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The supergene zone of the Cap Garonne mineral deposit (Provence, France) hosts one of the most remarkable mineralogy in the world with no less than 150 minerals, 16 of which are type locality. Such mineral diversity offers a detailed view of mineral and geochemical changes during weathering processes. The stratabound epigenetic primary mineralization occurs within a few meters-thick fluvial conglomerates resting above the Permian–Triassic transition and is probably related to Late Triassic–Early Jurassic hydrothermal events. The Cu–As mineralization in the lower part of the conglomerates is locally overlapped by a thin Pb–Zn-rich layer in the northern mine. The results show that the weathered part is significantly enriched in Cu, Pb, As, Zn, Ag, Ba, Sb, and Bi. The evolution of the supergene fluid is traced in an Eh–pH diagram by the succession of sulfides I (tennantite, galena), sulfides II (covellite), arsenates (olivenite), sulfates and sulfo-arsenates (brochantite, anglesite), and carbonates (malachite, azurite, cerussite). The primary sulfide oxidation acidified the host conglomerate and enabled the crystallization of secondary sulfides and arsenates. Efficient and rapid neutralization by the calcite cement of the host conglomerate and chlorite in the matrix caused successive precipitation of arsenates, sulfates, and carbonates. The supergene processes could be related to major periods of weathering in Western Europe (Early Cretaceous–Late Oligocene/Early Miocene). Erosion-prone periods may have contributed to the stripping of the Pb–Zn-rich layer in the southern mine.

The eastern part of the Souss Basin (Morocco) contains several Mn deposits in the Tasdremt district. Three Mn orebodies occur within the Cenomanian-Turonian dolostones and the Senonian (Coniacian to Maastrichtian) detrital series, the main orebody being located at the boundary between them. The Mn ores consist of coronadite group minerals, mostly coronadite and hollandite, in a karstified dolostone. New field observations, petrographic analyses, and geochemical data define the Tasdremt deposits as a karst-hosted accumulation (11–60 wt.% Mn), particularly enriched in Ba (1.5–8.2 wt.%) and Pb (1.0–5.0 wt.%) with poor contaminations in Al, Fe, and P. This study shows that the ore-forming process is similar to that occurring in the Imini C3 level, located ~ 100 km to the north-east. Such similarities with the high-grade pyrolusite-bearing ore suggest that the Tasdremt deposit is a lateral equivalent of the Imini deposits. However, the scarcity of pyrolusite in Tasdremt results in lower Mn grades, the Tasdremt ores being considered an aborted/incomplete system in comparison with the Imini deposits. 40Ar/39Ar geochronology of K-bearing Mn oxides yields late Cretaceous ages, defining three phases at ~ 91.5 Ma, ~ 77.5–82 Ma, and ~ 65–67 Ma. Although the source of metals remains hypothetical, mineralizing fluids were carried by O2-free groundwater that mixed with O2-rich shallow meteoric waters at the Tasdremt depositional site. The dissolution of the host dolostones and the karst environment have provided suitable conditions for the precipitation of Mn oxides, causing the coeval increase of pH and Eh, respectively. The Early Atlasic deformation during the Late Cretaceous is associated with mineralization events and was responsible for creation of low stand reliefs from Tasdremt to Imini. This period enabled karstification and mineralization. Connecting the Tasdremt deposits to other African Mn deposits is difficult since the latter consist of laterite resting above Paleoproterozoic Mn protores, and consequently formed under different conditions from karst-hosted deposits. It is likely that other Mn occurrences formed along the Atlas belt in similar settings.

Feathers are amongst the most complex epidermal structures known and they have a well-documented evolutionary trajectory across non-avian dinosaurs and basal birds. Moreover, melanosome-like microbodies preserved in association with fossil plumage have been used to reconstruct original colour, behaviour and physiology. However, these putative ancient melanosomes might alternatively represent microorganismal residues, a conflicting interpretation compounded by a lack of unambiguous chemical data. We therefore used sensitive molecular imaging, supported by multiple independent analytical tests, to demonstrate that the filamentous epidermal appendages in a new specimen of the Jurassic paravian Anchiornis comprise remnant eumelanosomes and fibril-like microstructures, preserved as endogenous eumelanin and authigenic calcium phosphate. These results provide novel insights into the early evolution of feathers at the sub-cellular level and unequivocally determine that melanosomes can be preserved in fossil feathers.

Speleothems are secondary mineral structures typically found in karstic caves and usually composed of calcite or aragonite. Despite being naturally white, some might exhibit unusual colors, such as blue, black, red, yellow or green. The causes of these exceptional colorations are poorly understood, especially for green speleothems, which are barely reported. Here we describe the occurrence of the green Ni-bearing serpentine nepouite in green aragonite and calcite speleothems, in the Aven du Marcou (Hérault, France). Nepouite is mainly found as flat lamellar crystals in the outer rim of green speleothems and crystallized alongside radially grown aragonite crystals. This supports nepouite beginning to crystallize recently, due to a change in the chemical composition of the water. Nepouite also exhibits extensive substitution between Ni, Mg and Zn. The various elements responsible for nepouite precipitation are thought to come from the weathering of pyrite crystals in the overlying rocks, which is consistent with the pH conditions of the cave and the Al-free composition of nepouite. This study explains the crystallization mechanisms and stability conditions of silicate minerals in colored caves.

The Beni Snassen belt (northeastern Morocco) hosts several Mississippi Valley-type Pb-Zn ± Cu occurrences localized along the Variscan basement/Lower Liassic carbonate interface within the Atlasic foreland system. This study integrates geological observations with organic petrography and C-O-S-Pb isotopic systematics to constrain the origin of mineralizing fluids, metal source, and ore-forming processes within a basin-scale metallogenic system. The host sequence consists of unmetamorphosed, dolomitized Pliensbachian carbonates with marl interbeds and organic-rich black shales. Mineralization is structurally focused along ENE-WSW and E-W faults and occurs as massive calcite-galena veins, “en échelon” tension gashes, vug fillings, and solution-collapse breccias. Ore-stage calcite exhibits restricted isotopic variability (δ13C = −4.7 to +1.2‰; δ18O = 14.9 to 19.7‰), consistent with rock-buffered basinal fluids and extensive fluid–carbonate interaction. Calculated δ18OH2O values indicate precipitation from evolved saline brines variably mixed with meteoric waters. Galena δ34S values (−20.9‰ to +10.3‰) reflect thermochemical sulfate reduction (TSR) under fluctuating redox conditions. Pb isotope compositions define a tight linear cluster between upper crust and orogene growth curves, indicating a predominantly upper crustal metal source, notably Triassic dolerite–diabase lithologies, with a possible contribution from organic-rich black shales. High-reflectance pyrobitumen (VR0 up to 4%) indicates thermal conditions exceeding those predicted by local burial history, supporting long-distance migration of hydrocarbon-bearing metalliferous fluids from overpressured basin compartments, most plausibly the adjacent Neogene Guercif Basin. Fault reactivation during Late Miocene transtension fostered basin-scale fluid focusing and ore deposition. Hence, the Beni Snassen district represents a basin-integrated MVT system involving crustal metal leaching, organic-assisted metal transport, TSR-mediated sulfur reduction, and structurally focused fluid flow. These results refine metallogenic models for the Atlasic belts and highlight the exploration potential of structurally reactivated foreland basins hosting coupled hydrocarbon-hydrothermal systems.

The Velaux-La Bastide Neuve fossil-bearing site (Bouches-du-Rhône, France) has yielded a diverse vertebrate assemblage dominated by dinosaurs, including the titanosaur Atsinganosaurus velauciensis. We here provide a complete inventory of vertebrate fossils collected during two large-scale field campaigns. Numerous crocodilian teeth occur together with complete skulls. Pterosaur, hybodont shark and fish elements are also represented but uncommon. Magnetostratigraphic analyses associated with biostratigraphic data from dinosaur eggshell and charophytes suggest a Late Campanian age for the locality. Lithologic and taphonomic studies, associated with microfacies and palynofacies analyses, indicate a fluvial setting of moderate energy with broad floodplain. Palynomorphs are quite rare; only three taxa of pollen grains occur: a bisaccate taxon, a second form probably belonging to the Normapolles complex, and another tricolporate taxon. Despite the good state of preservation, these taxa are generally difficult to identify, since they are scarce and have a very minute size. Most of the vertebrate remains are well preserved and suggest transport of the carcasses over short distances before accumulation in channel and overbank facies, together with reworked Aptian grains of glauconite, followed by a rapid burial. The bones accumulated in three thin layers that differ by their depositional modes and their taphonomic histories. Numerous calcareous and iron oxides-rich paleosols developed on the floodplain, suggesting an alternating dry and humid climate in the region during the Late Campanian.

Unusual Ag-(Ni-Co-Sb-As-Hg ± Bi)-bearing fault-fill vein ore shoot mineralization set in a gangue of quartz, fluorite, and barite has been identified in Morocco’s Aouli deposit. The Paleozoic host rocks consist of a succession of Cambrian to Ordovician-aged folded and low- to medium-grade metasediments and metavolcaniclastic rocks with tuff interbeds and amphibolite sills, locally intruded by late Visean calc-alkaline to alkaline granitoid intrusions. Paragenetic relationships indicate that the sequence of ore precipitation comprises a succession of Ni-Co-Fe arsenides, followed by Pb-Sb-As-Ag-Hg sulfarsenides/sulfosalts and then Zn-Pb-Fe sulfides. Results indicate that the ore shoot mineralization formed from episodic stages of fracturing and subsequent fluid migration. Precipitation of ore phases is thought to have occurred as a result of isothermal mixing and subsequent fluid–rock interactions. The timing of mineralization is thought to have occurred between Late Triassic and Late Miocene, coinciding with major crustal extension and Middle Jurassic–Upper Cretaceous alkaline magmatism. Thermal convection and seismic pumping are proposed as the main driving force for the large-scale migration of the ore-forming brines. This research bears directly upon the potential for new exploration targets in Pb-Zn ± fluorite ± barite deposits hosted in Variscan inliers throughout North Africa.

The Paleocene-Eocene Thermal Maximum (PETM) is correlated with the first occurrences of earliest modern mammals in the Northern Hemisphere. The latest Paleocene Clarkforkian North American Land Mammal Age, that has yielded rodents and carnivorans, is the only exception to this rule. However, until now no pre-PETM localities have yielded modern mammals in Europe or Asia. We report the first Clarkforkian equivalent Land Mammal Age in the latest Paleocene deposits of the basal Sparnacian facies at Rivecourt, in the north-central part of the Paris Basin. The new terrestrial vertebrate and macroflora assemblages are analyzed through a multidisciplinary study including sedimentologic, stratigraphic, isotopic, and palynological aspects in order to reconstruct the paleoenvironment and to evaluate biochronologic and paleogeographic implications. The mammals are moderately diverse and not abundant, contrary to turtles and champsosaurs. The macroflora is exceptional in preservation and diversity with numerous angiosperms represented by flowers, fruits, seeds and wood preserved as lignite material, revealing an abundance of Arecaceae, Betulaceae, Icacinaceae, Menispermaceae, Vitaceae and probably Cornaceae. Results indicate a Late Paleocene age based on carbon isotope data, palynology and vertebrate occurrences such as the choristoderan Champsosaurus, the arctocyonid Arctocyon, and the plesiadapid Plesiadapis tricuspidens. However, several mammal species compare better with the earliest Eocene. Among these, the particular louisinid Teilhardimys musculus, also recorded from the latest Paleocene of the Spanish Pyrenees, suggests a younger age than the typical MP6 reference level. Nevertheless, the most important aspect of the Rivecourt fauna is the presence of dental remains of a rodent and a \"miacid\" carnivoran, attesting to the presence of two modern mammalian orders in the latest Paleocene of Europe. Interestingly, these two groups are also the only modern groups recorded from the latest Paleocene of North America, making Rivecourt the first direct equivalent to the Clarkforkian Land Mammal Age outside of North America.

The exhumation history of basement areas is poorly constrained because of large gaps in the sedimentary record. Indirect methods including low temperature thermochronology may be used to estimate exhumation but these require an inverse modeling procedure to interpret the data. Solutions from such modeling are not always satisfactory as they may be too broad or may conflict with independent geological data. This study shows that the input of geological constraints is necessary to obtain a valuable and refined exhumation history and to identify the presence of a former sedimentary cover presently completely eroded. Apatite fission-track (AFT) data have been acquired on the northern part of the Ardenne Massif close to the Variscan front and in the southern Brabant, in particular for the Visean ash-beds. Apatite fission-track ages for surface samples range between 140 ± 13 and 261 ± 33 Ma and confined tracks lengths are ranging between 12.6 ± 0.2 and 13.8 ± 0.2 µm. Thermal inversion has been realized assuming that (1) samples were close to the surface (20-40 °C) during Triassic times, this is supported by remnants of detrital Upper Permian-Triassic sediments preserved in the south of the Ardenne and in the east (border of the Roer Graben and Malmedy Graben), and (2) terrestrial conditions prevailed during the Early Cretaceous for the Ardenne Massif, as indicated by radiometric ages on paleoweathering products. Inversion of the AFT data characterizes higher temperatures than surface temperatures during most of the Jurassic. Temperature range is wide but is compatible with the deposition on the northern Ardenne of a significant sedimentary cover, which has been later eroded during the Late Jurassic and/or the Early Cretaceous. Despite the presence of small outliers of Late Cretaceous (Hautes Fagnes area), no evidence is recorded by the fission-track data for the deposition of a significant chalk cover as highlighted in different parts of western Europe. These results question the existence of the London-Brabant Massif as a permanent positive structure during the Mesozoic.

The early Eocene experienced a series of short-lived global warming events, known as hyperthermals, associated with negative carbon isotope excursions (CIE). The Paleocene-Eocene Thermal Maximum (PETM or ETM-1) and Eocene Thermal Maximum 2 (ETM-2) are the two main events of this Epoch, both marked by massive sea-floor carbonate dissolution. Their timing, amplitude and impacts are rather well documented, but CIEs with lower amplitudes also associated with carbonate dissolution are still poorly studied ( e.g. events E1 to H1), especially in the terrestrial realm where hiatus/disconformities and various sedimentary rates in a single succession may complicate the assignation to global isotopic events. Here we present a new high-resolution multi-proxy study on the terrestrial, lagoonal and shallow marine late Paleocene-early Eocene succession from two sites of the Cap d’Ailly area in the Dieppe-Hampshire Basin (Normandy, France). Carbon isotope data (δ 13 C) on bulk organic matter and higher-plant derived n -alkanes, and K-Ar ages on authigenic glauconite were determined to provide a stratigraphic framework. Palynofacies, distribution and hydrogen isotope values (δ 2 H) of higher-plant derived n -alkanes allowed us to unravel paleoenvironmental and paleoclimatic changes. In coastal sediments of the Cap d’Ailly area, δ 13 C values revealed two main negative CIEs, from base to top CIE1 and CIE2, and 3 less pronounced negative excursions older than the NP11 nannofossil biozone. While the CIE1 is clearly linked with the PETM initiation, the CIE2 could either correspond to 1) a second excursion within the PETM interval caused by strong local environmental changes or 2) a global carbon isotopic event that occurred between the PETM and ETM-2. Paleoenvironmental data indicated that both main CIEs were associated with dramatic changes such as eutrophication, algal and/or dinoflagellate blooms along with paleohydrological variations and an increase in seasonality. They revealed that the intervals immediately below these CIEs are also marked by environmental and climatic changes. Thus, this study shows either 1) a PETM marked by at least two distinct intervals of strong environmental and climatic changes or 2) at least one “minor” CIE: E1, E2, F or G, was associated with strong environmental and climatic changes similar to those that occurred during the PETM. L’Eocène inférieur fût le théâtre d’une série de réchauffements climatiques rapides et globaux nommés hyperthermaux qui sont associés à des excursions isotopiques négatives du carbone (CIE =  Carbon Isotope Excursion ). Le maximum thermique du Paléocène-Eocène (PETM =  Paleocene-Eocene Thermal Maximum ou ETM-1 =  Eocene Thermal Maximum -1) et le Maximum Thermique de l’Eocène-2 (ETM-2) sont les deux évènements principaux de cette Epoque et sont tous les deux marqués par la dissolution massive de carbonates des fonds marins. Leurs timings, amplitudes et impacts sont plutôt bien documentés, mais des CIEs de plus faible amplitude, également associées à des dissolutions de carbonates, sont encore peu étudiées (p. ex. évènements E1 à H1), notamment dans le domaine continental où les hiatus/inconformités ainsi que les taux de sédimentation variables dans une même succession compliquent l’identification des évènements isotopiques globaux. Ici, nous présentons une nouvelle étude « multi-proxy » à haute résolution sur la succession continentale, lagunaire et marine peu profonde de deux sites du secteur du Cap d’Ailly dans le Bassin de Dieppe-Hampshire (Normandie). Les données isotopiques du carbone (δ 13 C) de la matière organique totale et des n -alcanes de végétaux supérieurs ainsi que les âges K-Ar de glauconies authigènes ont été déterminés pour obtenir un cadre stratigraphique robuste. Les palynofaciès ainsi que la distribution et les données isotopiques de l’hydrogène (δ 2 H) de n -alcanes de végétaux supérieurs nous ont permis de reconstituer les changements paléoenvironnementaux et paléoclimatiques survenus durant l’intervalle étudié. Dans les sédiments côtiers du secteur du Cap d’Ailly, les courbes de δ 13 C montrent 2 principales CIEs négatives, de la base au sommet : CIE1 et CIE2, et 3 excursions négatives moins prononcées, toutes plus anciennes que la biozone à nannofossiles NP11. Alors que la CIE1 est clairement liée à l’initiation du PETM, la CIE2 pourrait correspondre, soit 1) à une seconde excursion au sein du PETM causée par un important changement environnemental local, soit 2) à un évènement isotopique du carbone global qui ce serait produit entre le PETM et l’ETM-2. Les données paléoenvironnementales indiquent que les deux principales CIEs sont associées à des changements importants comme l’eutrophisation, des proliférations d’algues et/ou de dinoflagellés associés à des variations paléohydrologiques et à une augmentation de la saisonnalité. Elles révèlent que les intervalles immédiatement sous les CIEs sont aussi marqués par des changements environnementaux et climatiques. Ainsi, cette étude montre que : soit 1) le PETM fut marqué par au moins deux intervalles distincts de forts changements environnementaux et climatiques, ou 2) qu’au moins une CIE mineure : E1, E2, F ou G fut associée à des changements environnementaux et climatiques similaires à ceux qui se sont produits pendant le PETM.