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Simple Summary: A new fossil praeaulacid wasp, Azygdellitha nova gen. et sp. nov., is described and figured from mid-Cretaceous Kachin amber. This new taxon not only enriches the diversity of praeaulacid wasps from the Kachin amber biota but also provides additional evidence supporting the discussion of a distinct tribe within the subfamily Praeaulacinae. A new praeaulacid genus and species, Azygdellitha nova gen. et sp. nov., is described and illustrated based on a male specimen from mid-Cretaceous Kachin amber from Hukawng Valley, Myanmar. This newly discovered taxon increased the diversity of praeaulacid wasps during the Cretaceous period. While this new taxon shares similarities of wing venation with most species of the subfamily Praeaulacinae, it strongly differs from that of three genera previously described from mid-Cretaceous Kachin amber: Mesevania, Paleosyncrasis, and Praegastrinus. We explore the possibility that these genera constitute a distinct tribe within the Praeaulacinae, distinguished by their wing venation. We provide illustrations and emphasize the potentially diagnostic traits supporting this classification. [ABSTRACT FROM AUTHOR]

Pycnodont fishes were a successful clade of neopterygian fishes that are predominantly found in shallow marine deposits. However, throughout their long 180 million year reign (Late Triassic–end Eocene), they made multiple incursions into both brackish and freshwater environments. This fossil record mostly consists of fragmentary dental material, but articulated specimens are known from Early Cretaceous lacustrine localities in Spain. This review article aims to document all non-marine occurrences of Pycnodontiformes throughout most of the Mesozoic and early Paleogene. This review highlights two interesting trends in the history of non-marine habitat colonization by pycnodonts: (1) a huge spike in non-marine occurrences during the Cretaceous; and (2) that most occurrences in non-marine localities occurred at the latest Cretaceous period, the Maastrichtian. The high number of colonization events within the Cretaceous lines up with extreme climatic events, such as high temperatures resulting in high sea levels which regularly flooded continental masses, allowing pycnodonts easier access to non-marine habitats. The increased presence of pycnodonts in brackish and freshwater habitats during the Maastrichtian might have played a role in their survival through the K/Pg extinction event. Freshwater habitats are not as vulnerable as marine ecosystems to environmental disturbance as the base of their food chain relies on detritus. Pycnodonts might have used such environments as a refuge and began to occupy marine waters after the K/Pg extinction event. [ABSTRACT FROM AUTHOR]

Nypa fruticans (Wurmb), a mangrove palm species with origins dating back to the Late Cretaceous period, is a unique species for investigating long‐term adaptation strategies to intertidal environments and the early evolution of palms. Here, we present a chromosome‐level genome sequence and assembly for N. fruticans. We integrated the genomes of N. fruticans and other palm family members for a comparative genomic analysis, which confirmed that the common ancestor of all palms experienced a whole‐genome duplication event around 89 million years ago, shaping the distinctive characteristics observed in this clade. We also inferred a low mutation rate for the N. fruticans genome, which underwent strong purifying selection and evolved slowly, thus contributing to its stability over a long evolutionary period. Moreover, ancient duplicates were preferentially retained, with critical genes having experienced positive selection, enhancing waterlogging tolerance in N. fruticans. Furthermore, we discovered that the pseudogenization of Early Methionine‐labelled 1 (EM1) and EM6 in N. fruticans underly its crypto‐vivipary characteristics, reflecting its intertidal adaptation. Our study provides valuable genomic insights into the evolutionary history, genome stability, and adaptive evolution of the mangrove palm. Our results also shed light on the long‐term adaptation of this species and contribute to our understanding of the evolutionary dynamics in the palm family. [ABSTRACT FROM AUTHOR]

The Cretaceous Period is a vital time interval in deciphering the evolutionary history of the Neo-Tethys Ocean and the convergence of different plates and blocks across the Qinghai-Tibetan Plateau. A detailed stratigraphic framework and paleogeographic patterns are the basis for understanding the evolution of the Neo-Tethys Ocean and the formation of the Qinghai-Tibetan Plateau. Here, the Cretaceous stratigraphy, biota, paleogeography, and major geological events in the Qinghai-Tibetan Plateau are analyzed to establish an integrative stratigraphic framework, reconstruct the paleogeography during the Cretaceous Period, and decode the history of the major geological events. The Cretaceous rocks of the Qinghai-Tibetan Plateau and its surrounding area are predominantly marine deposits, with a small amount of interbedded marine-terrestrial and terrestrial conponents. The Indus-Yarlung Tsangpo Suture Zone was responsible for the deposition of deep marine sediments dominated by ophiolite suites and radiolarian silicalite. To the south, the Tethys Himalayas and Indus Basin received marine sediments of varying depths and lithology; to the north, the Xigaze and Ladakh forearc basins are also filled with marine sediments. The Lhasa Block, Karakorum Block, western Tarim Basin, and West Burma block consist of shallow marine, interbedded marine-terrestrial, and terrestrial sediments. The Qiangtang Basin and other areas are dominated by terrestrial sedimentation. The Cretaceous strata of the Qinghai-Tibetan Plateau and its surrounding areas are widely distributed and diversified, with abundant foraminifera, calcareous nannofossils, radiolarians, ammonites, bivalves, and palynomorphs. On the basis of integrated lithostratigraphic, biostratigraphic, geochronologic, and chemostratigraphic analyses, we proposed herein a comprehensive stratigraphic framework for the Cretaceous Period of the eastern Neo-Tethys. By analyzing the Cretaceous biota of different biogeographic zones from eastern Neo-Tethys and its surrounding areas, we reconstructed the paleobiogeography of different periods of eastern Neo-Tethys. The Cretaceous paleogeographic evolution of the Qinghai-Tibetan Plateau and its surrounding areas can be divided into three phases: (1) gradual breakup of the Indian Plate from the Australia-Antarctica continent and the early collision phase of the Lhasa-Qiangtang blocks (145–125 Ma); (2) northward drift of the Indian Plate and the collision phase of the Lhasa-Qiangtang blocks (125–100 Ma); (3) rapid northward drift of the Indian Plate, formation of the Tarim-Tajik-Karakorum Bay, and early uplift of the Gangdise Mountains (100–66 Ma). The Indus-Tethys Himalayan biota underwent a transition from the cold-water type in the high latitudes of the southern hemisphere to the warm-water type near the equator from the Early Cretaceous to the Mid-Cretaceous. The biodiversity and abundance of the eastern Neo-Tethys Ocean increased gradually in the Early Cretaceous, peaking in the Mid-Cretaceous, and decreased sharply during the late Late Cretaceous (late Maastrichtian). Along with the northward drift of the Indian Plate and subduction of the Neo-Tethys, the eastern Neo-Tethys and its surrounding areas experienced a series of major geological events, including the formation of the large igneous province, oceanic anoxia events, and mass extinction, etc. [ABSTRACT FROM AUTHOR]

Source rock evaluation and basin modelling play crucial roles in understanding hydrocarbon potential. In this study, pyrolysis data from 92 shale ditch samples were employed to assess the source rocks in the Abu Gharadig Basin (Western Desert, Egypt). The organic richness ranged from 0.53% to 4.1% by weight, indicating varying hydrocarbon‐generating capabilities. Specifically, kerogen types II and III exhibited the potential to generate hydrocarbons, ranging from fair to good oil sources. The burial history analysis provided insights into the sedimentation and subsidence rates during different geological periods. The Late Jurassic‐Early Cretaceous period witnessed modest rates of sedimentation and subsidence. In contrast, the Oligocene and Late Miocene periods experienced medium burial rates, while the Late Cretaceous‐Early Tertiary period exhibited high burial rates. Specific formations were examined in detail, with the Apollonia Formation standing out as a significant hydrocarbon reservoir. It entered the early oil window at approximately 17.87 Ma and the wet gas window at about 17.41 Ma in the ASSIL‐1X well. However, it didn't reach the GPAA‐4 well. The Abu Roash 'D' member also showed promise, entering the early oil window at 38.20 and 47.38 Ma, and the wet gas window at 37.40 and 43.64 Ma. Similarly, the Abu Roash 'F' member exhibited favourable hydrocarbon generation, entering the early oil window at 39.90 and 54.86 Ma, and the wet gas window at 39.70 and 51.62 Ma in both the ASSIL‐1X and GPAA‐4 wells. Based on the analysis, the Apollonia, Abu Roash 'D' and 'F' members were identified as source rocks, while the Kharita, 'C', 'E' and 'G' members were recognized as reservoir rocks. The Abu Roash Shale acted as an effective seal rock. The geological structure of the region revealed the presence of NW‐SE normal faults, forming a three‐way dip closure trap. This research substantially enhances our comprehension of the hydrocarbon system within this basin. It achieves this by thoroughly investigating source rock evaluation, basin modelling and delivering invaluable insights into the mechanisms that govern hydrocarbon generation, expulsion and trap age. [ABSTRACT FROM AUTHOR]

Although the fossil record of turtles in the Cretaceous of Patagonia is diverse and abundant, the record from the Austral-Magallanes Basin (Santa Cruz Province, Argentina, and Magallanes Region, Chile) is scarce and fragmentary. This contribution presents a new record of a turtle from the Piedra Clavada Formation (early Cenomanian) found near Tres Lagos Village, Santa Cruz Province, Argentina. This new fossil is characterized by a unique combination of character states: medium-sized carapace (length circa 50 cm), shell with a smooth surface, having narrow vertebral scutes, regular neural bones longer than wide, the tips of thoracic ribs seen in dorsal view, posterior marginals reaching costal bones, and not having costo-peripheral fontanelles. Furthermore, based on paleolatitudinal reconstructions, the new turtle from the Piedra Clavada Formation lived in the circumpolar region (54º S), representing the oldest southernmost record of turtles in the Late Cretaceous of South America. Considering this unique combination of characters and the comparison with other Early--early Late Cretaceous turtles from Gondwana, we can suggest that MSV103 does not only belong to a new species but a new, previously unrecognized lineage of turtles in southern Patagonia [ABSTRACT FROM AUTHOR]

The mineralogy and chemistry of Upper Cretaceous-Lower Paleocene claystone sediments from Mardin and Batman, southeastern Turkey, were analyzed. The main mineral paragenesis in the Upper Cretaceous member formed chlorite-smectite (C-S) and illite, while the Lower Paleocene member occurred of chlorite-vermiculite (C-V) and vermiculite minerals. The clays were silica-poor but indicated high values of Al, Fe, Mg, Cr, Ni, V, and Zr. Lower contents of the alkali elements (Na, Ca, Mg, K) of the clayey sediments suggests a relatively denser weathering of the source area. The mineralogical compositions, major element ratios, trace, and rare earth element (REE) contents of the sediments show that the Upper Cretaceous member consists of materials with a mainly felsic source lithology, while relatively contributions from basic sources are found in the Lower Paleocene unit. A comparison of the major and trace element contents of the phyllosilicate/clay minerals with the members revealed that the patterns of the clays were different from each other, although the enrichments/decreases varied depending on the origin (basement rocks or detrital) of the derived rocks, minerals, and elements. REE content of clays increased from detrital to phyllosilicate/clay minerals of chemical/diagenetic/neoformation origin during the Lower Paleocene. During the Cretaceous and Tertiary periods, local or regional geodynamic and diagenetic events largely governed the rock sedimentation processes and provenance variations amongst Germav Formation members. [ABSTRACT FROM AUTHOR]

Caturoidea is a clade of Mesozoic predatory ray-finned fishes which lived mainly in the Jurassic. The clade has a few records in the earliest Cretaceous and only two in the Triassic. Among the latter, specimen MPCA 632 Caturus sp. doubtfully from continental Early Triassic of Argentina, i.e., outside Europe, was particularly problematic in the light of the known fossil record of the group, which suggested their origin in the Western Tethys. The micropaleontological and geochemical analysis of bulk-rock samples of MPCA 632 allowed us to correct the provenance of the specimen which corresponds to Tithonian marine outcrops of the Vaca Muerta Formation, Neuquén, Argentina. Specimen MPCA 632 is excluded from Caturus and reclassified as Caturoidea sp. MPCA 632 might be a specimen of Catutoichthys olsacheri, the only caturoid known from the Vaca Muerta Formation (Los Catutos Member), but the fossils are not comparable and, thus, this hypothesis needs further study. Additionally, the first-hand study of the type material of the only other alleged Triassic caturoid, Furo insignis, in the Norian of Seefeld, Austria, led to the exclusion of this taxon from the Caturoidea. Consequently, the clade Caturoidea is restricted to the Jurassic--Lowest Cretaceous. After a modest evolution during the Early Jurassic, the group had its initial radiation and westward dispersion across the Hispanic Corridor during the Middle Jurassic and reached its maximal diversity during the Kimmeridgian and Tithonian. [ABSTRACT FROM AUTHOR]

A unique petrified tree fern displaying distinct patterns was recently discovered in northeast China, attracting considerable interest. This study provides a comprehensive set of data for this material obtained through standard gemological testing, petrographic observation, scanning electron microscopy, energy-dispersive spectroscopy, electron probe microanalysis, and Raman spectroscopy. The petrified tree fern exhibits colors ranging from golden yellow to brown, with additional variations caused by iron oxides. Chalcedony is the primary mineral component, while the presence of metastable moganite gives chalcedony its fibrous nature, contributing to the delicate structure of the samples. The surface pattern originates from plant structures preserved during silicification, further confirming the samples belong to the extinct Cretaceous period tree fern Tempskya sp. [ABSTRACT FROM AUTHOR]

The clumped isotope paleo-thermometer has become a valuable proxy for the burial history reconstruction of carbonate formations. To maximise the accuracy of these reconstructions, post-depositional alterations, such as recrystallisation and Δ47 isotope exchange reactions, must be understood. In this study, we examine the isotopic behaviour of calcites and early dolomite samples from the same stratigraphic intervals, and thus with similar burial history. This approach provides additional constraints on the kinetics of Δ47 reordering in dolomite during exhumation. Clumped isotope measurements were performed on 19 calcites and 15 early dolomites from the Permian, Jurassic, and Cretaceous periods from four locations in Oman spanning different burial regimes. The calcite and dolomite samples were collected from the rock matrix, based on the assumption that fine material was more susceptible to recrystallisation. Our results show that calcites and dolomites record different Δ47 values despite being subjected to the same thermal history. The maximum Δ47 temperature recorded in dolomites (181 ± 13 °C) corresponds to the oldest and most deeply buried Permian rock. This value is approximately 35 °C higher than those measured in the co-located and coeval calcite matrix (145 ± 14 °C). This discrepancy suggests that calcite and dolomite have different kinetic parameters. Our data confirm (1) that dolomite Δ47 values are more resistant to alteration during burial and exhumation than Δ47 calcite values, and (2) that dolomite has a higher Δ47 closing temperature than calcite during cooling. The presence of two mineral phases with distinct kinetic parameters in the same stratigraphic unit provides additional constraints on models of burial and uplift. In addition, mineralogical data coupled with Δ47 and burial depths suggest that the progressive development of dolomite cation ordering is driven by temperature elevation, as previously suggested. [ABSTRACT FROM AUTHOR]

Gomphomastacinae is a grasshopper subfamily in Eumastacidae, with a morphology and distribution distinct from other subfamilies. The alpine genera of Gomphomastacinae that inhabit the Qinghai–Tibet Plateau in China show unique characteristics adapted to high‐altitude life. However, their phylogenetic position and biogeographic history remain controversial. Thus, to determine the diversification history of these alpine genera and the origin of the subfamily, we obtained mitochondrial genome sequences from all seven Gomphomastacinae genera distributed in China. The reconstructed phylogeny was well supported and confirmed the phylogenetic position of Gomphomastacinae within Eumastacidae. Time calibration revealed a deep‐time origin of the subfamily dating back to the Cretaceous period, and the diversification among alpine genera was also an ancient pre‐Miocene event (30–50 Ma). Based on phylogeny and time estimates, the most likely biogeographic scenario is that Gomphomastacinae originated from an ancestral lineage that lived in East Gondwana and dispersed to Central and Western Asia through India. Subsequently, the alpine genera likely diverged along with the uplift of the Qinghai–Tibet Plateau and survived drastic climate change by in situ adaptation to high‐altitude dwellings. [ABSTRACT FROM AUTHOR]

The Indian Mesozoic dinosaur record is famous for documenting significant aspects of dinosaur evolution during the Triassic, Jurassic and Cretaceous periods. The Cenomanian-Turonian Nimar Sandstone, Lower Narmada valley, has produced fragmentary skeletal remains of Sauropoda indet. The Maastrichtian Lameta Formation has yielded at least 5 valid sauropod taxa and indeterminate titanosaurid remains, and at least 11 named (but likely oversplit) theropod taxa, i.e., 3 smaller-bodied species and 8 medium-to-large sized theropods. Apart from skeletal remains, Infra- and Intertrappean beds of peninsular India have yielded more than 10,000 dinosaur eggs belonging to 5 oofamilies and 15 oospecies. Most of the Indian ootaxa show distinct affinities with the Late Cretaceous ootaxa of four other continental areas - Spain, France, Argentina and Morocco. The presence of the two dominant oofamilies, Fusioolithidae and Megaloolithidae, in the Infra- and Intertrappean localities of peninsular India and three different continents (South America, Europe and Africa) further shows an ancient Gondwanan affinity and basic terrestrial association among these three landmasses. Based on the phylogenetic analysis of skeletal material, the most plausible pathway of dinosaur dispersal between India and Madagascar took place during the Late Cretaceous. The other conceivable dispersal pathway for the small animals was between India and Asia by means of the Kohistan Dras Volcanic Arc or a northeast pathway through Somalia, while the very large vertebrates, like theropod dinosaurs, may have emerged as a component of a 'Pan Gondwanan' model. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to further advance our understanding of the species‐rich, and ecologically important angiosperm family Combretaceae to provide new insights into their evolutionary history. We assessed phylogenetic relationships in the family using target capture data and produced a dated phylogenetic tree to assess fruit dispersal modes and patterns of distribution. Location: Tropical and subtropical regions. Time Period: Cretaceous to present. Major Taxa Studied: Family Combretaceae is a member of the rosid clade and comprises 10 genera and more than 500 species, predominantly assigned to genera Combretum and Terminalia, and occurring on all continents and in a wide range of ecosystems. Methods: We use a target capture approach and the Angiosperms353 universal probes to reconstruct a robust dated phylogenetic tree for the family. This phylogenetic framework, combined with seed dispersal traits, biome data and biogeographic ranges, allows the reconstruction of the biogeographical history of the group. Results: Ancestral range reconstructions suggest a Gondwanan origin (Africa/South America), with several intercontinental dispersals within the family and few transitions between biomes. Relative abundance of fruit dispersal types differed by both continent and biome. However, intercontinental colonizations were only significantly enhanced by water dispersal (drift fruit), and there was no evidence that seed dispersal modes influenced biome shifts. Main Conclusions: Our analysis reveals a paradox as drift fruit greatly enhanced dispersal distances at intercontinental scale but did not affect the strong biome conservatism observed. [ABSTRACT FROM AUTHOR]

Background and Aims CAM photosynthesis is hypothesized to have evolved in atmospheres of low CO2 concentration in recent geological time because of its ability to concentrate CO2 around Rubisco and boost water use efficiency relative to C3 photosynthesis. We assess this hypothesis by compiling estimates of when CAM clades arose using phylogenetic chronograms for 73 CAM clades. We further consider evidence of how atmospheric CO2 affects CAM relative to C3 photosynthesis. Results Where CAM origins can be inferred, strong CAM is estimated to have appeared in the past 30 million years in 46 of 48 examined clades, after atmospheric CO2 had declined from high (near 800 ppm) to lower (<450 ppm) values. In turn, 21 of 25 clades containing CAM species (but where CAM origins are less certain) also arose in the past 30 million years. In these clades, CAM is probably younger than the clade origin. We found evidence for repeated weak CAM evolution during the higher CO2 conditions before 30 million years ago, and possible strong CAM origins in the Crassulaceae during the Cretaceous period prior to atmospheric CO2 decline. Most CAM-specific clades arose in the past 15 million years, in a similar pattern observed for origins of C4 clades. Conclusions The evidence indicates strong CAM repeatedly evolved in reduced CO2 conditions of the past 30 million years. Weaker CAM can pre-date low CO2 and, in the Crassulaceae, strong CAM may also have arisen in water-limited microsites under relatively high CO2. Experimental evidence from extant CAM species demonstrates that elevated CO2 reduces the importance of nocturnal CO2 fixation by increasing the contribution of C3 photosynthesis to daily carbon gain. Thus, the advantage of strong CAM would be reduced in high CO2, such that its evolution appears less likely and restricted to more extreme environments than possible in low CO2. [ABSTRACT FROM AUTHOR]

Large igneous provinces (LIPs) are major magmatic events that have a significant impact on the global environment and the biosphere, for example as triggers of mass extinctions. LIPs provide an excellent sedimentological and geochemical record of short but intense periods of geological activity in the past, but their contribution towards understanding ancient life is much more restricted due to the destructive nature of their igneous origin. Here, we provide the first paleontological evidence for organic walled microfossils extracted from wet peperites from the Early Cretaceous Paraná-Etendeka intertrappean deposits of the Paraná basin in Brazil. Wet peperites are a volcaniclastic rock formed by the interaction of lava and subaqueous sediments.The Paraná-Etendeka was formed during the Valanginian (ca. 132 Ma) as a continental flood basalt in present day South America and Namibia, and released enormous amounts of carbon dioxide, sulfur dioxide, methane and hydrogen fluoride into the atmosphere. The organic walled microfossils recovered from the Paraná-Etendeka peperites include pollen grains, spores, acritarchs, and other remains of unidentifiable organic matter. In addition to the peperites, organic walled microfossils were also found in heterolithic sandstones and interpillow sandstones. Our findings represent the first insight into the biodiversity of the Paraná Basin during the Early Cretaceous during a period of intense magmatism, and the microfossil assemblages corroborate a regional paleoclimatic transition from arid to more humid conditions that were likely induced by the volcanic activity. We corroborate the potential of wet peperite rocks as a valuable source of paleobiological data and emphasize the importance of sampling volcaniclastic units that have been traditionally considered with lower fossiliferous potential due to their igneous origin. [ABSTRACT FROM AUTHOR]

Aim: Leaves display a remarkable variety of shapes, each with potential ecological advantages in specific climates. While the relations between leaf shape and either climate or height have been relatively well studied in eudicots, the macroecological drivers of shape remain poorly known in monocots. Here, we investigated the associations between climate and plant height with the evolution of leaf shape in a clade with high species and morphological diversity. Location: Global. Time period: Cretaceous to contemporary. Major taxa studied: Palms (Arecaceae). Methods: We apply a Bayesian phylogenetic mixed model to test for associations between climate and leaf shape (all – entire‐leaved, pinnate‐dissected, palmate‐dissected and costapalmate). We further reconstruct the ancestral leaf shape using multistate speciation and extinction models and compare the frequency of shapes with global temperatures through time. Results: We find that plant height associates with dissected leaves and that annual precipitation associates with pinnate shapes. The ancestral leaf shape is unclear, but early diversification was dominated by pinnate‐dissected palms, which has remained the most species‐rich form of leaves throughout palm history. Main Conclusions: Palms that are tall and live in humid regions are more likely to have pinnate leaves. Through geological time scales, temperature did not play an obvious role in determining leaf shapes. This study contributes to our understanding of how the diversity of leaf shapes is linked to biological and climatic factors. [ABSTRACT FROM AUTHOR]

Northwest Zhejiang area (NWZJ) is one of the important parts of the large Qingzhou-Hangzhou mineralized belt in South China formed during the Late Jurassic–Early Cretaceous period. Through the study of zircon LA-ICPMS U-Pb dating, whole-rock geochemistry, and Sr-Nd isotopes for the Wujinshan granitoid in NWZJ, two distinct S-type granitic rocks of porphyry type granodiorite and granite were identified, and the two ages of 146.4 ± 1.5 Ma for granodiorite porphyry and 141.9 ± 1.4 Ma for granite porphyries were obtained. These rocks exhibited a geochemical affinity for S-type granitoid, and the two magmatic ages indicate that these rocks were intruded in two magmatic pulses. The Late Jurassic granodiorite porphyry showed moderate SiO2 (64.38–67.89 wt.%) with higher K2O + Na2O (6.22–6.78 wt.%), lower K2O/Na2O (0.57–0.96), moderate Zr (170–215 ppm), high Sr (302–475 ppm), and low Mg# (31–32) contents. The Early Cretaceous granite porphyries contained high SiO2 (69.68–74.85 wt.%), variable K2O + Na2O (4.60–6.99), high K2O/Na2O (1.72–23.53), slightly higher Zr (160–255 ppm), variable Sr (25–412 ppm), and very low to intermediate Mg# (13–44). The granodiorites had intermediate ∑REE (149–177 ppm), while granite samples showed moderate to high ∑REE content (147–271 ppm), and both rocks showed negative Eu anomalies (0.18–0.29). We propose that these two rocks were predominantly generated by the partial melting of Mesoproterozoic metamorphic basement and underwent variable degrees of fractionation and evolution. The Late Jurassic granodiorite porphyry was formed by the partial melting of Mesoproterozoic metamorphic basement with slab-derived melts or basaltic lower crust input following fractional crystallization, while the Early Cretaceous granite porphyries were generated by the partial melting of Mesoproterozoic metamorphic basement and crystal fractionation with variable magma mixing and assimilation in the upper crust. Tectonically, the Wujinshan granitoid formed in a volcanic arc setting largely affected by the subduction and slab rollback of the paleo-Pacific Plate. [ABSTRACT FROM AUTHOR]

Several models exist concerning the deformation history of the Pontides in North Anatolia during the Cretaceous period, which vary depending on the positions of the Istanbul and Sakarya zones, the consumption of the northern branches of the Neotethys ocean and the rifting of several sub-basins. Notably, the early Cretaceous tectonic history of the Pontides involved the closure of the northern Neotethys ocean (Intra-Pontide ocean), and the collision between the Istanbul and Sakarya zones, producing thrust structures along the collisional front. The lack of palaeomagnetic data providing evidence for this deformation pattern demonstrates that further investigation is required, particularly focusing on the Lower Cretaceous strata in the Pontides. Thus, this study aimed to examine samples from a total of 78 sites from the Lower–Upper Cretaceous sedimentary rocks, and Middle Eocene to Middle Miocene sedimentary and volcanic rocks. Results of this study indicated large counterclockwise rotations up to R ±Δ R = −73.9°±9.1°, and small clockwise rotations of R ±Δ R  = 14.2°±12.2° in the Istanbul and Sakarya zones, during the Early Cretaceous and Late Cretaceous periods. These rotation patterns are accompanied by the closure of the Intra-Pontide ocean, and the collision between the Istanbul and Sakarya zones during the Early and Late Cretaceous periods. On the other hand, in the Middle Eocene, small counterclockwise rotations of R ±Δ R = −6.4°±13.9° and 4.6°±12.9° along the western coastline of the Pontides indicated that the northern margin of the Pontides was stable during this period. [ABSTRACT FROM AUTHOR]

A molecular phylogenetic investigation was undertaken for 30 species belonging to 15 genera of the palm family Arecaceae in Bangladesh to infer evolutionary relationships and molecular dating utilizing plastid-based matK and rbcL genes through multifacetedalgorithm driven approaches with Neighbor-Joining, Maximum-Likelihood, and Bayesian Inference methods. The study revealed that matK has better species discrimination efficiency than rbcL gene due to its highly variable nature. Transition/transversion bias test corroborated this finding as matK showed higher bias (2.632) than rbcL (2.235). Nucleotide substitution patterns were visualized via HYPERMUT program, which unveiled higher variability in matK and lower variability in rbcL alignment. Phylogenetic trees constructed with matK revealed monophyletic nature of origin for all the three subfamilies, viz. Arecoideae, Coryphoideae and Calamoideae, while rbcL trees exhibited polyphyly for Coryphoideae and monophyly for Arecoideae and Calamoideae. All the nine tribes belonging to three subfamilies demonstrated monophyletic nature in matK trees. Bootstrap support and Bayesian posterior probability were found to be higher in matK topologies than that of rbcL. The molecular clock test unraveled an equal evolutionary rate for matK and unequal rate for rbcL sequences. Molecular dating approach unveiled Calamoideae to be the most ancient subfamily (65.75 MYA) among the three subfamilies that originated during the Late Cretaceous period in the Mesozoic era, whereas Coryphoideae and Arecoideae were found to have originated in the Cenozoic era. [ABSTRACT FROM AUTHOR]

The Coniacian-Santonian series in the Aures Mountains of northeastern Algeria is characterized by marly-dominated sedimentation processes. This study aims to comprehensively investigate this series by combining lithostratigraphic and biostratigraphic data. The unique paleogeographic position of the Aures basin supports the co-occurrence of diverse paleontological contents in the Upper Cretaceous sediments. The methodology employed in this study includes a detailed bio-lithostratigraphic analysis to subdivide the Coniacian-Santonian series into two distinct sets. The first set comprises alternating marl-limestone units that exhibit a high fossil concentration from the Coniacian age, while the second set mainly consists of marly sediments corresponding to the Santonian age. The results obtained from this study highlight the geographical distribution of litho-biostratigraphic characteristics and reveal the presence of two formations. The lower formation is characterized by carbonated marls intercalated with limestone banks, containing fossils of Peroniceras (Tissotia tissoto) from the Coniacian age. Meanwhile, the upper formation is predominantly marly and indicates the Santonian age by displaying fossils of Palcenticeras polypsis. Furthermore, a biostratigraphic analysis focused on foraminifers allows for the subdivision of the Coniacian-Santonian series in the Aures Mountains into three distinct biozones. The first biozone corresponds to the lower Coniacian age and is identified by the presence of Dicarinella primitiva. The second biozone represents the middle to upper coniacian age and contains Dicarinella concavata fossils. Finally, the third biozone, belonging to the Santonian age, is marked by the occurrence of Dicarinella asymetrica. The boundary between the Coniacian and Santonian series in the Aures Mountains is characterized by the first appearance of Dicarinella asymetrica and Palcenticeras polypsis species. This multidisciplinary study provides valuable insights into the litho-biostratigraphic characteristics and geographical distribution of the Coniacian-Santonian series in the Aures Mountains. The findings make a significant contribution to a better understanding of sedimentary processes and the paleontological content within this region during the Upper Cretaceous period. [ABSTRACT FROM AUTHOR]

Acteonellids were one of the most significant groups of marine macro-invertebrates in the Late Cretaceous biota of the Tethyan Realm. They were common faunal elements associated with Cretaceous carbonate platform communities most notable for their abundance of rudist frameworks and thrived in coeval lagoons. The Upper Cretaceous fossil-bearing Karababa Formation, cropping out in southeastern Turkey, yields a remarkable assemblage of acteonellid gastropods and rudists. Cretaceous gastropods from sedimentary successions in Turkey barely have been studied over the past 80 years. The subgenus Trochactaeon, a very successful and widespread taxon of heterobranch gastropods within the family Acteonellidae, dominated acteonellid assemblages throughout the Late Cretaceous. In the present work, we present the first record of Trochactaeon (Trochactaeon) giganteus subglobosus from Turkey. It is from a single lower Campanian bed in the upper part of the Karababa Formation of the Gölbaşı region (south of Adıyaman), corresponding to the northwestern part of the Arabian Platform. This record complements information on the temporal and spatial distribution of Trochactaeon at the southern margin of the Tethyan Ocean during the last part of the Cretaceous Period. This discovery increases the documented diversity of the paleofauna from the Upper Cretaceous succession in southeastern Turkey and provides new insights into the paleoenvironment of the carbonate ramp of the northern Arabian plate, and the paleobiogeography of Campanian gastropods in general. [ABSTRACT FROM AUTHOR]

The Lianhuashan metallogenic belt in Eastern Guangdong Province (South China) is the most important Sn polymetallic district in the region, hosting many medium-sized deposits such as the Tashan, Xianshuili, and Jiangxikeng. However, the metallogenic mechanism of these deposits remains hotly debated. In this paper, two types of cassiterites (Cst1 and Cst2) have been identified in the Xianshuili and Jiangxikeng Sn deposits, which are hosted in the biotite-mylonite and garnet-cordierite-muscovite blastomylonite, respectively. The euhedral Cst1 (0.50–1.8 mm) coexists with biotite, feldspar, and quartz. It is platy and zoned with a mosaic structure. The subhedral to anhedral Cst2 (0.02–0.35 mm) coexists with metamorphic minerals such as garnet and cordierite, and it is characterized by well-developed porosity and has no zonation. In-situ U-Pb dating of the Cst1 and Cst2 yielded ages of 149.5±1.0 Ma (MSWD=1.6, n=45) and 125.1±2.3 Ma (MSWD=4.5, n=43), respectively. Cst1 is most likely to be related to the intermediate-felsic magmatism that formed Gaojiping Group, whereas Cst2 has relatively high Ta, Nb, Fe, and W contents with obvious rare earth tetragroup effect, and may have formed by the late Early Cretaceous dynamic metamorphism. Results presented here, when combined with regional geology and geochemistry, led us to suggest that the Mesozoic intermediate-felsic volcanic rocks in the LMB are significantly enriched in Sn and F, with high Sn-polymetallic mineralization potential which likely have contributed to the volcanic-related Cst1. In the late Early Cretaceous period, due to the NW-dipping subduction of the paleo-Pacific plate, the intermediate-felsic volcanic rocks underwent dynamic metamorphism that led to Sn mobilization, migration, and precipitation in the regional ductile shear zones, and eventually generating Sn mineralization. We propose that areas beneath Xianshuili and Jiangxikeng have great potential for discovery of new Sn resources. Our findings likely offer practical importance to regional geological ore prospecting. [ABSTRACT FROM AUTHOR]

U-Pb dating of single detrital zircon grains by laser ablation--inductively coupled plasma--mass spectrometry (LA-ICP-MS) paired with Hf and O isotopic and trace-element analyses provide first-order indicators of the Late Cretaceous--Cenozoic evolution of the southern Ecuadorian magmatic arc. Detrital zircon U-Pb ages define significant clusters that are tentatively interpreted as intense arc magmatism at ca. 72 Ma, ca. 60 Ma, and ca. 43 Ma. A major accretionary event in the Late Cretaceous (75-65 Ma) is marked by a broad range of zircon isotopic values (εHf[t] > 20 and δ18O > 8‰) that suggest melting of both the lower and upper crust (most likely of continental affinity) as well as enriched mantle components. Highly fractionated signatures in trace-element patterns and Eu/Eu* combined with mantle-like δ18O and juvenile εHf values characterize zircons from 60 to 45 Ma, suggesting that the Late Cretaceous--middle Eocene arc originated from an enriched mantle and likely reflects the persistence of overthickened crust previously attributed to the main Late Cretaceous accretionary period. Subsequently, negative shifts in εHf(t) isotopic composition from 45 to 30 Ma are paired with mantle-like δ18O values as well as decreases in U/Yb and Eu/ Eu*. These signatures could be attributed to magma emplacement in a thinner crust and the existence of a broad extensional magmatic arc extending from the current forearc toward areas near the craton; however, other scenarios cannot be excluded. This event was characterized by enriched mantle melt sources with residence times pointing to known crustal events (Sunsás) in the Amazonian craton. From 30 to 10 Ma, the isotopic record slightly evolved toward a depleted mantle signature with a substantial increase in fractionation. Our results combined with previously published isotopic records from detrital zircon grains found in modern rivers suggest that, for at least the last 30 m.y., the southernmost Northern Andes magmatic arc has been segmented, with the emplacement of juvenile magmas to the north and more enriched magmas related to the recycling of ancient continental crust and/or subducted sediments to the south--aspects found in other Northern Andes settings in which the continental arc was constructed in both oceanic and continental crust. [ABSTRACT FROM AUTHOR]

The superlarge Huaaobaote Ag–Pb–Zn deposit is located on the western slope of the southern Great Xing'an Range (SGXR). The deposit includes four ore blocks, namely, ore blocks I, II, III, and V. Except for the no. I orebody of ore block I, which is hosted in the contact zone between the Carboniferous serpentinized harzburgite and the Permian siltstone, the other orebodies all occur as veins controlled by faults. The mineralization process at the deposit can be divided into four stages: cassiterite–arsenopyrite–pyrite–quartz stage (stage I), cassiterite–chalcopyrite–pyrite–freibergite–arsenopyrite–pyrrhotite–quartz stage (stage II), sphalerite–galena–jamesonite–stibnite–freibergite–silver mineral–quartz–calcite–chlorite stage (stage III), and argentite–pyrargyrite–pyrite–quartz–calcite (stage IV). Cassiterite U–Pb dating of the Huaaobaote deposit yielded ages of 136.3–134.3 Ma, indicating that the deposit formed in the Early Cretaceous period. Two types of fluid inclusions (FIs), including liquid-rich and gas-rich FIs, have been distinguished in the quartz vein and sphalerite. The homogenization temperature during the four stages gradually decreases, with temperatures of 302–340 °C for stage I, 267–304 °C for stage II, 186–273 °C for stage III, and 166–199 °C for stage IV, respectively. The salinity (wt% NaCl eqv.) at stages I, II, III, and IV is 3.7–6.6, 0.2–4.5, 0.2–5.0, and 0.4–1.6, respectively, indicating that the ore-forming fluid is characterized by low salinity. The δ18Owater and δD values of the ore-forming fluid range from −11.9‰ to 7.9‰ and −168‰ to −76‰, respectively, indicating that the ore-forming fluid was dominantly derived from a mixture of magmatic and meteoric water. The calculated δ34SH2S values range from −3.6‰ to 1.2‰, indicating that the sulfur mainly came from granitic magma. The 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios of sulfides are in the ranges of 18.195–18.317, 15.509–15.667, and 37.965–38.475, respectively, implying that the ore-forming material was mainly derived from felsic magma that may be formed by the partial melting of orogenic materials. Fluid mixing, cooling, and immiscibility were the three primary mechanisms for mineral precipitation in the Huaaobaote deposit. [ABSTRACT FROM AUTHOR]

This document is an editorial from the journal "Viruses" discussing tobamoviruses, which are plant-infecting viruses with an ancient lineage dating back to the Cretaceous period. Tobamoviruses are known for their resilience and ability to remain viable for long periods of time. Some tobamoviruses pose a threat to crops, and efforts are being made to understand their transmission and develop biosecurity measures. The editorial highlights several research papers on topics such as the host range of cucumber green mottle mosaic virus, the transmission of tomato brown rugose fruit virus, and the effectiveness of biosecurity measures in Australia. Additionally, the editorial mentions a study on using tobamovirus particles for biomedical applications. The author concludes by acknowledging that more tobamoviruses will likely be discovered in the future, presenting both challenges and opportunities for scientists. [Extracted from the article]

Phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae) have biological relevance as vectors of several pathogens. To ensure periodic entomological monitoring it is necessary to have efficient and accurate tools for an adequate taxonomic identification. There are only few studies on phylogenetic analyses of phlebotomine sand flies from Neotropics, based mostly on morphological and/or molecular data, which makes the delimitation of intra- and interspecific variability of species challenging. Here we generated new molecular information on sand fly species distributed in endemic areas of leishmaniasis in Mexico, using mitochondrial and ribosomal genes, and incorporating morphological information available. Specifically, we established their phylogenetic relationships, and estimated their divergence time. Our study provides molecular information for 15 phlebotomine sand fly species from different areas of Mexico, contributing to the genetic inventory and phylogenetic relations among Neotropical species of the subfamily Phlebotominae. Mitochondrial genes proved to be suitable markers for the molecular identification of phlebotomine sand flies. However, the incorporation of additional nuclear gene information could increase the significance of phylogenetic inferences. We also provided evidence about a possible divergence time of phlebotomine sand fly species, supporting their presumable origin in the Cretaceous period. [ABSTRACT FROM AUTHOR]

A gravity survey was carried out to estimate the sedimentary thickness and to map upper crustal geometry over the northern part of the Cambay rift. Structural lineaments delineated using the total horizontal gradient of the Bouguer anomaly indicate a major lineament trend in the NW-SE direction. Results of the density modelling using residual Bouguer anomaly reveal the average thickness of the Quaternary and Tertiary sediments to be between 0.5 and 6 km, while the Deccan trap thickness varies between 0.5 and 3 km. It is seen that the Mesozoic sediment (maximum thickness ∼0.6 km) is sandwiched between the Deccan trap and granitic basement, which indicates the possible existence of a rift in the late Jurassic-early Cretaceous. Based on the residual Bouguer and density modelling results, the spatial locations of the NE-SW trending Unhawa ridge and the N-S trending Mehsana uplift are provided, which are believed to be the remnant rock of the Proterozoic age. A high-density body, interpreted as a magmatic underplating layer, is also found in the lower part of the middle crust along the central part of the rift, which continues in the lower crust. The magmatic underplating layer is formed during the Reunion hotspot and lithospheric interaction in the Cretaceous period. [ABSTRACT FROM AUTHOR]

Many geophysical and geological data have been used to interpret the tectonic evolution of the south-eastern part of the Tunisian margin and to analyze the dominant structures in the area. The Menzel Habib Plain (MHP) and surroundings, targeted by this study, exhibits thick siliciclastic and carbonate formations attributed to the Early Cretaceous period. Integration of seismic and gravimetric data coupled with analysis of the syndepositional faults affecting these formations prove that the Tunisian margin is dominated, during this period, by N-S to NE-SW extensional directions. The geodynamic evolution of the MHP is mainly due to the irregular normal movement of the N-S faults, which represents the southernmost branch of the N-S Axis (NSA) and of the NW-SE faults, which constitutes the SE segment of the South Atlasic fault corridor (SAFC). In addition, the NE-SW and E-W oriented faults contributed to this evolution. Over extensive periods, this network of faults determines horst and grabens basin geometry or tilted blocks inducing formation of several distinct areas with different subsidence rates. Simultaneously, the normal activity of the major faults promotes the vertical mobilization of the Triassic salt resulting in the individualization of several diapiric bodies, some of which pierced their sedimentary cover. These dynamics reflect echoes of the sinistral drifting of Africa with respect to Europe, integrated in a long Tethyan rifting cycle, and the beginning of opening of the Mesogean Sea, respectively. [ABSTRACT FROM AUTHOR]

The Anambra Basin has a relatively high hydrocarbon production base compared with other Cretaceous basins in Nigeria. Structural deformation, overpressures, and faulting in the Cretaceous sequence of the Anambra Basin have resulted in significant uncertainties regarding reservoir parameters, necessitating accurate reservoir characterization. This study uses several subsurface data, including 2D seismic data, a report of core descriptions, and well log data from an exploration well drilled in the Anambra Basin to identify reservoirs and assess the petrophysical parameters of Cretaceous Formations for hydrocarbon accumulations. Three reservoirs were identified in the interpreted seismic section of the Cretaceous strata, and the structural framework was described as a system of synthetic faults dipping north-south that controlled the thickness and lateral extension of the deposited sediments. The shale volume, total and effective porosity, permeability, water, and hydrocarbon saturation were estimated using standard equations. The low shale volume, good-to-very good porosity values, fair-to-moderate permeability values, and low-tomoderate hydrocarbon saturation of the identified Cretaceous reservoirs suggest that the reservoir sands have the capacity to produce hydrocarbons. The density-neutron cross-plots of the identified reservoirs show a dual mineral system and also indicate the effect of gas in the Cretaceous reservoirs. This study found that the Anambra Basin has gas potential. However, the identified gas reservoirs should be further evaluated using reservoir pressure data, if available, to aid in accurate hydrocarbon fluid typing. The reservoirs should be developed and optimized in such a way as to keep production risk to its minimum. [ABSTRACT FROM AUTHOR]

In the geological history of the Earth, there has been a significant change in the composition and areas of carbonate accumulation, which reflects the general evolution of the formation of carbonate deposits, paleogeographic and geochemical settings, and different stages of this evolution. At the Archean–Proterozoic boundary, acidic conditions in water reservoirs changed to moderately acidic, which resulted in the appearance of iron carbonates. The second milestone is the Siderian–Rhyacian boundary, when intensive assimilation of CO2 led to the development of alkaline conditions in water reservoirs and the accumulation of Mg carbonates. Carbonate accumulation itself occurred in the inland water reservoirs. The third milestone is the Vendian–Cambrian boundary, when skeletal fauna appeared, and carbonate accumulation became largely biogenic. Along with the basins of the continental block, there appeared new oceanic areas of carbonate accumulation, where the skeletons of nekton organisms became a significant supplier of material. The fourth milestone—the Paleozoic–Mesozoic—was the beginning of the accumulation of the proper oceanic deep-water carbonate sediments. The fifth milestone is associated with the Cretaceous period, when oceanic carbonate accumulation sharply increased due to accumulation of planktonic organisms. [ABSTRACT FROM AUTHOR]

Among cressdnaviruses, only the family Circoviridae is recognized to infect vertebrates, while many others have unknown hosts. Detection of virus-to-host horizontal gene transfer is useful for solving such virus–host relationships. Here, we extend this utility to an unusual case of virus-to-virus horizontal transfer, showing multiple ancient captures of cressdnavirus Rep genes by avipoxviruses—large dsDNA pathogens of birds and other saurians. As gene transfers must have occurred during virus coinfections, saurian hosts were implied for the cressdnavirus donor lineage. Surprisingly, phylogenetic analysis revealed that donors were not members of the vertebrate-infecting Circoviridae, instead belonging to a previously unclassified family that we name Draupnirviridae. While draupnirviruses still circulate today, we show that those in the genus Krikovirus infected saurian vertebrates at least 114 Mya, leaving endogenous viral elements inside snake, lizard, and turtle genomes throughout the Cretaceous Period. Endogenous krikovirus elements in some insect genomes and frequent detection in mosquitoes imply that spillover to vertebrates was arthropod mediated, while ancestral draupnirviruses likely infected protists before their emergence in animals. A modern krikovirus sampled from an avipoxvirus-induced lesion shows that their interaction with poxviruses is ongoing. Captured Rep genes in poxvirus genomes often have inactivated catalytic motifs, yet near-total presence across the Avipoxvirus genus, and evidence of both expression and purifying selection on them suggests currently unknown functions. [ABSTRACT FROM AUTHOR]

Processes taking place in subduction zones are highly debated. The Cretaceous volcanic rocks are voluminously distributed along the coastal area of southeastern (SE) China. To elucidate their petrogenesis and relationship with subduction, we use new zircon U-Pb ages and Hf-O isotopes for the representative Cretaceous volcanic sequences in Zhejiang Province, China. According to stratigraphic investigations, zircon U-Pb ages, and Hf-O isotopes, these volcanic rocks can be divided into different groups corresponding to three stages of volcanic activity: the early (Stage 1, 136-129 Ma), middle (Stage 2, 125-115 Ma), and late (Stage 3, 110-94 Ma) stages. Diverse zircon populations (including antecrysts, autocrysts, and xenocrysts) are recognized. Hf-O isotopes of autocrysts suggest different protoliths for the identified three stages of volcanic activity. Xenocrysts show obvious different compositions from autocrysts. Antecrysts share similar compositions with autocrysts, which favor similarities in the magmas from which they were generated. Our observations (very small age intervals between antecrysts and autocrysts, sources for volcanic rocks throughout the entire crust, and volcanic magmatism with long-term and discontinuous characteristics), were inconsistent with the traditional melt-dominated magma chamber model. Consequently, we propose that those volcanic rocks were derived from long-lived transcrustal magmatic systems (TCMS), dominated by crystal mush, instead of melt-dominated magma chambers, maintained and recharged by a discontinuous contribution of contemporaneous underplated mantle-derived magmas, triggered by paleo- Pacific plate subduction. We suggest the different different stages of volcanic activity and corresponding long-lived TCMS were produced by the change of Pacific plate motion beneath SE China during the Cretaceous period. [ABSTRACT FROM AUTHOR]

The Almacık Block is a tectonic sliver formed during the activity of the North Anatolian Fault Zone (NAFZ). It includes two important tectonic zones of the Western Pontides (NW Anatolia): the İstanbul and the Sakarya Zones meet along a suture zone called the Intra-Pontide Suture Zone (IPSZ). The units within the İstanbul Zone are exposed in the eastern part of the Almacık Block, whereas the rocks of the Sakarya Zone are exposed in the west. In the presented study, some of the magmatic rocks have been analysed using the zircon U-Pb method: these rocks have previously been either incorrectly or not dated. The U-Pb results have shown that some of the granitic rocks in the İstanbul Zone, which intruded into the amphibolites of the Intra-Pontide Suture Zone, have a crystallization age of 559–556 Ma. A granitoid block in the Upper Cretaceous wild flysch formed over the units of the İstanbul Zone had an age of ~566 Ma. Two distinct granitoid bodies in the Sakarya Zone were dated at 404.5 ± 3.9 Ma (Early Devonian) and 161.8 ± 0.82 Ma (Late Jurassic) ages. The palaeo-exhumation evolutions of the zones were obtained using the zircon (U-Th)/He technique (ZrHe) to understand the differences in the geological evolution of the individual zones. ZrHe ages of the samples obtained from the İstanbul Zone indicate a pronounced Early Cretaceous palaeo-exhumation period. The Middle-Upper Jurassic Mudurnu Formation in the Sakarya Zone gave ZrHe ages close to its sedimentation age, which indicates that the major part of the unit was not buried too deep to open the ZrHe closure system. Unlike those the İstanbul Zone, the main ZrHe age peaks of the Sakarya Zone are ~202, 160, 98, 74, and 52 Ma. Finally, a sample of the metamorphic rocks that were assigned to the IPSZ yielded a peak age of ~63 Ma, which indicates that the final closure of the Intra-Pontide Ocean (IPO) took place during the Early Tertiary. [ABSTRACT FROM AUTHOR]

Alkaline dikes from the Santos-Rio de Janeiro coast, SE Brazil, mainly from São Sebastião and Búzios islands, yielded a Late Cretaceous paleomagnetic pole (SR) located at 319.7°E 81.2°S (N = 44, A95 = 3.0°, k = 44). This pole includes some sites of alkaline stocks from São Sebastião Island of the same age and supersedes the previous pole for this island. To match the available radiometric ages and the prevailing normal polarity remanence of the rocks with the geomagnetic polarity time scale, the SR pole is placed at 84 Myr. Another group of alkaline rocks, dikes located mainly in Rio de Janeiro, was assigned an age of less than 70 Myr. The ages of the Poços de Caldas, Itatiaia, and Passa Quatro paleomagnetic poles are also discussed based on available radiometric data. Assuming a rigid plate, the SR pole indicates the southward movement of about 7° with virtually no rotation between 100 and 84 Myr. From approximately 84 to 70 Myr, a clockwise rotation of 8° is postulated, with slight variation in latitude. [ABSTRACT FROM AUTHOR]

This study is achieved in the local area of the Eridu oil field, where the Mishrif Formation is considered the main productive reservoir. The Mishrif Formation was deposited during the Cretaceous period in the secondary sedimentary cycle (Cenomanian-Early Turonian as a part of the Wasia Group, a carbonate succession widespread throughout the Arabian Plate. The Mishrif Formation already have been evaluated in terms of depositional environments and their diagenetic processes. Here, it will test the previous conclusions with petrophysical properties delineated by using well logging. The results show there is a fully matching with two reservoir units (MA and MB). Dissolution and primary porosity are responsible for forming a variety of large porosity types. These porosity types have preserved the hydrocarbons in commercial quantities. MA and MB reservoir units show low gamma ray and high to moderate total and effective porosities values. The water saturation Sw in the upper unit (MA) is very high in generally to become water-bearing zone. This appears in all studied wells except in the E-NE part, characterized by patches area of moderate water saturation. In contrast, the lower unit (MB) is characterized by high values of hydrocarbon saturation (Sh) except for some areas in the middle of the studied field. Cap rocks (CR1 and CR2) represents rock unit with low porosity and permeability due to the main components of these units. It contains lime mudstone with log response of this cap rocks indicates high gamma-ray peak value. Compaction and dolomitization are responsible for low porosity and permeability in this type of rock unit. [ABSTRACT FROM AUTHOR]

Complete dinosaur footprint fossils are preserved on the surface of the fluvial and lacustrine sediments of Early Cretaceous Madongshan Formation in Liupanshan area of Ningxia, and the sporopollen is a good carrier to study the paleoclimate information of the time when dinosaurs lived. A systematic sporopollen study was carried out on the fossil occurrence profile of sauropod dinosaur footprints from Cretaceous Madongshan Formation in Qianzhuang village of Longde county, Liupanshan area. A total of 41 genera and 63 species of sporopollen were identified. It is divided into 3 sporopollen assemblages from bottom to top of the profile, including Bisaccates-Jiaohepollis assemblage, Classopollis-Jiaohepollis-Cicatricosisporites assemblage and Cicatricosisporites-Foraminisporis assemblage. The geological age reflected by the characteristics of the sporopollen assemblage is Early Cretaceous Aptian-Albian period. The established vegetation of dinosaurs footprint fossils has undergone a transition from conifers to cypresses, and then to ferns. Further research suggests that the paleoclimate in the age of dinosaurs experiences a change from subtropical subhumid climate to subtropical warm and semi-arid climate, and then to subtropical humid climate. This is consistent with previous research conclusions on sedimentary paleoclimatic environment of Cretaceous Madongshan Formation in Liupanshan area. [ABSTRACT FROM AUTHOR]

The global temperature gradually decreased from the Cretaceous Santonian to Campanian, while angiosperms evolved rapidly and gradually became dominant. The Songliao Basin, NE China, contains abundant fossil palynomorphs from the Santonian to Campanian age. A thorough investigation of fossil palynomorphs in borehole ZKY2-1 of the SW Songliao Basin was performed, reconstructing the vegetation and paleoclimate transition from the Santonian–earliest Campanian (lower Nenjiang Formation) to the late Campanian (Sifangtai Formation). Eighty form-genera from borehole ZKY2-1 have been identified. Three palynomorph assemblages were identified: the Schizaeoisporites–Cyathidites–Inaperturopollenites assemblage, Schizaeoisporites–Classopollis–Retitricolporites assemblage, and Schizaeoisporites–Aquilapollenites–Tricolporopollenits assemblage, from bottom to top. Based on palynological analysis from ZKY2-1 and other boreholes in the Songliao Basin, angiosperm pollen proportion in the Sifangtai Formation is significantly higher than in the lower Nenjiang Formation, indicating rapid angiosperm spread from late Santonian to Campanian. Palynological records indicate relatively humid climate during this period; the content of cool palynological types increased from the lower Nenjiang Formation to the Sifangtai Formation, suggesting a transition from warm to cool climate during the late Santonian–earliest Campanian to the late Campanian. The new palynological evidence from the Songliao Basin reveals a global cooling on land and sea during the late Santonian–Campanian period. This climate change may further promote angiosperm spread during the Late Cretaceous period. [ABSTRACT FROM AUTHOR]

Whether the South China continental margin had shifted from active subduction to passive extension in the Late Cretaceous remains controversial. Located in the northernmost of the South China Sea continental margin, Sanshui Basin developed continuous stratigraphy from Lower Cretaceous to Eocene and provides precious outcrops to study the regional tectonic evolution during the Cretaceous. Therefore, we conducted field observations, petrology, clay mineralogy, geochemistry, and detrital zircon chronology analyses of sedimentary rocks from the Upper Cretaceous Sanshui Formation in Sanshui Basin. Results suggest that the Sanshui Basin is characterized as an intermoutane basin with multiple provenances, strong hydrodynamic environment, and proximal accumulation in the Late Cretaceous. An angular unconformity at the boundary between the Lower and Upper Cretaceous was observed in the basin. The sedimentary facies of the northern basin changed from lacustrine sedimentary environment in the Early Cretaceous to alluvial facies in the Late Cretaceous. The zircon U-Pb ages of granitic gravelly sandstone from Sanshui Formation prominently range from 100 Ma to 300 Ma, which is close to the deposition age of Sanshui Formation. The major and trace elements of the Late Cretaceous sedimentary samples show characteristics of active continental margin, and are different from the Paleogene rifting sequences. Hence, we propose that the northern South China Sea margin underwent an intense tectonic uplift at the turn of the Early and Late Cretaceous (around 100 Ma). Afterward, the northern South China Sea margin entered a wide extension stage in the Late Cretaceous (∼100 to ∼80 Ma). This extensional phase is related to the back-arc extension in the active continental margin environment, which is different from the later passive rifting in the Cenozoic. The transition from active subduction to passive extension in the northern South China Sea may occur between the late Late Cretaceous and the Paleogene. [ABSTRACT FROM AUTHOR]

Botryosphaeriales (Dothideomycetes, Ascomycota) occur in a wide range of habitats as endophytes, saprobes, and pathogens. The order Botryosphaeriales has not been subjected to evaluation since 2019 by Phillips and co-authors using phylogenetic and evolutionary analyses. Subsequently, many studies introduced novel taxa into the order and revised several families separately. In addition, no ancestral character studies have been conducted for this order. Therefore, in this study, we re-evaluated the character evolution and taxonomic placements of Botryosphaeriales species based on ancestral character evolution, divergence time estimation, and phylogenetic relationships, including all the novel taxa that have been introduced so far. Maximum likelihood, maximum parsimony, and Bayesian inference analyses were conducted on a combined LSU and ITS sequence alignment. Ancestral state reconstruction was carried out for conidial colour, septation, and nutritional mode. Divergence times estimates revealed that Botryosphaeriales originated around 109 Mya in the early epoch of the Cretaceous period. All six families in Botryosphaeriales evolved in the late epoch of the Cretaceous period (66–100 Mya), during which Angiosperms also appeared, rapidly diversified and became dominant on land. Families of Botryosphaeriales diversified during the Paleogene and Neogene periods in the Cenozoic era. The order comprises the families Aplosporellaceae, Botryosphaeriaceae, Melanopsaceae, Phyllostictaceae, Planistromellaceae and Saccharataceae. Furthermore, current study assessed two hypotheses; the first one being "All Botryosphaeriales species originated as endophytes and then switched into saprobes when their hosts died or into pathogens when their hosts were under stress"; the second hypothesis states that "There is a link between the conidial colour and nutritional mode in botryosphaerialean taxa". Ancestral state reconstruction and nutritional mode analyses revealed a pathogenic/saprobic nutritional mode as the ancestral character. However, we could not provide strong evidence for the first hypothesis mainly due to the significantly low number of studies reporting the endophytic botryosphaerialean taxa. Results also showed that hyaline and aseptate conidia were ancestral characters in Botryosphaeriales and supported the relationship between conidial pigmentation and the pathogenicity of Botryosphaeriales species. [ABSTRACT FROM AUTHOR]

Climatic variability and silicate weathering are remarkable features throughout the Late Cretaceous period. Late Campanian black shale is considered the most significant silicate source rock in the southern Tethys. Here, we used mineralogical and geochemical data to evaluate the continental weathering intensity and climatic changes as well as their impact on the deposition of the Late Campanian black shale in the Western Desert of Egypt. The studied black shale has a relatively high concentration of Al, Fe, Mg, Ca, Sr, Ga, Co, Cr, and V when compared to the average Post-Archean Australian Shales (PAAS). The studied samples have elevated values of Ga/Rb, and low values of Rb/Sr, Sr/Cu, and K2O/Al2O3, supporting the deposition of Late Campanian shale under warm/humid conditions. Furthermore, the average chemical index of alteration (CIA, 78.6%), chemical index of weathering (CIW; 83.8%), C-value (1.26), Fe/Mn (408), and Mg/Ca (1.54) reveal the predominance of warm/humid climate. The chemical weathering proxies (CIA, CIW, PIA, LnAl2O3/Na2O) and ACNK diagram imply that the Late Campanian samples were exposed to a moderate grade of chemical alteration. The deposition of black shale occurred under high seawater salinity conditions based on Sr/Ba (Avg = 3.6). Additionally, the weathering indices are well correlated with paleoclimatic proxies, suggesting that weathering intensity is strongly affected by paleoclimate. However, chemical weathering during the Late Campanian has a weak influence on oceanic nutrient fluxes. No substantial impact of the paleoclimate during the deposition of Late Campanian black shale on water salinity was reported. [ABSTRACT FROM AUTHOR]

The cause of magmatic tempo in an active plate margin remains controversial, partly due to lack of structural analysis. During 130–105 Ma, the magmatism in the South China Block (SCB) was significantly reduced (lull) and restricted around the Changle‐Nan'ao Belt (CNB) while the magmatism was highly active (flare‐up) in North China. For unveiling the tectonic role on magmatism, a multidisciplinary study including field and microscopic structural observations, magnetic fabric measurement (AMS), and zircon/monazite dating was conducted on the plutons with oriented minerals in the CNB. Structural analysis and AMS results show a highly clustered NE‐striking vertical foliation developed during the emplacement indicating a syn‐emplacement NW‐SE shortening regime. The geochronology results confirm that the emplacement occurred during 130–105 Ma. Regional geologic correlation indicates that the collision between the Dangerous Grounds‐West Philippines Block and SCB was responsible for this shortening regime. The collected depleted zircon εHf(t) data suggest that a possible collision‐triggered slab break‐off caused the syn‐collisional magmatic activity around the CNB. This study shows that the magmatic lull in the SCB was coeval with a crustal shortening regime due to the arrival of a microcontinent carried by the subduction slab, while the magmatic flare‐up was coeval with an extensional regime due to the subduction roll‐back and retreat as evidenced by the Cretaceous evolution of the SCB before and after the collision and that of North China which is unaffected by the collision. The cause of magmatic tempo in the continental margin is largely due to the tectonic evolution of underlain subduction slabs. Plain Language Summary: Magmatic activity is closely connected to human life as it provides us with useful metals, releases greenhouse gases, triggers natural hazards. It is necessary to explore what controls a magmatic activity. Several previous studies considered that a shortening regime with thickened crust causes strong magmatism (flare‐up). The South China Block (SCB) featured by alternating magmatic flare‐up and lulls, provides an appropriate research target to test this hypothesis. During the Cretaceous, the SCB was dominated by an extensional regime caused by the Paleo‐Pacific oceanic slab subduction. However, our structural analyses on the SCB document a shortening regime caused by the collision between the SCB and a microcontinent carried by the Paleo‐Pacific oceanic slab in the period of the Cretaceous. During the collision, the SCB was generally featured by a magmatic lull, although magmatic activity was only observed around the Changle‐Nan'ao Belt, probably caused by the break‐off of the subducted Paleo‐Pacific oceanic slab. Before and after the collision, the extensional regime caused by Paleo‐Pacific oceanic slab subduction was coeval with magmatic flare‐up. This study questions the previous claims and proposes that the tectonic evolution of the subducting slab may control the magmatic flare‐up and lull in the overlain active continental margin. Key Points: The 130–105 Ma syn‐tectonic plutons intruded the Changle‐Nan'ao Belt in a NW‐SE shortening regime caused by a microcontinent collisionThe shortening/extension regimes were coeval with magmatic lull/flare‐up in the East Asia Continental Margin during the CretaceousThe collision causing break‐off can account for the plutonism in the Changle‐Nan'ao Belt during the magmatic lull of the South China Block [ABSTRACT FROM AUTHOR]

The Lower Cretaceous Bayingebi Formation at the Hari sag, Northern China is a significant bearing oil-gas tight reservoir in the Yin'E Basin. In order to understand petrophysical properties of the reservoirs, the diagenesis and hydrocarbon accumulation phases were investigated using casting thin sections, scanning electron microscopy (SEM), X-ray diffraction and fluid inclusion analysis. Additionally, the histories of burial evolution, organic matter thermal evolution and hydrocarbon charge are investigated. The results showed that the pore types include primary pore, intergranular pore and dissolution intragranular pore. The diagenesis of sandstone reservoirs in the process of burial and diagenesis mainly includes compaction, fracture, cementation, metasomatism and dissolution. The comprehensive analysis of various diagenetic stage indexes shows that Bayingebi Formation is in the middle diagenetic stage A-B. The homogenization temperature and salinity of fluid inclusions are low temperature and low salinity (120 °C ∼ 130 °C, 0% ∼ 9%), medium temperature and high salinity (140 °C ∼ 150 °C, 10% ∼ 17%) and high temperature and medium salinity (160 °C ∼ 170 °C, 9% ∼ 11%) respectively. According to the homogenization temperature of the inclusions and the history of burial evolution, the Bayingebi Formation has mainly three phases of hydrocarbon accumulation (100 ∼ 97Ma, 93 ∼ 87Ma, 84 ∼ 81Ma). [ABSTRACT FROM AUTHOR]

Around half of the total carbonate rocks of Romanian territory are Upper Jurassic-Lower Cretaceous age. Most of them are able to develop karst phenomena. In the southern-central part of the Moesian Platform Jurassic-Cretaceous deposits are at 2000-3000 m depth. The existence of the hydrocarbon accumulations in the area was just proved (Talpa, Harlesti, Videle fields). In the calcareous deposits, the seismic profiles and the attributes of seismic traces highlighted some specific geological features: The collapse karst areas, formed in Jurassic-Neocomian deposits. The seismic expression of these areas is one of chaotic reflections zone flanked by converging, strong tilted faults. The paleo-valley systems formed by erosion of the Cretaceous relief, filled with different terms of the Lower Sarmatian (a succession of marls and sands). The reflections configuration is specific to the passing from the valley fill lithology to the Cretaceous calcareous formations of the adjacent areas. The reef build-ups in Upper Jurassic-Lower Cretaceous formations, expressed by chaotic reflection mound zones draped for quasi horizontal superimposed strata. The seismic trace attributes and velocity analyses are important tools in reservoir quality definition, giving information regarding porosity and fluid contents. [ABSTRACT FROM AUTHOR]

Stratospheric water vapor (SWV) variations play an important role in influencing the Earth's energy budget. Here, we investigate the SWV variations in the past 250 million years (Myr) using a fully coupled Earth System Model. It is found that both CO2 concentration and paleogeography have prominent influences on the SWV variations, while solar insolation plays a minor role. The SWV increases with surface warming and stratospheric moistening rate is accelerated during the warm periods in the past 250 Myr except for the Pangea supercontinent stage. The ratio of stratospheric moistening to surface warming is smaller in the warm Pangea supercontinent stage compared to that during the warm Cretaceous Period, which is due to the ascending and consequent cooling of the tropical tropopause layer associated with the severe surface warming over the tropical Pangea supercontinent. Our results suggest that paleogeography is an important factor in regulating SWV variations in deep‐time climate. Plain Language Summary: We study the stratospheric water vapor (SWV) variations in the past 250 million years (Myr) using simulations of a fully coupled Earth System Model. The SWV generally increases with surface warming. It is found that surface warming and SWV increase can reach about 12.4 K and 89.2% in the past 250 Myr, respectively, with respect to the preindustrial condition. Both CO2 concentration and paleogeography have prominent influence on the SWV variations, while solar insolation plays a minor role. Although both the Pangea supercontinent stage and Cretaceous period have similar warm climate states, our results show that the SWV is much less in the Pangea supercontinent stage than that during the Cretaceous period. This discrepancy is found to be caused by different continental configurations. The SWV is primarily controlled by the tropical tropopause temperature. The stronger surface warming over the tropical Pangea supercontinent leads to ascending and thus cooling of the tropical tropopause layer. This work helps to understand the contributions of paleogeography to the SWV variations in the paleoclimate. Key Points: Both CO2 concentration and paleogeography have prominent influence on the Stratospheric water vapor (SWV) variations in the past 250 million yearsThe SWV increases with surface warming and stratospheric moistening rate is accelerated during warm periodsThe ratio of stratospheric moistening to surface warming is sensitive to the continental configurations in warmer climates [ABSTRACT FROM AUTHOR]

Metamorphic core complexes are developed in crustal activity belts at the continental margins or within continents, and their main tectonic feature is that the ductile middle crust is exhumed at the surface. The deformation properties are closely related to the geodynamic process affecting the continental crust. However, the evolution of the metamorphic core complexes after their formation is still unclear. The Cretaceous Liaonan metamorphic core complex developed in the eastern North China craton provides an ideal environment to study its evolution. In this study, we estimate the paleo-temperature and paleo-stress at the time of formation of the metamorphic core complex dynamical recrystallization of quartz and calculate the thermo-rheological structure of the present Liaonan metamorphic core complex by one-dimensional steady-state heat conduction equation and power-creep law. The results show that compared with the Cretaceous period, the geothermal heat flow value of the present Liaonan metamorphic core complex decreases from 70–80 mW/m2 to 49.4 mW/m2, the thermal lithosphere thickness increases from 59–75 km to 173 km, and the brittle transition depth increases from 10–13 km to about 70 km, showing coupling of the crust–mantle rheological structure. We speculate that the evolution of the thermo-rheological structure of the Liaonan metamorphic core complex is possibly caused by rapid heat loss or lithospheric mantle flow in the Bohai Bay Basin. [ABSTRACT FROM AUTHOR]

The Yamama Formation represents a part of the Late Berriasian-Aptian sequence, deposited during the Early Cretaceous period within the main shallow marine depositional environment. The studied area covers three oil fields; Sindbad oil field, Halfaya and Ad'daimah oil field, located in southeastern Iraq. Six major microfacies were recognized in the succession of the studied area represented by the Yamama Formation to determine and recognize depositional paleoenvironments. These microfacies are; Peloidal  Packstone, Algal  Wackestone to Packstone, Bioclastic Wackestone – Packstone, Foraminiferal Bioclastic Wackstone, Packstone, Peloidal – Oolitic Grainstone and Mudstone Microfacies. These microfacies are classified into three standard microfacies and three Facies Zones MFS-18/FZ- 8, SMF 15/FZ-6 and SMF-10/FZ-7, representing the restricted marine, shoal and shallow open marine associations facies, respectively. The Yamama succession in the studied area is divided into three cycles representing three depositional stages of highstand system tracts. These three cycles are characterized by shallowing upward depositional mode where they are deposited in the shallow open marine shoal with semi-restricted associations facies for each cycle. To the northeast of the study area near Halfya-5 well, the shoal association appeared in the lower and middle part of the Yamama succession, and in Da-1 and Sn-2 were three cycles. This case suggests that the paleo high was developed north of the study area, while the open marine was extended to the southern part. The presence of shallow open marine association facies between the Sulaiy and Yamama successions refers to continuous deposition during the same depositional stage in all studied wells. It may mark the end of the Sulaiy succession with the maximum flooding surface (MFS). This first depositional stage is started with the shallow open marine association facies underlain by shoal facies association and then semirestricted association. The repetition of this cycle in the studied sections symmetrically indicates the harmonic oscillation in sea level during the second and third depositional stages of this sequence. The Halfaya oil field within the Mesopotamian Block and Ad'daimah and Sindbad oil fields within the Basra Blok explain the significant variation in the thickness for this succession between the Halfaya oil field and the other oil fields. This may suggest the occurrence of high depositional subsidence in Basra Blok and uplifting during the Yamama depositional stages. The fact that the studied sections are distinguished by the same cycles, albeit roughly, indicates that the lifting and sitdown processes synchronized sedimentation. [ABSTRACT FROM AUTHOR]

The reef lobsters of the family Enoplometopidae de Saint Laurent, 1988 are attractive marine aquarium pets but the generic assignments have been controversial. Molecular phylogeny using five genetic markers (three mitochondrial and two nuclear) on 11 of the 12 species known in the family successfully reconstructed a robust phylogenetic tree for the reef lobsters with two well-supported groups. The genus Hoplometopus Holthuis, 1983 is revived but with diagnostic characters revised and H. voigtmanni (Türkay, 1989) should be treated as a synonym of H. holthuisi (Gordon, 1968). Four synapomorphies are identified in Enoplometopidae, including the number of the intermediate and postcervical teeth on the carapace, the shape of abdominal pleura and the spination of the palm of large chelipeds. Fossil calibration and ancestral range reconstruction analyses suggested that reef lobsters had a Tethyan deeper water origin and emerged during the Cretaceous period. Enoplometopus s.s. was relatively primitive, whereas Hoplometopus diverged in the Central Indo-Pacific in the Upper Cretaceous and later crossed the Mediterranean into the Atlantic. Overall the family Enoplometopidae mainly speciated in the Central Indo-Pacific, and actively re-occupied shallow-water habitats and invaded temperate regions. Multigene molecular phylogenetic analysis on almost all the species in Enoplometopidae has successfully reconstructed a robust evolutionary tree for these attractive reef lobsters. The family should be subdivided into two genera. Reef lobsters originated in the Tethy Sea during the Cretaceous, and speciation mainly occurred in the Central Indo-Pacific, with active re-occupation occurring in shallow-water habitats and invasion of temperate regions. [ABSTRACT FROM AUTHOR]

If you find a bird bone in deposits from the Cretaceous period (145–66 million years ago), chances are it will belong to an enantiornithine bird. This extinct group of birds was mostly arboreal and dominated terrestrial environments from 130 to 66 million years ago. With approximately 90 known genera, they account for more than half of the known diversity of Mesozoic birds. Yet, despite apparently out-competing birds more closely related to living species in most Cretaceous continental environments, enantiornithines mysteriously went extinct at the end of the Cretaceous, alongside all other non-neornithine (crown-bird) dinosaurs. Jingmai O'Connor introduces the enantiornithines, the dominant group of bird in the Cretaceous. [ABSTRACT FROM AUTHOR]