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The herbivorous dinosaur clade Ceratopsia flourished in the northern hemisphere during the Late Jurassic to Late Cretaceous. Previous palaeobiogeographic studies have suggested that their initial diversification occurred in Asia, with early‐branching neoceratopsians extending their geographical range to North America sometime during the Barremian to Albian. However, the specific timing and mode of their dispersal from Asia to North America remains unknown. Here we describe a new, early‐branching neoceratopsian, Sasayamagnomus saegusai gen. et sp. nov., from the Albian Ohyamashimo Formation in southwestern Japan, representing the easternmost fossil record of ceratopsians in Asia. Sasayamagnomus exhibits three diagnostic features in the jugal, squamosal and coracoid, respectively, and also has a unique combination of characters in the lacrimal. Our phylogenetic analysis indicates that Sasayamagnomus forms a clade with Aquilops americanus, one of the earliest neoceratopsians from North America, followed by the sister taxon Auroraceratops rugosus from China. The present time‐calibrated phylogenetic tree indicates that the immigration of neoceratopsians from Asia to North America occurred during the latest Aptian or early Albian, refining the previously suggested timeframe. This aligns with fragmentary neoceratopsian fossil records from the Lower Cretaceous of North America and the initial formation of the Bering land bridge. Furthermore, the simultaneous occurrence of global warming (which enabled the development of extensive forests in the Arctic region) and the emergence of the Bering land bridge during the Aptian–Albian, probably played a crucial role in facilitating the immigration of neoceratopsians from Asia to North America. [ABSTRACT FROM AUTHOR]

Premise: The Aptian–Albian (121.4–100.5 Ma) was a greenhouse period with global temperatures estimated as 10–15°C warmer than pre‐industrial conditions, so it is surprising that the most reliable CO2 estimates from this time are <1400 ppm. This low CO2 during a warm period implies a very high Earth‐system sensitivity in the range of 6 to 9°C per CO2 doubling between the Aptian‐Albian and today. Methods: We applied a well‐vetted paleo‐CO2 proxy based on leaf gas‐exchange principles (Franks model) to two Pseudotorellia species from three stratigraphically similar samples at the Tevshiin Govi lignite mine in central Mongolia (~119.7–100.5 Ma). Results: Our median estimated CO2 concentration from the three respective samples was 2132, 2405, and 2770 ppm. The primary reason for the high estimated CO2 but with relatively large uncertainties is the very low stomatal density in both species, where small variations propagate to large changes in estimated CO2. Indeed, we found that at least 15 leaves are required before the aggregate estimated CO2 approaches that of the full data set. Conclusions: Our three CO2 estimates all exceeded 2000 ppm, translating to an Earth‐system sensitivity (~3–5°C/CO2 doubling) that is more in keeping with the current understanding of the long‐term climate system. Because of our large sample size, the directly measured inputs did not contribute much to the overall uncertainty in estimated CO2; instead, the inferred inputs were responsible for most of the overall uncertainty and thus should be scrutinized for their value choices. [ABSTRACT FROM AUTHOR]

The aculeate wasp family Sierolomorphidae is a small and enigmatic group including 14 species in 2 extant genera distributed in the Northern Hemisphere. Nothing is known about their biology, although ectoparasitoidism on insects has been speculated. Only 1 fossil genus from Turonian (Upper Cretaceous) amber was tentatively assigned to this family. The family Sierolomorphidae is recorded from the Early Cretaceous for the first time, representing the earliest occurrence of the family. Orisolemorpha dyscheres Álvarez-Parra and Engel gen. et sp. n. is described and figured from a male in upper Albian amber of San Just in Spain and is distinguished from all other genera in the family. The genus Loreisomorpha is here assigned to a new subfamily, Loreisomorphinae Álvarez-Parra and Engel subfam. n. based on its significant differences in wing venation relative to the remainder of the family. Taxonomic placement of the new genus is discussed, including a key for the fossil sierolomorphid genera. The ecology and biogeography of the family are reviewed. A checklist is provided of all living and fossil Sierolomorphidae. [ABSTRACT FROM AUTHOR]

Enicocephalomorpha, also known as uniqueheaded bugs, are a seldom-collected infraorder of heteropteran insects whose evolutionary relationships have puzzled entomologists for more than a century. Unique-headed bugs are exceptionally rare in the fossil record, which hinders our understanding of the morphological transformations of the lineage across time and also affects the calibration of molecular clock estimates used to date the origins of the infraorder. Here, we report the discovery of Enicocephalinus ibericus sp. nov. from Iberian amber in the Ari~no deposit in Spain, early Albian (Early Cretaceous) in age. The new species represents the second oldest fossil enicocephalomorphan to date, and the second record of this infraorder from European deposits. Remarkably, the closest relative of E. ibericus is the congeneric E. acragrimaldii Azar from Lebanese amber that is c. 20 myr older (Barremian), indicating a long-term persistence of the Enicocephalinus lineage across geological time. A review of the existing literature enabled us to record a total of 20 congeneric insect species that have been found in both Lebanese and Iberian ambers, suggesting the existence of previously underappreciated entomofaunal connections between southern Laurasia (the European archipelago) and northern Gondwana during the Cretaceous. We show that the palaeoentomological record holds remarkable potential for elucidating the faunistic exchanges and palaeobiogeographical patterns in the peri-Tethyan region during the Cretaceous. [ABSTRACT FROM AUTHOR]

The Lohan Cura Formation (Albian) at the Cerro de los Leones locality (Neuquén Province, Patagonia, Argentina) yielded several fossil materials, especially sauropod specimens. Among these, Agustinia ligabuei includes postcranial elements of a single individual, with widely debated taxonomy and phylogeny. Here, we provide an extended osteological description and illustrations of the axial and appendicular elements of Agustinia, as well as a revised diagnosis. Moreover, the phylogenetic analysis including a new combination of morphological features recognises Agustinia as a basal Rebbachisauridae, closely related with other South American rebbachisaurids. Our results suggest a more diversified sauropod fauna in the Neuquén Basin, where different members of both neosauropod lineages (i.e. Macronaria and Diplodocoidea) survived in the same region during the Albian age. The reassessment of Agustinia as a basal rebbachisaurid improves our knowledge about the early stages of evolutionary history of Rebbachisauridae, adding new information on the morphological and taxonomic diversification of the clade during the Early Cretaceous of southwestern Gondwana. [ABSTRACT FROM AUTHOR]

A new species of Nucleolites from the Lower Albian (Arcthoplites jachromensis Zone) of the Pavlovskoye section (Yuriev-Polsky District, Vladimir region) is described based on eight specimens. The species characterizes the late stages of the phylogeny of the genus and significantly expands its paleogeography. The taphonomic features of the burial made it possible to trace the structure of the lantern of the cassiduloid type in adult Nucleolites. For the first time in the Albian deposits of the Russian Plate, an extensive echinoderm assemblage, which is the most representative for the Lower Cretaceous deposits of the region as a whole, is revealed. [ABSTRACT FROM AUTHOR]

The cosmopolitan Late Albian ammonite subgenus Pervinquieria (Deiradoceras) van Hoepen, 1931, and its synonyms Cechenoceras van Hoepen, 1941 and Mimeloceras van Hoepen, 1944, originally based on material from northern KwaZulu-Natal, are reviewed. The type material of the type species, Subschloenbachia prerostrata Spath, 1921, is revised and reillustrated, as are its numerous synonyms. [ABSTRACT FROM AUTHOR]

The lower Upper Albian ammonite genus Dipoloceras Hyatt, 1900 (subfamily Mojsisovicsiinae Hyatt, 1903) is represented in KwaZulu-Natal by the type species, D. cristatum (Brongniart, 1822), marker species for the base of the Upper Albian Substage. Rhytidoceras van Hoepen, 1931 (of which Drepanoceras van Hoepen, 1931, non Stein 1878 and Ricnoceras van Hoepen, 1941, are synonyms), previously regarded as subgenera of Dipoloceras, are afforded generic status as are its supposed synonyms Diplasioceras van Hoepen, 1946a, and Euspectroceras van Hoepen, 1946a. The type species of these genera are revised, and assigned to the subfamily Pervinquierinae Spath, 1926. [ABSTRACT FROM AUTHOR]

The taxonomy of representatives of the genus Oscillopha Malchus, 1990 from the Aptian, Albian, and Cenomanian of the southwestern spurs of the Gissar Ridge (southeastern Turkmenistan) is revised. Issues of taxonomy of Mesozoic Lopha-like oysters are discussed. The diagnoses and composition of the family Arctostreidae Vialov, 1983, subfamily Arctostreinae Vialov, 1983, and genus Oscillopha Malchus, 1990 are specified. The genus Oscillopha is represented by the species O. eos (Coquand, 1869) in the Aptian and Albian and O. dichotoma (Bayle, 1849) in the Cenomanian. [ABSTRACT FROM AUTHOR]

We document diverse and well-preserved dinoflagellate cyst assemblages from Cretaceous successions in the Kullemölla 1 drill core (640.0 m–590.0 m), Vomb Trough, southern Sweden. Palynology reveals a nearshore marine environment. Dinoflagellate index taxa indicate an Albian to Coniacian age, thus spanning the Early–Late Cretaceous boundary. The lower part of the core is Albian, based on the presence of the index dinocyst taxa Pareodinia and Callaiosphaeridium asymmetricum. The First Appearance Datum (FAD) of Oligosphaeridium prolixispinosum, together with the presence of Achomosphaera ramulifera, Heterosphaeridium difficile and Oligosphaeridium pulcherrimum, reveals a Cenomanian age for the interval 635– m–617 m. The Turonian interval is characterized by an increase in the dinocysts Chatangiella spectabilis and Florentinia spp., in combination with the FAD of Senoniasphaera rotundata, whereas the youngest samples are dated to the Coniacian as defined by the appearance of Glaphyrocysta sp. We show that Cenomanian and Turonian strata are indeed represented by a relatively condensed section between 635 m and 612 m in the Kullemölla 1 core showing that the apparent hiatus recorded by calcareous microfossils elsewhere is likely a result of post-depositional dissolution of calcareous tests and limestone, a process that did not affect the organic-walled plankton. This is further supported by the presence of hardgrounds and dissolution features. This updated, detailed biostratigraphical assessment based on dinoflagellates provides a framework for correlation with zonations based on other marine fossil groups, useful, for e.g., correlating aquifers in subsurface successions and, further, provides opportunities for linking marine and continental biotas. [ABSTRACT FROM AUTHOR]

This research evaluates the potentials of argillite quarry waste (AQW) as raw material in ceramics and other industrial applications based on traditional firing techniques. In this context, the AQW samples were first characterized by mineralogical (X-ray diffraction, XRD), chemical (X-ray fluorescence) and physical (grain size distribution and Atterberg limits) analysis. From the results, AQWs composed predominately of clayey-silt with medium to high plasticity. The XRD revealed predominance of clay minerals (illite-chlorite-vermiculite) with high contents of quartz and variable percentages of carbonate and feldspar. The oxides were dominated by SiO2 and Al2O3, low contents of ferromagnesian elements with considerable amounts of alkali and alkali earth elements. The CaO concentrations are high and relate to carbonate contents. The feldspar contents and proportions of alkali and alkali earth elements revealed their potential as stating materials for earthenware production. Empirical assessments using compositional ternary and Winkler diagrams revealed their acceptable level in ceramic applications. To evaluate firing behaviors, the AQW samples were prepared and fired in the range of 800 to 1000°C and technological properties (linear shrinkage LS, weight loss WL, water absorption WA, bulk density and flexural strength FS) were determined. Statistical approach was employed with focus on accuracy and reliability of the data. At 800°C and above, results revealed an increase in LS, WL and FS with decrease in WA. The levels of performance of technological properties of the AQW are considered marginal except with SiO2 contents reduction by 5–10% and with the addition of degreasers. The AQW met the most requirements for grade I, II and III ceramic raw material and other industrial applications such as filler for paper, rubber, plastic and paint industries as described in Indian standard specification. To achieve excellent performance in ceramics and other industrial applications, AQW requires beneficiations. [ABSTRACT FROM AUTHOR]

Three species belonging to the fern genus Ochotopteris E. Lebedev, including the new species O. lebedevii Herman et Domogatskaya, are revised, described and illustrated in this paper. The fossils come from Albian, Cenomanian, Turonian and Coniacian beds exposed at seven sites in North-Eastern Asia and Northern Alaska. These sites are located in the Cretaceous Arctic, with their palaeolatitudes ranging from 60° N to 80° N. The high endemism characteristic of the mid-Cretaceous Arctic flora is most probably due to adaptations in the globally distinctive Arctic conditions: the unique combination of temperatures, precipitation and the highly seasonal polar light regime. Being an endemic plant of the mid-Cretaceous Arctic, Ochotopteris ferns were adapted to a regional wet temperate to a wet warm temperate palaeoclimate accompanied by marked sunlight seasonality with a prolonged—up to several weeks—winter darkness and continuous summer daylight, also lasting for several weeks. The majority of the mid-Cretaceous Arctic plants were deciduous. Their predominant deciduousness was most probably due to the polar light seasonality: at the end of the growing season, some plants dropped their leaves or leafy shoots, whereas others—including Ochotopteris ferns—died back to rhizome systems. [ABSTRACT FROM AUTHOR]

Beginning from the mid-Cretaceous and in the Late Cretaceous, the landscape features of the North Pacific make it possible to divide this region into a number of territories called subregions. The earliest Cenophytic (with a significant number and diversity of angiosperms) late Albian–early Turonian Grebenka flora and its analogs are known only in three subregions of the North Pacific: Anadyr–Koryak, Northern Alaska, and Yukon–Koyukuk. In the middle of the Cretaceous, these subregions represented coastal plains and lowlands periodically flooded by the sea. Cenophytic floras populated the area of terrestrial volcanism of the Okhotsk–Chukotka subregion and the Asian continental interiors of the Verkhoyansk–Chukotka subregion later, in the Turonian–Coniacian. However, Mesophytic vegetation with the predominance of Early Cretaceous ferns and gymnosperms continued to exist there at least until the Coniacian. Consequently, the invasion of evolutionarily new Cenophytic vegetation into the continental interiors of Northeast Asia was gradual and extended over time. This should be taken into account when studying the Cretaceous nonmarine phytostratigraphy of the North Pacific region. [ABSTRACT FROM AUTHOR]

The Nahr Umr Formation is considered one of the main reservoirs produced in southern Iraq. It is one of the important siliciclastic deposits of the Cretaceous sequence of Iraq oilfields. Zubair oil fields ZB-190 and ZB-047 were chosen to study areas. This study depends on the available core and cutting samples to determine the facies analysis, depositional environments, petrographic characteristics and diagenesis processes. Based on the description of the core and the borehole, six types of facies were distinguished in the Nahr Umr Formation, resulting in an intercalated sandstone and shale with a thin layer of siltstone. The petrographic study of the clastic part of the Nahr Umr Formation showed that the sandstone is composed mainly of quartz arenite. Diagenesis processes affecting the Nahr Umr Formation are two types compaction and cementation processes. The sedimentary environment of the Nahr Umr Formation was represented by the deltaic fluvial environments. These environments appear in the central and southwestern parts of the study area. Sequence stratigraphy in the Nahr Umr Formation is beginning by sequence boundary type one (SB1) and sequence boundary type two (SB2) that appeared in the upper part of the formation. The other surfaces were represented by the end of the deposition of the Nahr Umr Formation and the emergence of the transgressive ravinement surface (TRS) within the transgressive system tract (TST)and The maximum flooding surface (MFS) was distinguished in the middle of the formation and each of these surfaces has a lateral extension along the study section. [ABSTRACT FROM AUTHOR]

Despite the abundance of cockroaches (n = 593 specimens of 18 genera and 30 species) in the Mongolian Cretaceous, there is a single formally established and four reported species of Blattaria from the Shar-Tologoy (Valditermes acutipennis Ponomarenko, 1988; Liadoblattina mongolica Vršanský, 2003; Archimesoblatta altera Vršanský, 1997; Praeblattella dichotoma Vršanský, 2003; Cretophotina mongolica Gratshev and Zherikhin, 1993). Nuurcala coloris and Vitisma okata spp. n. are reported here from Early Cretaceous, which represent genera restricted to Laurasia. These fossil genera were documented from Early Cretaceous of Asia (Russian Baissa; Mongolian Bon Tsagaan, Sharin-Gol, Khulirt, Bakhar; Chinese Meitian, Yixian, Daohugou; Japanese Fukui) and Europe (Montsec, Spain). Samples with well-preserved venation and coloration provided correct systematic position with categorization of Shar-Tologoy to northern Laurasian biota (Baissa biota with all Cretaceous Mongolian sites) rather than to southern Jehol biota, and with transitional taxa. This evidences obscured long-lasting (> 50 Ma) isolated occurrences of certain abundant insect groups within narrow areas within Laurasia. [ABSTRACT FROM AUTHOR]

The Lower Cretaceous (Albian) clupeomorph fishes of the Pietraroja Plattenkalk were among the first fishes described for this celebrated Italian Konservat-Lagerstätte. However, a detailed anatomical and phylogenetic study has never been carried out on these fishes in order to clarify their taxonomic status, systematic position, and relationships within the Clupeomorpha. The specimens examined herein exhibit diagnostic features that clearly support their alignment with the extinct double-armoured herring order Ellimmichthyiformes. Based on the presence of an incomplete series of heart-shaped predorsal scutes, a new combination, Armigatus elatus (Costa, 1850), and the new species Armigatus plinii sp. nov. are recognized as the oldest representatives of the family Armigatidae, whereas a unique combination of features allows us to recognize most of the specimens as a new representative of the family Paraclupeidae, Paraclupea pietrarojae sp. nov. The presence of lower Albian species of Armigatus and Paraclupea in the Western Tethys extends the temporal and biogeographical range of these widely distributed genera, providing additional information for our understanding of the evolutionary and biogeographical history of the double-armoured herrings. [ABSTRACT FROM AUTHOR]

In this study, we describe a coral fauna from limestones of the Middle Albian, in the Espinazo del Diablo Formation, at a distance of 10km to the southeast of Tepache town, which is in the Lampazos area of Mexico. The corals did not form bioconstructions. A total of 46 species assigned to 22 genera that belong to the superfamilies Actinastraeoidea, Cladocoroidea, Cyclolitoidea, Eugyroidea, Heterocoenioidea, Misistelloidea, Stylinoidea, and Thamnasterioidea are reported. One genus and three species are described as new. The new genus Pentacoeniopsis belongs to the family Solenocoeniidae. The generic composition shows that the fauna is dominated by Early Cretaceous corals, and almost all species were indicated in the Early Aptian and Early Albian. Four genera have a range beyond the Santonian. Due to the relatively high number of endemic taxa, the coral fauna of the Lampazos area shows a low number of species that are shared with other studied areas, and coral fauna of the Bisbee Basin are the nearest with only 15 shared taxa. [ABSTRACT FROM AUTHOR]

The present study describes research carried out to evaluate the mineralogical, geochemical and technological properties of indurated shale-quarry wastes and assess the suitability of these low-cost and locally available quarry wastes generated from crushed indurated shales for possible use as alternatives to fresh raw materials in the manufacture of roofing-tile products. Firstly, the mineralogical and chemical properties of the indurated shales were investigated by X-ray diffraction (XRD) and X-ray fluorescence, while their physical properties were identified by grain-size distribution, Atterberg limits, and clay activity. Samples of indurated shale-quarry wastes (ISQWs) were subjected to heat treatment at elevated firing temperatures to provide the required strength and durability and their ceramics properties (linear shrinkage, weight loss, water absorption, bulk density, and flexural strength) were determined. From the results, the ISQWs were composed predominantly of fine particles with medium plasticity and clay activity with values generally >0.75. The mineralogy revealed a predominance of aluminosilicates (illite-kaolinite-smectite-chlorite) with large quartz contents and variable percentages of carbonate and feldspar. The oxides were dominated by SiO2 and Al2O3, small amounts of ferromagnesian minerals, and considerable amounts of alkalis (K2O and Na2O) which act as fluxes. The CaO concentrations were variable and related to carbonate contents. Characterizations based on compositional ternary (total clay mineral-carbonate-quartz + feldspar) systems, Casagrande clay workability charts, and Winkler and McNally diagrams revealed their suitability for ceramics applications as the majority of ISQW samples fell within the specifications for roofing tiles. The ISQWs fired at a high temperature of 1000°C revealed considerable weight loss, reduction in both linear shrinkage and water absorption with insignificant increase in flexural strength. In order to achieve excellent ceramics properties and further reduce sintering temperature for their suitability as raw materials in the production of roofing tiles, beneficiations of ISQWs are highly recommended. [ABSTRACT FROM AUTHOR]

The Northern Sahara Aquifer System (NSAS) is a complex system that includes several aquifers overlying most areas. The Continental Intercalary, also known as the "Albian groundwater" is an aquifer with impressive characteristics. It extends over three countries: Algeria, Tunisia and Libya. Intended for crop irrigation, the boreholes drilled in this Algerian aquifer, the boreholes carried out on this aquifer are artesian in their totality, with flows and pressures reaching in some places considerable values, of the order of 0,4 m3.s-1 for the flow and 3.106 Pa for the pressure. These two parameters are necessary to appreciate the energy potential of the Albian groundwater. A survey of the Continental Intercalary was carried out to study its energy potential. We were able to gather all possible data concerning the boreholes in the Algerian aquifer part. The study covered 295 boreholes that were identified and well documented, spread over 3 regions in southern Algeria. The water from the artesian boreholes in the Albian groundwater is transported to storage basins (for drinking water supply, irrigation and industry) for later use, or distributed directly to users after lowering the temperature of the water in the cooling towers. In these operations, all the hydraulic energy is lost and external energy is required from the electricity grid to meet the needs. The cumulative energy potential of all the boreholes identified has reached the theoretical value of 168GWh/year, the equivalent of 14520 toe (ton of oil equivalent) that are lost annually. Best management of this natural resource will not only enable resilient and sustainable management of the production systems and the environment, but also the energy needed to cool the water, as well as the energy needed for the maintenance of the boreholes and the facilities in the direct neighbourhood.

Because the Gulf Coast Lower Cretaceous is dated by ammonites, it has great potential as a reference section for correlating continental sequences such as the Potomac Group and dating events in the rise of angiosperms. Middle Albian terrestrial palynofloras from Oklahoma have been described in detail, but the early Albian interval, represented in the Glen Rose Formation of Texas, is less well known. Samples from two localities on the Paluxy River, which correlate with horizons containing late early Albian ammonites, are dominated by Classopollis and Exesipollenites, but angiosperm pollen is the next most common terrestrial element, and there are several index spore species for Zone II in the Potomac Group. Among the angiosperms, reticulate monosulcates are most common and diverse, but there are also several tricolpate species. Stratigraphically important angiosperms include the Clavatipollenites rotundus group and reticulate tricolpates, which appear in the upper part of Potomac Zone I and the dated earliest Albian of England and Portugal. However, there are also tricolpates with striate-reticulate sculpture, a pollen type that is not known from upper Zone I but appears in the late early Albian of Portugal. This assemblage contrasts with floras from Potomac Zone II and the middle Albian (lower Fredericksburg Group) of Oklahoma, where tricolpates overtook monosulcate angiosperms in species diversity. These results confirm arguments based on the Portuguese section that there is a significant hiatus between Potomac Zones I and II, and that this gap is at least partly late early Albian. The dominance of Classopollis and Exesipollenites and the occurrence of isolated Northern Gondwanan elements (Sergipea, Tucanopollis) suggest that Texas lay in a transition zone between Southern Laurasia and the hotter and drier Northern Gondwana province, but regional studies are needed to disentangle geographic and climatic factors from effects of the lagoonal local environment.

Late Albian -- early Cenomanian calcareous nannofossil assemblages from five mid-latitude localities (23-35°) were analyzed using probabilistic and deterministic methods to produce comprehensive and quantitative biostratigraphic sequences that were compared to the widely used 'CC' and 'UC' calcareous nannofossil zonation schemes. This was done to examine their fidelity and general applicability for mid-latitude biostratigraphy and determine whether these quantitative methods can increase the resolution of said schemes. Four biozones spanning the upper Albian through middle Cenomanian were determined using unitary associations (UAs) and ranking and scaling (RASC) optimumsequence from which last appearance datum (LAD) of -- Gartnerago stenostaurion, first appearance datum (FAD) -- Lithraphidites eccentricus, and LAD -- Staurolithites mutterlosei were determined to be reliable early Cenomanian markers at mid-latitudes, while the FAD and LAD of Calculites anfractus are unreliable bioevents and should not be used as a secondary marker for the Albian -- Cenomanian boundary. In addition, we have revised the stratigraphic position of the FAD of L. eccentricus, which was previously assigned to the middle-Cenomanian. The proposed FAD was shortly after the Albian -- Cenomanian boundary, before the FAD of Corollithion kennedyi. We conclude that UAs are more robust than RASC bioevents for this time sequence; however, both methods do not account for the asynchronicity of depositional and biotic chances. Despite these caveats, combining the results for both methods has proven to be a powerful quantitative biostratigraphic tool. [ABSTRACT FROM AUTHOR]

Representatives of the genera Ceratostreon Bayle, 1878, Pseudogyra Mirkamalov, 1971 and Costagyra Vialov, 1936 (Gryphaeidae, Exogyrinae) from the Aptian and Albian of the southwestern spurs of the Gissar Ridge are revised. In the Aptian and Albian, the genus Ceratostreon is represented by the species C. trigonalis (Mirkamalov), the genus Pseudogyra is represented by the species Pseudogyra pennata Mirkamalov, and the genus Costagyra is represented by the species C. luppovi (Mirkamalov). [ABSTRACT FROM AUTHOR]

Three species belonging to the fern genus Ochotopteris E. Lebedev, including the new species O. lebedevii Herman et Domogatskaya, are revised, described and illustrated in this paper. The fossils come from Albian, Cenomanian, Turonian and Coniacian beds exposed at seven sites in North-Eastern Asia and Northern Alaska. These sites are located in the Cretaceous Arctic, with their palaeolatitudes ranging from 60° N to 80° N. The high endemism characteristic of the mid-Cretaceous Arctic flora is most probably due to adaptations in the globally distinctive Arctic conditions: the unique combination of temperatures, precipitation and the highly seasonal polar light regime. Being an endemic plant of the mid-Cretaceous Arctic, Ochotopteris ferns were adapted to a regional wet temperate to a wet warm temperate palaeoclimate accompanied by marked sunlight seasonality with a prolonged—up to several weeks—winter darkness and continuous summer daylight, also lasting for several weeks. The majority of the mid-Cretaceous Arctic plants were deciduous. Their predominant deciduousness was most probably due to the polar light seasonality: at the end of the growing season, some plants dropped their leaves or leafy shoots, whereas others—including Ochotopteris ferns—died back to rhizome systems.

Premise: Reinvestigation of previously described fossil plants using improved techniques can provide insights for additional characters resulting in better family assignments and relationships to modern plants, as in this new study of the fossil fern Acrostichopteris from the mid‐Cretaceous. The discovery of new species within genera provides additional characteristics for comparisons and support for family assignments. Methods: Fossil material was uncovered from the matrix (degagement) for the specimens described here. Material was removed from the matrix and mounted for examination by scanning electron microscopy (SEM). Spores were extracted and prepared for examination with light, fluorescence, and SEM. Characters for the previously described material from the Potomac Group in the USA and the new material from Spain were compared with those of other fossils assigned to the genus. Results: The genus, described by Fontaine in 1889, reexamined by Berry in 1911, and assigned to the Schizaeaceae by Reed in 1947, is reassigned to the family Hymenophyllaceae on the basis of characteristics of the pinnules, sori, sporangia, and spores. We describe a new species in the genus from the Lower Cretaceous (Albian) of Spain that most likely belongs in this family, based on characteristics of the pinnules and the sori. A summary of all the species previously assigned to the genus is included. Conclusions: Assignment of this fossil to the family Hymenophyllaceae is based on all characters known and comparison to modern species, provides the time for appearance of characteristics within the family, and indicates diversification of Hymenophyllum species in the mid‐Cretaceous. [ABSTRACT FROM AUTHOR]

The Basque Coast UNESCO Global Geopark is known worldwide for its great thickness of Upper Cretaceous and Paleocene “flysch” formations. The K/Pg and P/E boundaries are among the most popular sites, together with the IUGS-ICS designated Selandian and Thanetian global stratotypes. However, an important section of the sea cliff outcrops is formed by an older and less known Albian “black flysch”. Its tectonic and sedimentological setting is related to the opening and spreading of the floor of the Bay of Biscay, which produced important environmental changes that triggered significant ammonoid bioevents, including the occurrence of large forms. Staff at the Basque Coast UNESCO Global Geopark (UGGp) and experts from the University of the Basque Country have carried out a research and geoconservation project based on a collection of more than 150 large-sized ammonites from a single fossil collector, who had accumulated them over 40 years from a particular location in the geopark cliffs. Integrative study of the sedimentary record and morphologies of the ammonoids collected through the section documents their distribution and evolution.

Fossil echinoids have rarely been described from Iran. This study focuses on the echinoid fauna found in the Cretaceous strata (Kazhdumi Formation) of the Geno and Gerash sections in the Bandar Abbas and Fars areas of the Zagros Mountains, southern Iran. The age of the Kazhdumi Formation in both sections is determined to be Albian-Cenomanian based on the associated ammonites and microfauna, its stratigraphic position, and previous studies on this formation. Twenty-one echinoid species (twelve regular and nine irregular) belonging to seventeen genera were described in this study. Fourteen of these species are reported for the first time from Iran. In addition, a new diadematoid echinoid species, Arabicodidema jafariani sp. nov. is introduced. New age ranges are proposed for Pliotoxaster comanchei and Lambertiaster douvillei. The paleogeographic position of the Zagros Basin in the Tethyan realm is confirmed based on the distribution of the index species. [ABSTRACT FROM AUTHOR]

Protosphyraena is one of the most widespread Cretaceous actinopterygian genera, with numerous species described primarily from the Upper Cretaceous of North America and Western Europe. However, most of the species are known from fragmentary and anatomically non-overlapping material, making the alpha taxonomy of this genus extremely problematic. Here we describe the first finds of Protosphyraena from the Albian of the Caucasus, and reassess the historical specimens from the Cenomanian of the Kursk Region of Russia. In an attempt to assign Russian specimens to a particular species, we review the global records and tangled taxonomy of Protosphyraena. The type species, P. ferox , is unambiguously known from teeth, cranial fragments and mandibles. The posteriorly directed rostral teeth of the type species cast doubt on the validity of Australopachycormus originally erected based on this feature. Our observations support the assignments of the historical Russian Cenomanian specimens to P. ferox and P. tenuirostris. We do not find sufficient cause to refer all isolated fins from Europe to P. ferox , as suggested by recent research. Instead, the species initially proposed by Agassiz for isolated fins from the English Chalk are available, and the fins of Protosphyraena from the Caucasus are consistent with one of these species, Protosphyraena gibberula comb. nov. Our findings indicate that Protosphyraena was widespread already in the late Early Cretaceous. Moreover, the youngest occurrence of Protosphyraena in Europe, a pectoral fin from the Maastrichtian of Belgium, demonstrates unique features and is thus referred to a new species, Protosphyraena terminalis sp. nov. • Protosphyraena was widespread already in the Albian. • Australopachycormus is a junior synonym of Protosphyraena • The youngest known Protosphyraena from Belgium represents a distinct new species. • Diversity of Protosphyraena pectoral fins in Europe reflected by 5 morphotypes. • Species level provincialism of Protosphyraena may be due to biased fossil record. [ABSTRACT FROM AUTHOR]

Abstract Carbonate deposits are numerous and have undeniable economic appeal for the oil industry. However, there are many uncertainties associated with different aspects of these lithologies. Understanding carbonate factories and their global distribution has been a subject of discussion in recent decades, especially concerning the products expected from different carbonate systems, their response to sea‐level variations and the transition between different depositional environments. Therefore, the goal of this study was to understand the role of sea‐level variations, and geodynamics in factories and the evolution of Albian depositional sequences on the south‐east continental margin of Brazil. Fifteen lithofacies consisting of seven facies associations and five third‐order sequences were identified. Sequence boundaries are unconformities formed by erosion or non‐deposition surfaces, representing either exposure periods or drowning events, and their correlative condensed sections. The first sequence, deposited in a shallow lagoon environment, recorded the onset of the T‐factory and the start‐up phase of the shelf. The second sequence represents a period of broad carbonate deposition in the basin, related to the catch‐up phase of the platform. The third sequence was established during a sea‐level rise and recorded the keep‐up phase of the platform and the transition from tropical to cool waters. The fourth sequence, was deposited in a deep marine environment and the fifth and last, recorded the shelf drowning. The succession typifies the beginning, the pinnacle and the end of carbonate deposition, spanning the initial and final highstand system tracts. The whole succession is part of a first‐order transgressive cycle that led to a factory transition and culminated with the definitive drowning of the depositional system.

Acanthohoplites aschiltaensis , a late Aptian ammonite originally described from the Caucasus of Dagestan, is recognised from the British Isles for the first time. A study of the full ontogenetic development of this species is enabled owing to the preservation of a mature body-chamber, not previously known. Stratigraphically, it confirms the correlation of the Fullers' Earth deposits within the Parahoplites nutfieldiensis Zone at Baulking, Oxfordshire, with strata of the Parahoplites melchioris Zone at the type locality and elsewhere. Palaeobiogeographically, it underlines the strong relationship between the Boreal fauna of western Europe and that of the Mediterranean-Caucasian Subrealm of the Tethyan realm. Additionally, a small Hypacanthoplites spp. fauna is described from the H. rubricosus Subzone of the Hypcanthoplites jacobi Zone at the Aptian/Albian boundary interval exposed in the Shanklin area, Isle of Wight. From this locality, otherwise almost devoid of ammonite remains, we present fairly well-preserved specimens of ' Hypacanthoplites' elegans , H. plesiotypicus , H. pricei , H. tenuiformis , H. rubricosus , H. sigmoidalis and H. sp. 1 indet., only known thanks to some decades of intensive collecting. In addition to the other members of this genus previously described from the British Isles, the occurrence of ' H.' elegans and H. plesiotypicus further supports the existence of narrow sea connections eastwards onto the European continent. [ABSTRACT FROM AUTHOR]

Geochemical study of Kazhdumi and Pabdeh Formations as potential source rocks in Gachsaran Oilfield demonstrates that the Kazhdumi Formation has a fair to good capability of hydrocarbon generation and predominately contains type II-III kerogen. On the other hand, the Pabdeh Formation has a poor to good petroleum potential and contains different kerogen types, including type II, type II-III, type III and even for one sample, type IV, indicating different depositional conditions for this formation. The geochemical log of the Kazhdumi Formation shows that there is a close correlation between different geological parameters as noticed prominently in well number 55, which suggests the more extensive the anoxic condition, the higher the petroleum potential is for Kazhdumi Formation. By contrast, a poor correlation between TOC and other Rock–Eval-derived parameters for the Pabdeh Formation at a depth of more than 2100 m may demonstrate the inert organic matter and mineral matrix effects at this depth interval. However, biomarkers show differences in lithology and depositional environment for the Kazhdumi Formation in well numbers 55 and 83. On the other hand, the Pabdeh Formation has a mixed lithology (carbonate-shale) deposited in a marine setting under suboxic–anoxic condition. Moreover, thermal maturity indicators suggest that Pabdeh and Kazhdumi Formations are immature and early mature, respectively. [ABSTRACT FROM AUTHOR]

Braconid parasitoid wasps are a widely diversified group today, while their fossil record from the Mesozoic is currently poorly known. Here, we describe Utrillabracon electropteron Álvarez-Parra & Engel, gen. et sp. nov., from the upper Albian (Lower Cretaceous) amber of San Just in the eastern Iberian Peninsula. The holotype specimen is incomplete, although the forewing and hind wing venation are well preserved. The new taxon is assigned to the subfamily †Protorhyssalinae (Braconidae) and, based on characteristics of the wing venation, seems to be closely related to Protorhyssalus goldmani Basibuyuk & Quicke, 1999 and Diorhyssalus allani (Brues, 1937), both from Upper Cretaceous ambers of North America. We discuss the taxonomy of the Cretaceous braconids, considering †Seneciobraconinae as a valid subfamily. We also comment on possible relationships within †Protorhyssalinae, although a phylogenetic analysis is necessary. Additionally, a checklist is included of braconids known from Cretaceous ambers. [ABSTRACT FROM AUTHOR]

Abstract Ammonite biostratigraphy could be used in age determination and correlation of rock units in different sedimentary basins. Qumenjan section with 125 meters thickness is mainly formed by grey sandy limestone with grey and thick-bedded limestone intercalations. The study area is located in the eastern margin of the Lut Block. For a stratigraphical study of Lower–Upper Cretaceous deposits in southwestern of Qayen area, a stratigraphic section was selected and measured. Eight ammonites, including Anisoceras, Calycoceras, Hypoturrilites, Hysteroceras, Mantelliceras, Puzosia, and Scaphites genera and thirteen representative species were identified. Based on the identified assemblage fossils and comparison with international biozones, Hysteroceras orbignyi subzone for Late Albian age, Mantelliceras mantelli biozone for the lower part of Early Cenomanian age, Mantelliceras dixoni biozone for the upper part of Early Cenomanian age, and Turrilites costatus biozone for Middle Cenomanian age is suggested. According to identified genera and species a Late Albian–Middle Cenomanian age is assigned for ammonite bearing of the section. The first occurrence of Mantelliceras mantelli is taken as the base of Cenomanian. Compression of the identified ammonites with other basins shows that the east Iran basin was a part of Tethys Realm during late Albian–middle Cenomanian. Keywords:Biostratigraphy, Ammonite, Albian, Cenomanian, Qayen, East Iran. Introduction Ammonites are one of the best macrofossils for Cretaceous biostratigraphy. The Albian and Cenomanian ammonites of Kopet Dagh and Central Iran have been studied by numerous researchers such as Seyed-Emami and Aryai (1981), Seyed-Emami (1977), Seyed-Emami, (1982), Seyed-Emami et al. (1984), Immel and Seyed-Emami (1985), Seyed-Emami and Immel (1995, 1996), Immel et al. (1997), Mosavinia et al. (2007), Mosavinia and Wilmsen (2011), Mosavinia et al. (2014), and Wilmsen et al. (2015). The Cretaceous deposits have spread in the east of Iran and in Birjand and Qayen area. These deposits have different facies. The Cretaceous rocks include conglomerate and sandstone units in the base and then changed to limestones in Late Barremain to Aptian. During Albian–Cenomanian, the depth of the sedimentary basin increased and thin-bedded limestones, marly limestones, and marls were deposited. The Lower Cretaceous succession is composed of different rock units that are outcropped in the eastern margin of Lut Block. These deposits usually start with a basal conglomerate. “Orbitolinind Limestone” is an informal name that is used for a succession containing Orbitolina limestone and marl intercalations. Aptian–Cenomanian succession mostly is composed of detrital, marl, and carbonate beds most of which are biogenic sediments deposited in carbonate platforms. Upper Cretaceous deposits are mostly widespread in Maastrichtian (Stocklin et al. 1972; Fauvelet and Eftekharnezhad 1990). Flyschiod facies are also spread with Ophiolites in Upper Cretaceous (Aghanabati2004). One of the oldest studies conducted in the east of Iran is published by Clap (1940). Several geological and paleontological studies have been done by several researchers such as Stocklin et al. (1972), Tirrul et al. (1983), Fauvelet and Eftekharnezhad (1990), Berthiaux et al. (1991), Raisossadat and Skelton (2005), Babazadeh et al. (2010), Khazaei et al. (2011), Raisossadat et al. (2016), Sharifi et al. (2016), Motamedalshariati et al. (2016), Raisossadat and Noori (2016), Latifi et al. (2018), Raisossadat et al. (2017) and Zarei et al. (2019). Despite the above-mentioned studies , there still seems the need to do more studies in paleontological fields. Ammonites are known as useful fossil groups in age determination and are used as biostratigraphical and biozonation tool for the Cretaceous deposits. The aim of this study is to provide an ammonite biozonation and a short palaeobiogeographic discussion on the Cretaceous deposits of the study area. Material & Methods Based on the geological map and field observation, a stratigraphical section was selected and measured in the southwest of Qayen and in south of the Qumenjan Village. The geographical coordinates of the base of the section are 58° 52' 11" E 33° 32' 19" N. Sixteen rock and ammonite samples were collected. Ammonites were cleaned, covered with magnesium vapor and photographed. Collected specimens were identified. The collected samples were stored in the Department of Geology, University of Birjand. Discussion of Results & Conclusion The Qumenjan section with 125 meters thickness starts with a conglomerated bed at the base, and then continues with sandy limestones. The major part including a succession of grey limestone and argillaceous limestone intercalations. In this study, the following ammonites are identified: Anisoceras plicatile, Calycoceras gentoni, Calycoceras (Newboldiceras) asiaticum, Calycoceras sp., Hypoturrilites sp < em>., Hysteroceras orbignyi, Mantelliceras dixoni, Mantelliceras saxbii, Mantelliceras mantelli, Mantelliceras cf. lymense, Puzosia (P.) sp., Scaphites sp. Based on reported microfauna (Ahrari 2009; Moloudi 2014) and identified ammonites a Late Aptian to Middle Cenomanian age is suggested for the section. Based on the identified ammonites, the following biozones is suggested for the studied section: Hysteroceras orbignyi subzone: this subzone is introduced as an index subzone for the Late Albian. Range of this zone is from the first occurrence of Hysteroceras orbignyi to the first occurrence of Mantelliceras mantelli. The associate ammonite is Puzosia sp. The thickness of this subzone is 25 meters. Mantelliceras mantelli Interval Zone: This zone is reported from south of the UK, France, Spain, and Portugal and south of Africa. Mantelliceras mantelli is discussed as index zone of Early Cenomanian. The range of this zone is from the first occurrence of Mantelliceras mantelli to the first occurrence of Mantelliceras dixoni. The associate ammonites are Hyphoplites cf. costosus, Hypoturrilites cf. gravesianus, Scaphites sp. The thickness of this subzone is 19 meters. Mantelliceras dixoni Interval Zone: This zone is an index zone for lower part of Middle Cenomanian. However, this zone could confirm Middle Cenomanian. The range of this zone is from the first occurrence of Mantelliceras dixoni to the first occurrence of Turrilites costatus. The associate ammonite is Mantelliceras cf. lymense. The thickness of this subzone is 14 meters. Turrilites costatus Interval Zone: This zone is introduced by Hancock (1991). Alabushev (1995) introduced it as a subzone. Wilmsen et al. (2007) mentioned Anisoceras plicatile and Turrilites costatus as index fossils for Acanthoceras rhotomagense Zone. Kennedy and Gale (2015) reported Calycoceras gentoni from Middle Cenomanian. Acanthoceras rhotomagense is reported as the index zone of Middle Cenomanian. In the studied section A. rhotomagense has not been reported. Therefore, based on the occurrence of Turrilites aff. costatus Zone, Middle Cenomanian age is suggested for the upper part of the section. The associate assemblages include Calycoceras (Newboldiceras) asiaticum, Calycoceras gentoni, Anisoceras plicatile and Calycoceras sp. Latitudinal and provincial control of ammonite faunas was common throughout the Mesozoic. Both the ranks (realm, province, etc.) and names have varied from author to author. Tectonic movements and sea-level changes (regressions and transgressions) caused seaways connecting basins to open marine or close and led to several distinct new basins or limitation of seaways and between marine basins. Thus, numerous sub-realms and provinces have been named. Three biogeographic realms existed during the Mesozoic; Boreal Realm embraced the Arctic basins and the seas extending southward from there over parts of North America, Northern Europe, and Siberia. The Boreal seas were largely landlocked but linked by narrow seaways to the Tethyan Realm. The Tethyan Realm includes low latitude areas such as Africa, the Pacific, the Middle East, and America, and centered on the Paleo-Tethys Ocean. An Austral Realm has also been proposed for high southerly latitudes (Stevens 1973). To study the palaeobiogeographic conditions of Upper Albian–Lower Cenomanian in eastern Iran, the ammonite fauna of the studied section was compared with other reported ammonites from different areas. The reported ammonites from east of Iran show affinity with those reported from Kopet Dagh, Central Iran, Europe, and USA. The absence of Scholenbachia that is an index genus of the Boreal Realm and the presence of some genera such as Anisoceras, Scaphites, Hypoturrilites, and Puzosia could suggest that the study area is a part of Tethys Realm. However, the presence of Mantelliceras could show the effects of the influence of Boreal. The analysis of the ammonite stratigraphic distribution in the selected section in east of Iran allowed us to establish the faunal succession for the Upper Albian–Middle Cenomanian in the region. Based on identified assemblage, the following biozones are suggested. Hysetroceras orbignyi subzone is suggested as index zone of Late Albian, Mantelliceras mantelli Zone could confirm lower part of Early Cenomanian, Mantelliceras dixoni Zone is known as the upper part of Early Cenomanian and Turrilites costatus Zone is suggested as Middle Cenomanian. Compression of the identified ammonites with other basins shows that the east Iran basin was a part of Tethys Realm during Late Albian–Middle Cenomanian.

Rich and well preserved organic-walled dinoflagellate cyst assemblages recovered from the Scisti a Fucoidi Formation at Piobbico, central Italy are presented. Distributions of 83 taxa, plotted against the independent stratigraphic framework established from planktonic foraminifers and nannofossils, are compared with ranges documented in the literature in order to identify and calibrate reference horizons for the Albian dinoflagellate cyst stratigraphy of the Tethyan Realm. The following events have been selected: the lowest occurrences of Kleithriasphaeridium atlasiense and Tehamadinium coummia at the Aptian/Albian boundary, of Leberidocysta defloccata in the Lower Albian, of Adnatosphaeridium tutulosum, Litosphaeridium arundum and Ovoidinium sp. A sensu Davey (1979) in the Middle Albian, of Dapsilidinium? pumilum, Litosphaeridium conispinum, Tehamadinium mazaganense and Hapsocysta dictyota in the Upper Albian; the highest consistent occurrences of Hapsocysta peridictya in the Lower Albian, of Codoniella psygma and Damassadinium chibane in the Middle Albian, of Tehamadinium sousense in the Upper Albian.

The Lower Cretaceous Blackleaf Formation in southwestern Montana records sedimentation in the Idaho‐Montana retroforeland basin of the North American Cordillera. Regional‐scale sedimentology suggests that during Albian time southwestern Montana was partially flooded by an early marine incursion of the Western Interior Seaway during deposition of the Blackleaf Formation. We use sandstone petrography, large‐n (n = 600) U‐Pb detrital zircon geochronology and mixture modelling to determine the provenance of these strata. Our analysis suggests three distinct provenance groups: Group 1 sandstones occur in the eastern region of the study area, are quartz‐rich and have zircon age‐probability peaks of ca. 110, 160, 420–450, 1050 and 1160 Ma; these sandstones match with a primarily Appalachian provenance. Group 2 sandstones occur in the western region of study area, are lithic‐rich and have peaks of ca. 110, 160, 1780, 1840, 1920, 2080 and 2700 Ma; the primary source for these sandstones was exhumed lower‐middle Palaeozoic strata from the Idaho sector of the Sevier belt. Group 3 sandstones occur in the western region of the study area, are lithic‐rich and have prominent peaks of ca. 115, 170, 430, 600, 1085, 1170, 1670 and 1790 Ma; the primary source for these sandstones was exhumed Triassic‐upper Palaeozoic strata from the Idaho sector of the Sevier belt. Our provenance data record a sharp change that coincides with the western shoreline of the seaway, and we infer that it may indicate the position of an irregular, submarine forebulge depozone influenced by dynamic subsidence during a period of reduced thrusting in the adjacent fold‐thrust belt. Albian‐aged sediments in southwestern Montana were delivered by rivers with headwaters in the Sevier belt as well as transcontinental river systems with headwaters in eastern North America. In southwestern Montana, west‐flowing transcontinental fluvial systems were flooded by the Western Interior Seaway as it encroached from the north. [ABSTRACT FROM AUTHOR]

To investigate biostratigraphy of Albian sediments (Kazhdumi Formation) in the Zagros Basin, 280 samples in four sections were prepared which are nominated as Murshan-e-Bala, Fahliyan-e-Pain, Kupon and Tale-e-Afghani. Stratigraphic distribution of identified foraminifers confirms well developed orbitolinids which are associated with other Albian benthic foraminifers in all studied sections. The orbitolinids are recognized in surrounding strata [Dariyan (at the base which is marked by an oxidized zone) and Sarvak Formations (on the top, as gradtional contact)] as well as the Kazhdumi Formation. Obtained biostratigraphic data show that Early Albian is marked by the presence of Hemicyclammina sigali, which co-occurs with Mesorbitolina texana and Mesorbitolina subconcava, whereas Conicorbitolina conica and Meorbitolina parva support Late Albian age of the studied sections. Calcareous algae are associated with both benthic faunal assemblages. Albian planktons occur in the studied sections which are identified as Favusella washitensis and Calcisphaerula inomminata subzones. The stratigraphic position of planktons actually indicates vertical displacement in the sedimentary basin during Albian time. Other associated Albian pelagic foraminifera are identified which are obviously recognized in three sections of the Kazhdumi Formation. The presence of pelagic species in the study section of the Kazhdumi Formation indicates basement faulting during the Albian period. [ABSTRACT FROM AUTHOR]

Pedogenic carbonate samples collected from three Lower Cretaceous (Aptian–Albian) fossil localities in Texas and Oklahoma were analyzed to develop paleoatmospheric pCO2 estimates by measuring the stable carbon isotopes of pedogenic calcite and their co-existing occluded organic matter. Calcite δ13C values ranged from −10.9‰ to −4.4‰ while occluded organic matter δ13C values ranged from −27.3‰ to −21.1‰. These stable carbon isotope measurements combined with temperature (30 °C) and soil-respired CO2 concentration (839–6047 ppmV) values provided atmospheric pCO2 estimates ranging from 67 ppmV to over 1100 ppmV. These estimates show a significant increase in atmospheric pCO2 during the late Aptian followed by a decrease in atmospheric pCO2 during the late Aptian to early Albian transition period, roughly correlating with the OEA1b event. Given the lack of chronostratigraphic constraints of the Lower Cretaceous geologic units in the study area, these data provide further evidence for the approximate age of the units as well as pertinent paleoclimate insights into greenhouse climate conditions. [ABSTRACT FROM AUTHOR]

This sedimentological and palaeontological analysis of the Aptian–Albian sedimentary succession of the Ait Ourir basin in the High Atlas Mountains of Marrakesh in Morocco provides new data from a previously poorly understood basin. The palaeoenvironmental evolution is deduced based on a facies analysis allowing the restoring of depositional environments and their stratigraphic architecture. Within the Aptian–Albian succession, we distinguish two sedimentary sequences separated by a major discontinuity. The first sequence is composed of calcareous and dolomitic marls with the rudist Pseudotoucasia catalaunica of the Tadhart formation (upper Aptian in age) and of strongly dolomitized limestones with corals (Eugyra sp., Thalamocaeniopsis sp., and Holocystis sp.) of the Lemgo formation (uppermost Aptian in age). These two formations were formed in an internal carbonate platform (the intertidal zone to the subtidal zone). The second sequence, Albian in age, is composed of sandy limestones of the Oued Tidzi formation and is represented by sediments showing terrigenous influence, with deposits of silt, sandstone, dolomitic sandstone, and limestone.

To evaluate the quality and durability of crushed aggregates for certain engineering applications, better knowledge of their mineralogical and chemical characteristics and physico-mechanical properties become very imperative. In this present study, using X-ray diffraction technique along with chemical analysis, representative samples of argillite were tested for mineral compositions, and basic geotechnical tests were used to evaluate their physical and mechanical properties to ascertain their suitability as road aggregates. The results from evaluated properties were compared with the acceptable criteria in national and international usage. Statistical relationships existing between the physical and mechanical properties were described using simple regression analysis. From the results, the mineralogy and chemical characteristics revealed the predominance of quartz, illite, and feldspar reflected in the relatively high silica, aluminum, and alkali contents in the average chemical analysis. The low absorption capacity and high specific gravity influenced positively the mechanical strength. The aggregate crushing, aggregate impact, and Los Angeles abrasion values were generally lower than the maximum allowable value of 30%, an indication that the aggregates, in addition to having sufficient strength to withstand high stresses, have high resistance to impact and abrasion. The high 10% fines values of over 150 kN indicate strong and durable road materials suitable for many special engineering uses. The argillite indicates good road material that can offer significant economic and environmental benefits but would require informed caution. The argillite aggregate high strength and attrition resistance with its cheaper abundance will continue to be prominent factors in its utilization for road projects. [ABSTRACT FROM AUTHOR]

The representatives of the genus Amphidonte Fischer de Waldheim, 1829 from the Aptian and Albian of the southwestern spurs of the Gissar Ridge are revised. In the Aptian, this genus is represented by a new species A. mirkamalovi sp. nov., in the Albian—by the species A. zachanensis Mirkamalov, 1966. [ABSTRACT FROM AUTHOR]

Chineiveem taphoflora from the Krivorechenskaya Formation of the Anadyr River left bank (Northeast Asia) is characterized by a relatively low diversity of plants represented by ginkgoaleans, conifers, and angiosperms. Judging by their systematic composition, this taphoflora is younger than the Grebenka flora from the Krivorechenskaya Formation of the Anadyr River basin. Its closest analog is the Penzhina flora of Northwestern Kamchatka and the Yelistratov Peninsula, the age of which is reliably defined as Turonian, excluding the beginning of the Turonian. Therefore, the age of the Chineiveem floristic assemblage is also Turonian, most probably late Turonian. Such dating of this taphoflora is in agreement with the late Turonian or Coniacian age of marine mollusks from the overlying Dugovskaya Formation layers of the Chineiveem River and with a conformable stratigraphic contact of these layers with the plant-bearing beds. A tectonic contact between these deposits is not supported by our paleobotanical data. The observed succession of taphofloras from the Krivorechenskaya Formation in the Ubiyenka–Chineiveem interfluve suggests that the upper age limit of the Grebenka flora is the beginning of the Turonian. [ABSTRACT FROM AUTHOR]

A total of 64 samples were collected from the Kazhdumi Formation (Albian) of south Zagros Basin (Coastal Fars Zone) in order to study the biostratigraphy and analyse the lithofacies. Stratigraphic distribution of identified larger benthic and planktonic foraminifers has confirmed the presence of three successive biozones: Mesorbitolina subconcava‐Orbitolina discoidea Zone, Favusella washitensis Zone followed by an upper Conicorbitolina conica‐Mesorbitolina parva Zone. Generally, orbitolinids are well developed in the Albian succession in the studied section, whereas the stratigraphic distribution of planktonic foraminifers is more restricted, dominating the Favusella washitensis Zone. Nevertheless, microscopic investigation recognizes five microfacies consisting of extraclast‐foraminifer packstone, peloid‐intraclast Orbitolina wackestone, foraminiferal plankton wackestone, intraclast‐Orbitolina grainstone, and coral‐rudist wackestone, which indicated a shallow water carbonates palaeoenvironment (intertidal, lagoon, bar) and open marine. The alternation of both planktic and benthic foraminifera through the Kazhdumi Formation confirms a rapid transgression and regression in the studied section during Albian time, which is attributed to Kazerun basement fault behaviour in the mentioned time interval. [ABSTRACT FROM AUTHOR]

Newly discovered dinosaur footprints from the Lower Cretaceous (Albian) Folkestone Formation (Lower Greensand Group) of Kent in S.E. England can be referred to theropod, ornithopod and possibly ankylosaur dinosaurs. The occurrence of dinosaur footprints, together with fossil wood and oysters in a matrix of well-rounded quartz grains indicates a coastal depositional environment of an extremely shallow depth, perhaps with short periods of subaerial exposure. This is the first record of dinosaur footprints from the Folkestone Formation, and it represents the youngest association of dinosaur footprints from England. The moderately diverse dinosaur ichnoassemblage of theropods, ornithopods, ankylosaurs and previously documented fossils indicate deposition on a sandy beach setting. [ABSTRACT FROM AUTHOR]

We wish to point out an obvious error made by one of us (J.F. Deconinck), and kindly reported by J.G. Bréhéret, the reason why we have jointly decided to publish this correction. The error affects at varying degrees the scientific quality and partly invalidates the conclusions of the following articles: Corentin et al. (2020) « Environmental and climatic controls of the clay mineralogy of Albian deposits in the Paris and Vocontian basins (France) » (Cretaceous Research, 108). and Ait-Itto et al. (2023) « Astronomical calibration of the OAE1b from the Col de Pré-Guittard section (Aptian–Albian) Vocontian Basin » (Cretaceous Research, 150). Indeed, for the Vocontian basin, the analytical work, whatever its quality, was carried out on a stratigraphic interval which does not correspond to the presentation made. The two articles in question did not take into account the detailed lithostratigraphy and biostratigraphy earlier published, notably by Bréhéret (1997) and Bréhéret & Brumsack (2000) mentioning known marker beds as presented in these works. Thus, for one of the two sections, the displayed time window assumed to be the lower Albian, actually corresponds to a small part of the middle Albian and a part of the upper Albian. This invalidates many of the proposed results and conclusions. [ABSTRACT FROM AUTHOR]

Studies on the involvement of intrusive magmatism in hydrocarbon generation within sedimentary basins have gained momentum owing to increasing appraisal of the role that such processes may play in controlling global carbon cycle perturbations, and the exploration potential of the volcanic sedimentary basins. Nevertheless, for many areas the causal link between the intrusions and surrounding hydrocarbon systems remains disputed, encouraging a search for methods that could aid in identifying different hydrocarbon sources. Here, we have performed a multi-proxy geochemical study of the middle Cretaceous methane-seep deposits of the Basque-Cantabrian Basin, an early-stage, peri-cratonic rift marking the Mesozoic opening of the Bay of Biscay. Infilled by a thick sedimentary succession intruded by shallow-level igneous bodies, the basin shares analogies with modern young, sedimented rifts that sustain hydrocarbon seepage. We have applied a novel approach that uses the Nd isotope composition of the seep deposits to constrain the relationship between hydrocarbon seepage and igneous activity, and to explore the general potential of Nd isotopes to trace magmatic-influenced fluids in volcanic sedimentary basins. The Nd isotope data have been combined with rare earth element analyses and carbon and oxygen isotope measurements, providing broad insight into the former composition of the seeping fluids. For three out of four investigated seeps, the Nd isotope ratios observed in authigenic seep carbonates include signatures markedly more radiogenic than that reconstructed for background seawater-derived pore waters. The level of this 143Nd-enrichment varies both between and within individual deposits, reflecting spatial and temporal differences in fluid composition typical of seep-related environments. The radiogenic Nd isotope signals provide evidence of subseafloor interactions between the seeping fluids and mafic igneous materials, supporting the model of an igneous control on the mid-Cretaceous methane expulsion in the Basque-Cantabrian Basin. The thermogenic origin of the methane is in accord with the moderately negative δ13C values and paragenetic successions observed in the studied seep carbonates. For a single deposit, its relatively unradiogenic Nd isotope composition can be attributed to the smallest size and shallowest emplacement depth of the underlying intrusion, likely resulting in a short-lived character and limited hydrocarbon-generation potential of the associated contact metamorphism. The study demonstrates that Nd isotope analyses of seep carbonates offer a tool in disentangling methane fluxes from different organic matter alteration pathways for the numerous, both fossil and modern sedimented rifts for which the involvement of various methane sources remains insufficiently understood. [ABSTRACT FROM AUTHOR]

Carbonate deposits are numerous and have undeniable economic appeal for the oil industry. However, there are many uncertainties associated with different aspects of these lithologies. Understanding carbonate factories and their global distribution has been a subject of discussion in recent decades, especially concerning the products expected from different carbonate systems, their response to sea‐level variations and the transition between different depositional environments. Therefore, the goal of this study was to understand the role of sea‐level variations, and geodynamics in factories and the evolution of Albian depositional sequences on the south‐east continental margin of Brazil. Fifteen lithofacies consisting of seven facies associations and five third‐order sequences were identified. Sequence boundaries are unconformities formed by erosion or non‐deposition surfaces, representing either exposure periods or drowning events, and their correlative condensed sections. The first sequence, deposited in a shallow lagoon environment, recorded the onset of the T‐factory and the start‐up phase of the shelf. The second sequence represents a period of broad carbonate deposition in the basin, related to the catch‐up phase of the platform. The third sequence was established during a sea‐level rise and recorded the keep‐up phase of the platform and the transition from tropical to cool waters. The fourth sequence, was deposited in a deep marine environment and the fifth and last, recorded the shelf drowning. The succession typifies the beginning, the pinnacle and the end of carbonate deposition, spanning the initial and final highstand system tracts. The whole succession is part of a first‐order transgressive cycle that led to a factory transition and culminated with the definitive drowning of the depositional system. [ABSTRACT FROM AUTHOR]

Nine units of carbonate rocks are recognized, of which the highest five units are examined here under biostratigraphical and chemostratigraphical aspects in order to infer mid‐Cretaceous OAE intervals in Punta China section, Baja California. The biota in Units 5, 6, 7, and 8 show low diversity, while Unit 9 is characterized by a high diversity of microfossils. Benthic foraminiferal assemblage and rudist genera identified in Unit 9 indicate a lower Albian age. Lithofacies and fossil assemblages suggest that the depositional environment was a shallow marine shelf or platform adjacent to caprinid buildups. The limestones of the Alisitos Formation show both negative and positive δ13C values that range between −0.9 and + 7.5‰. Large variations in δ18O values are noticed in the limestone units (−7.9 to −2.2‰). The 87Sr/86Sr ratios of the bulk limestone samples vary between 0.706662 and 0.707305. Most of the limestones have lower 87Sr/86Sr ratios that may be the result of inclusion of less radiogenic strontium from the volcanic rocks. One limestone sample from Unit 7 has a relatively pristine 87Sr/86Sr ratio (0.707305) whose numerical age is 111.61 Ma. The carbon‐isotope curve reveals the presence of two episodes of oceanic anoxic subevents in the studied section. The lower part of Unit 9 has significant negative carbon isotope excursion (CIE) that correlated with the Paquier subevent. Similarly, another negative CIE is also observed in the upper part of Unit 9, which suggests a correlation with Leenhardt subevent. [ABSTRACT FROM AUTHOR]