the Mesozoic platform of the foreland domain and by the Plio- Pleistocenic sedimentary covers. The origin of the silicate minerals cannot therefore be found in the rocks outcropping in the area, but must be related to a more distant source. The Ofanto river, whose mouth is in the Gulf of Manfredonia, is the main stream feeding the Apulia coast with sediments eroded by the southern Apennines units and the Mt. Vulture volcano. The microanalitical study revealed that the composition of the pyroxene, melanite garnets and Mg-hastingsite amphiboles is identical to that of the same minerals found in the sediments along the Ofanto river and occurring inside the volcanic bedrock of Mt. Vulture. A minor population of colorless grains of garnets can be probably related to the recycling processes from the Oligo-Miocene sandstones of Southern Apennine terrains. Heavy detrital minerals shed by Vulture edifice source rocks have been found in the sandy fraction dispersed along both northward and southward of the Ofanto mouth. This is in accordance with main longshore current depositing them in the Gulf of Manfredonia. Part of the sands, however, is transported southward by the littoral currents of the Adriatic Sea. The sandy heavy minerals fraction in the is not constant along the coastline. The highest contents are in the northern sector, from the Gulf of Manfredonia to Trani, while they almost disappear in the central sector between Molfetta (BA) and Torre Canne (BR). South of Posticeddu (BR) the amount of heavy minerals increases again, though being always subordinate to the carbonaticlastic fraction. These variations are correlated to the coast physiography: the northern and southern sectors are characterized by a larger platform with a wide surf zone and low energy of the waves, while in the central sector a narrower platform is responsible of a higher energy environment, preventing the deposition of the heavy fraction. A coarser grain size also characterizes the beaches of this sector. At a smaller scale, local variations in the heavy minerals abundances are also related to erosional processes due to anthropic factors: an example is the harbor of Margherita di Savoia (BT), which eastern pier obstacles the northward transport of the Ofanto sediments. The beach southward of the pier has relatively low heavy mineral percentages, while northward the carbonate erosion indirectly causes an enrichment in this component.

During the Messinian, the southern Apennines thrust belt experienced a period of strong tectonic rearrangement and accretion, activation of overthrusts, and consequent migration of depocenters. The upper Miocene successions cropping out in the northern segment of the southern Apennine thrust belt have good potential for improving our understanding of the interplay between Messinian salinity-crisis events and foreland-basin evolution. The local Messinian stratigraphy includes: (1) pre-evaporitic thin-bedded euxinic marly clay, interbedded with diatomaceous marls, (2) evaporitic limestone, crystalline gypsum. and reworked gypsum; (3) post-evaporitic deposits subdivided into two main units: the Torrente Fiumarella unit and the Anzano Molasse Formation that grade upward into ostracod-rich deposits (Lago-Mare facies). The evaporitic and post-evaporitic sequences are separated by an angular unconformity, This paper deals with the stratigraphic and petrographic study of the post-evaporitie deposits. The Torrente Fiumarella unit includes lacustrine and alluvial conglomerates, quartzolithic sandstones containing abundant carbonate detritus, shale, and reworked elastic gypsum. The Anzano Molasse Formation includes thick-bedded deltaic to turbiditic conglomerates and sandstones passing upward to thin-bedded turbidite sandstones and marly-clayey siltstones. Sandstones are quartzofeldspathic with variable proportions of sedimentary (both carbonate and siliciclastic) and plutonic detritus. In particular, two populations are present, plutonic-rich and mixed plutonic-sedimentary. Volcaniclastic layers, composed of dominantly vitric particles (shards and pumice), are also interbedded within Anzano Molasse sandstones. The Anzano succession includes rare freshwater ostracods that increase in abundance in the uppermost Lago-Mare facies. The Lago-Mare facies deposits are represented by silty-marly clay with abundant Ostracoda shells (Ilyocypris gibba, Cyprideis torosa and Candona sp.) and intrarenite having abundant intrabasinal carbonate particles (ooids, peloids, and bioclasts) and subordinate extrabasinal noncarbonate and carbonate particles. The post-evaporitic sequences represent all infilled foredeep basin, with a laeustrine environment progressively deepening and experiencing gravity resedimentation. Detrital modes document complex provenance relations from upper Messinian accreted terranes of the southern Apennines thrust belt. Post-evaporitic sandstones in the Irpinia-Daunia sector of the southern Apennines foreland-basin system record both the effects of the foreland tectonic evolution and the Messinian Mediterranean salinity crisis. They may represent alternative models for foreland-basin evolution during a restricted time in late Messinian, which call be applicable also in other portions of the circum-Mediterranean orogen.

[EN] The intraplate Cameros rift basin in the north of Spain was formed came into being between the Tithonian and the Early Albian and contains 9 000 m of mostly continental sediments. This basin is a good example of cyclicity of different depositional sequences (DSs) in sedimentary environments, which show clear repetition in their sandstone composition (petrofacies) and diagenetic patterns. The DSs are arranged in two megasequences (MSs) separated by a tectonic unconformity. A similar vertical sandstone compositional evolution, subdivided into two stages that repeat cyclically, has been recognised in both MSs: the first comprises quartzo-sedimentolithic petrofacies and the second is made up of several quartzo-feldspathic petrofacies. This was caused by a progression from the recycling of the pre-rift sedimentary cover to the erosion of the mainly plutonic and metamorphic crystalline basement. These changes in the erosion of the different source areas were conditioned by the tectonics of the basin. Furthermore, the original sandstone framework composition conditioned the diagenetic pattern of the two stages: quartzo-sedimentolithic sandstones containing large amounts of very pervasive carbonate cement that reduce their original porosity considerably, and quartzo-feldspathic petrofacies with a rigid framework that maintained the original pores during burial diagenesis. This compositional and diagenetic pattern is probably applicable to other non-volcanic rifted basins, depending upon the original amount of carbonate rock fragments present., [ES] La cuenca intraplaca de rift de Cameros se localiza al norte de España. Se desarrolló entre el Titónico y el Albiense Inferior, depositándose 9000 m de sedimentos fundamentalmente continentales. La cuenca es un buen ejemplo de ciclicidad en los medios sedimentarios en las diferentes Secuencias Deposicionales (SD), lo que genera una clara repetición de la composición de las areniscas (petrofacies) y de las pautas diagenéticas. Las SD están organizadas en dos megasecuencias (MS) separadas por una discordancia de carácter tectónico. Ambas MS presentan una evolución vertical similar en la composición de las areniscas, generando una repetición de dos estadios: (1º) constituido por una petrofacies cuarzosedimentolítica y (2º) formado por varias petrofacies cuarzofeldespáticas. Este hecho viene motivado por el cambio desde la erosión de una cobertera sedimentaria pre-rift a la erosión del basamento cristalino, principalmente constituido por áreas fuente plutónicas y metamórficas. Estos cambios en la erosión de distintas áreas fuente están controlados por la tectónica de la cuenca. Además, la composición original del esqueleto de las areniscas condiciona el tipo de diagénesis para los dos estadios anteriormente descritos: las areniscas cuarzosedimentolíticas contienen abundante cemento de carbonato, que reduce su porosidad inicial drásticamente. Sin embargo, las areniscas cuarzofeldespáticas presentan un esqueleto más rígido que mantiene los poros originales durante la diagénesis de enterramiento. Este patrón composicional y diagenético es probablemente aplicable a otras cuencas de rift intraplaca no volcánicas, dependiendo de la cantidad inicial de fragmentos de roca carbonática.

Three key sand petrofacies (fluvial and marine), derived from the Betic mountain belt, reflect the main clastic contribution of known source rocks, and the complex factors operating during pedogenesis, erosion, transport, deposition (first order parameters). These first order parameters are not independent but influenced by tectonics and climate.

Chemical weathering is the main sand producer within the regolithic environment in northern Calabria. In addition, rapid erosion resulting from steep slopes remove weathered products, and rapid and short transport leads to minimal sediment maturation.

The effects of weathering in a Mediterranean climate on the mineralogy and microfabric of Paleozoic gneiss of the Sila Massif have been studied. The determination of quantitative micropetrographic indices provides a measure of the various stages of weathering.

This review focuses on the recognition of volcanic ash occurrences in marine sediment cores and on using their appearance and properties to deduce their origin. Widespread marine tephra layers are important marker horizons for both volcanological as well as general geological investigations. We describe ash detection by visual inspection and logging of sediment cores. Ash layer structure and texture, particle morphologies and lithological compositions of primary volcanic deposits are summarized and processes modifying them are discussed, both natural processes acting on and in the seafloor, i.e. erosion and bioturbation, and anthropogenic modifications during drilling/coring and core preparation. We discuss primary emplacement processes of marine fall and flow tephra deposits derived from either subaerial or submarine sources in order to identify distinguishing properties. We also elaborate on processes generating secondary, resedimented volcaniclastic layers such as submarine landslides and shelf erosion as well as fluvial input and ice-rafting, and how they can be distinguished from primary volcaniclastic deposits, which is essential in tephrostratigraphy. Finally, methods of tephra correlation between cores and on-land deposits/volcanoes are illustrated because they allow us to extend the 1D information from single cores to 3D distribution and facies changes of tephras and to bridge the land–sea gap.

Geological histories of volcanic ocean islands can be revealed by the sediments shed by them. Hence there is an interest in studying cores of volcaniclastic sediments that are particularly preserved in the many flat-floored basins lying close to the Azores islands. We analyse four gravity cores collected around the central group of the islands. Three sedimentary facies (F1-F2a, F2b) are recognized based on visual core logging, particle morphometric and geochemical analyses. F1 is clay-rich hemipelagite comprising homogeneous mud with mottled structures from bioturbation. F2a and F2b are both clay-poor volcaniclastic deposits, which are carbonate-rich and carbonate-poor, respectively. More biogenic carbonate in F2a reflects the incorporation of unconsolidated calcareous material from island shelves or bioturbation. Within F2a and F2b we identify deposits emplaced by pyroclastic fallout, primary or secondary turbidity currents by combining multiple information from lithological composition, sedimentary structures, chemical composition of volcanic glass shards and morphometric characteristics of volcanic particles. Primary volcaniclastic sediments were found in all four cores, echoing activity known to have occurred up to historical times on the adjacent islands. These preliminary results suggest that greater details of geological events could be inferred for other volcanic islands by adopting a similar approach to core analysis.

This paper presents the results of a laboratory experimentation carried out on stone materials in the framework of the CRATI project (Knowledge and Restoration through Advanced Integrated Technologies) aimed at testing new products with consolidating properties by means of an integrated methodological approach. After the preliminary characterization of stone materials collected in the pilot site, the second stage of the activities within the project were focused on the formulation and testing of products for the conservation of the same materials against decay, especially salt crystallization, one of the most aggressive and common degrading processes. The San Domenico Church, located in the old town of Cosenza (Calabria, Southern Italy) has been chosen as the pilot site and for the in situ tests. Several specimens with the same features of the stone materials used in San Domenico church were collected from a historical quarry near the city of Cosenza. These specimens were treated and then artificially degraded by salt crystallization tests in order to evaluate their susceptibility to weathering intensity. Three different consolidating products were used, respectively, two commercial and another one formulated in laboratory: (a) a suspension of nanosilica (Nano Estel&reg, ), (b) a suspension of nanolime (CaLoSiL&reg, ), and (c) a suspension of nano calcium-hydroxide dispersed in isopropyl alcohol and then mixed with diammonium hydrogen phosphate. A systematic approach, including minero-petrographic, geochemical and physico-mechanical techniques, was applied to evaluate (a) the nature and main features of materials, (b) the efficacy of consolidating treatments, and (c) the resistance of treated stone to the salt crystallization processes. The tested products demonstrated a significant efficiency to consolidate and protect stone material samples, enhancing their resistance to salt crystallization. Thus, such a case history may be useful in order to plan appropriate restoration interventions that consider the interactions between the building stone and the protective/consolidating product.

This study proposes an integrated methodology which includes pedological, petrographic, mineralogical and geochemical analyses of transparent heavy-minerals, to reconstruct the weathering patterns and pedogenetic processes in a transport-limited erosion regime. Three representative soil profiles developed on crystalline bedrocks, located in Calabria, southern Italy, were studied in detail including the complete weathering profile along the transect bedrock/grus/soil. Differences in the amounts of heavy minerals in each soil profile appear to be controlled by the nature of the local bedrocks. The addition of allochthonous parent material and a varying extent of chemical weathering, likely influenced by topography and duration of pedogenesis. The heavy mineral shapes and surface microtextures, together with the vertical distribution of major and trace elements, the values of the chemical index of alteration and the relative abundance of the clay mineral types along the profiles highlight the different weathering degrees among the profiles. These features are consistent with iron/manganese oxy-hydroxides and clay neogenesis observed on femic heavy minerals. Moreover, they mark a lithological discontinuity between the bedrock and the upper soil horizons, which led to rejuvenation by erosive and colluvial processes along the slopes and/or aeolian deposition of allochthonous material, presumably including a Late Pleistocene to Holocene pyroclastic input. Chemical weathering affecting the majority of heavy minerals is consistent with high rainfall rates, soil moisture availability and acidic pH conditions likely favored by organic acids, prone to chemical reactions and leaching processes. The clay coatings and iron/manganese segregations in the Bt horizons of all the profiles studied suggest that they developed in a warmer humid climate during the interglacial stages of the Pleistocene.