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Through the analyses of recovered pottery, this study explores the social dimension of an ancestor cult developed at the Petit-Chasseur megalithic necropolis (Upper Rhône Valley, Switzerland) during the Early Bronze Age (2200–1600 BC). The jar votive offerings and domestic pottery from settlement sites were characterized using a range of spectroscopic and microscopic techniques. Acquired archaeometric data allowed identification of six ceramic fabrics and two types of clay substrate—illite- and muscovite-based—which were used in pottery production. The present article discusses the pottery composition in the light of natural resources available in the region, thus shedding light on raw material choices and paste preparation recipes. The Early Bronze Age people that lived in the Upper Rhône Valley seem to have shared a common ceramic tradition, partly inherited from the previous Bell Beaker populations. The compositional correspondence between the jar offerings and domestic pottery revealed that the majority of the known Early Bronze Age groups partook in cultic activities at the Petit-Chasseur megalithic necropolis.

This work aims to unveil the origin, geodynamic significance, and diagenetic history of pyroclastites and associated chert documented within the Upper Anisian volcanosedimentary succession of the Ivanščica Mt. in Central Europe. An abundance of pyroclastic material points to polyphase volcanic activity and deep‐water sedimentation along the rim of an oceanic realm. Radiolarian‐based dating revealed Illyrian age of chert intercalated with pyroclastites. The latter are largely vitro‐crystalloclastic and were emplaced as airborne tuff. The crystalloclasts of sanidine, plagioclase, altered pyroxene, and amphibole are principal tuff constituents merged in the altered glassy matrix consisted of palagonite, clay minerals, and calcite. Variations in alteration assemblages reflect an extensive in situ eogenesis in an open hydrologic system that gradually evolved toward a restricted fluid percolation environment. Mineralogy, chemistry, and occurrence of andesitic tuff clearly denote an explosive volcanic activity formed at the top of suprasubduction zone. Such scenario presumes a complex genesis outlined in following steps: (a) partial melting and dehydration of down‐going Palaeotethyan slab which gave rise to the subduction‐related magmatism {; ; LILE, Th, and LREE [(La/Lu)cn = 6.51−9.42] enrichment ; negative anomalies of Nb‐Ta, P, and Ti [e.g., (Nb/La)n = 0.31−0.44]}; ; ; (b) magma contamination via interaction with continental crust during magma uplift along tectonically weakened zones of upper crust [positive Pb spikes, negative εNd (−4.18 to −4.44), and 147Sm/144Nd ≤ 0.113175]. This is in favour of geodynamic evolution that hypothesizes the existence of an active, ensialic, and mature volcanic arc developed along the southern active continental margins of Euramerica (Laurussia) during Late Anisian subduction of Palaeotethyan lithosphere.

The use of mineral diagenetic indices and organic matter maturity is useful for reconstructing the evolution of sedimentary basins and critical assessments for potential source rocks for petroleum exploration. In this study, the relationship of clay mineral diagenesis and organic matter thermal indices (Rock-Eval Tmax) and calculated vitrinite reflectance (%Ro) were used to constrain the maximum burial depths and temperatures of three distinct intervals within the northern Permian Basin, USA. X-ray diffraction of clay fractions (&lt, 2 &micro, m) consists of illite, chlorite, and illite-smectite intermediates. Primary clay mineral diagenetic changes progressively increase in ordering from R0 to R1 I-S between 2359.5 and 2485.9 m and the appearance of chlorite at 2338.7 m. Rock-Eval pyrolysis data show 0 to 14 wt% TOC, HI values of 40 to 520 mgHC/g TOC, and S2 values of 0 to 62 mg HC/g, with primarily type II kerogen with calculated %Ro within the early to peak oil maturation window. Evaluation of the potential for oil generation is relatively good throughout the Tonya 401 and JP Chilton wells. Organic maturation indices (Tmax, %Ro) and peak burial temperatures correlate well with clay mineral diagenesis (R0&ndash, R1 I-S), indicating that maximum burial depths and temperatures were between 2.5 and 4 km and &lt, 100 &deg, C and 140 &deg, C, respectively. Additionally, the use of clay mineral-derived temperatures provides insight into discrepancies between several calculated %Ro equations and thus should be further investigated for use in the Permian Basin. Accordingly, these findings show that clay mineral diagenesis, combined with other paleothermal proxies, can considerably improve the understanding of the complex burial history of the Permian Basin in the context of the evolution of the southern margin of Laurentia.

The verdine facies clay assemblages are regularly encountered in shallow marine sediments of equatorial latitudes where Fe of terrigenous origin is readily available. There, the 7 A Fe-rich green clay (odinite) of syn-sedimentary origin commonly occurs. Previous findings suggested that odinite serves as a precursor of diagenetic chlorite whose importance in porosity conservation has been widely acknowledged. The investigation of Fe-rich clays is, therefore, helpful to constrain the specific conditions and mechanisms, which give rise to chlorite growth, thus illuminating the history of early burial. In this contribution, we studied Cretaceous sediments from the Gabon coast where multiple sedimentary basins came into existence prior, during and after the opening of the South Atlantic. Analyzed core is siliciclastic and petroleum bearing stemming from the fluvio-lacustrine-deltaic environment recovered from depths of ∼1500 m TVD. Electron micro-beam investigation coupled with X-ray diffraction on the clay fraction and spectra fitting revealed odinite, interstratified odinite-chlorite (O-C), and to a lesser extent, illite-chlorite-smectite (I-C-S) and illite-smectite occur as grain coatings and pore-filling phases with a characteristic honeycomb texture. Embryonic chlorite emerges at the contact of odinite and O-C flakes as a particulate authigenic mineralization. Formed from aluminosilicate and Fe-oxyhydroxide debris at sediment-water interface, odinite becomes intrinsically unstable, possibly due to the activity of Fe-reducing bacteria or decaying organic matter creating a prevalently reducing environment that promotes Fe reduction. Such condition facilitated a two-step chlorite growth, which first included a partial chloritization of odinite through the in situ solid-state transformation of 7 A to 14 A layers. Then, with increasing burial, at peak diagenetic conditions (50 °C, ∼1.5 km depth), odinite and O-C both recrystallized to form eogenetic chlorite most likely following the Ostwald ripening mechanism.

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions of taxa in the genera Bunias, Calocedrus, Calycanthus, Celosia, Clerodendrum, Convolvulus, Crassula, Cyclamen, Datura, Dicliptera, Eragrostis, Erigeron, Gamochaeta, Gazania, Impatiens, Kolkwitzia, Leucaena, Ludwigia, Medicago, Muscari, Nigella, Oenothera, Opuntia, Paulownia, Petroselinum, Phyllostachys, Physalis, Pseudosasa, Quercus, Reynoutria, Roldana, Saccharum, Sedum, Semiarundinaria, Senecio, Sisyrinchium, Solanum, Sporobolus, Tulipa, Vachellia, Verbena, and Youngia. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1.

The Glasford structure in Illinois (USA) was recognized as a buried impact crater in the early 1960s but has never been reassessed in light of recent advances in planetary science. Here, we document shatter cones and previously unknown quartz microdeformation features that support an impact origin for the Glasford structure. We identify the 4 km wide structure as a complex buried impact crater and describe syn- and postimpact deposits from its annular trough. We have informally designated these deposits as the Kingston Mines unit (KM). The fossils and sedimentology of the KM indicate a marine depositional setting. The various intervals within the KM constitute a succession of breccia, carbonate, sandstone, and shale similar to marine sedimentary successions preserved in other craters. Graptolite specimens retrieved from the KM place the time of deposition at approximately 455 2 Ma (Late Ordovician, Sandbian). This age determination suggests a possible link between the Glasford impact and the Ordovician meteorite shower, an increase in the rate of terrestrial meteorite impacts attributed to the breakup of the L-chondrite parent body in the main asteroid belt

Paleozoic shale successions of Anadarko Basin in the central United States have historically been known as major hydrocarbon sources. Lately, their importance arises from the perspective of unconventional reservoir exploitation. Despite the better understanding of shale diagenesis and the agreement on many aspects of the transition of smectite to illite through a series of mixed-layer illite-smectite (I-S), the origin and composition of the material, and exact processes related to mechanisms of illitization remain controversial in shale. While nowadays most of researchers consider shales to be consisted of “illitic” clays, which comprises both the non-expandable 10Å layers as well as mixed I-S, some authors exclude the presence of smectite in mature shale attributing its appearance in XRD patterns by peculiar diffraction artefacts. The question of the nature of shaley matrix influences greatly rocks’ physicochemical parameters such as porosity/permeability and brittleness, which is essential for amelioration of the unconventional reservoir exploitation practices. In order to shed more light on crystal growth processes and clay mineral composition of shale matrix, an integrated study using different methodology was designed. Samples of Paleozoic shale of the Anadarko Basin were cored at depths from 2000 to 4200 m. Based on comparative mineralogical data - X-ray diffraction, electron microscopy and Infrared Attenuated Total Reflectance - and K-Ar age investigation performed on four illite fractions (2-1 μm

Miocene tuffs preserved in argillaceous sediment interbedded with lacustrine successions are commonly encountered throughout the Dinarides Lake System (DLS) in south-eastern Europe. In this contribution the volcanic glass degradation and co-genetic Mn-Fe precipitation were studied in a 14.68 Ma felsic tuff from DLS Livno-Tomislavgrad Basin. Microbial activity has been involved in both reactions thus adding the interest of revealing effects of biotic and abiotic processes taking place during tuff eogenesis. X-ray diffraction and electron microbeam analysis with energy-dispersive X-ray spectroscopy revealed the pitting or granular structures developed at glass rims along with smectite flakes protruding from a degrading glass. Mn-Fe mineralization emerges in the form of Mn-Fe coatings, an initial step to micronodule formation, where traces of biogenetic influence included a high content of phases rich in structural Mn (IV) (i.e., ranci&eacute, ite and jacobsite) and presence of microbial microfossils. Co-genetic ties between glass degradation and Mn-Fe precipitation were established through the report of dioctahedral smectite formed out of altered glass, which then served as nuclei of the ongoing biotic and abiotic Mn-Fe mineralization. These processes manifest on a continuous involvement of microbial life in the course of eogenesis of pyroclastic material in lacustrine environments.

In the southern U.S. states, expansive soils are frequently encountered, presenting an important hazard in geotechnical engineering. This research relies on mineralogical and geochemical clues to explain the swelling behavior of smectite-rich, high-plasticity soils, documented in a series of geomechanical swelling tests that were performed on the soils stabilized with the metakaolin (MKG) and fly ash (FAG) based geopolymers. These geopolymers were mixed with the soil at several concentration levels. The lowest swelling percentage was shown to correspond to the sample stabilized with 12% FAG and was attributed to the neoformation of calcium silicate hydrates that acted as a cementitious material, preventing the soil from expanding by occupying the pore space, thus binding the clay particles together. Conversely, the 12% MKG-stabilized soil exhibited enormous expansion, which was explained by montmorillonite swelling to the point that it gradually began to lose its structural periodicity. The relatively high abundance of the newly formed feldspathoids in MKG-treated samples is believed to have greatly contributed to the overall soil expansion. Finally, the cation exchange capacity tests showed that the percentage of Na+ and Ca2+, as well as the pH value, exercised strong control on the swelling behavior of smectitic soils.

Perialpine areas of central Europe have undergone significant changes following the last Alpine glaciation and especially through the Holocene time. This study relies on geochronological, mineralogical and geochemical clues to explain the formation and paleoenvironmental significance of Fe Mn nodules reported from the young soils (~4.5 ka BCE) of Geneva Basin in western Switzerland. Having on average 2 mm in diameter, the nodules usually possess an onion-like and quasi-layered internal architecture defined by selective enrichments in Fe and Mn. Fe-rich mica is largely present in soil matrix and has served as a main source of Fe and Mn. Susceptible to favourable Eh-pH conditions several steps in mica weathering were recognised leading to the formation of nodules – vermiculitization, microcracking, Fe Mn segregation and re-precipitation. Mineral alterations were boosted by long periods of summer warm climate during Boreal and Atlantic times as suggested by the increasing illite-smectite content and a disappearance of hydroxyl-interlayered clays from analysed colluvium. Moreover, archaeological ages and radiocarbon dating of charcoal yielded coherent Fe Mn encrustation ages (4.8–4.3 ka BCE and 4.5–4.4 ka BCE, respectively) that coincide with the Holocene temperature maximum (~4 ka BCE) in Central Europe. Terrain morphology that led to better water retention formed earlier than ~8 ka BCE ago, during undefined Late Glacial time, promoting seasonal changes in redox conditions, thus facilitating the mobilization, distribution and re-precipitation of Fe and Mn. Established conditions lasted until Late Neolithic (3.4–2.2 ka BCE) when different agricultural practices changed favourable hydromorphic environment effectively putting an end to further nodule formation.