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Crustal deformation and hydrothermal percolation related to the India‐Asia collision have caused extensive remagnetization of the Tethyan Himalaya Terrane (THT). The present work identified three phases of regional remagnetization during 62.3–50.0 Ma for the east‐central THT. Consequently, a model of three‐stage India‐Asia collision was proposed. The east‐central THT first collided with the southward migrated southern margin of the Lhasa Terrane (LT) at 5.4 ± 0.9°N during 62.3–60.9 Ma. Subsequently, the THT continuously moved northward and pushed the southern margin of the LT back to its original position prior to the initiation of fore‐arc and back‐arc extension on both sides of the Gangdese magmatic arc. Since the final suturing of the THT with Asia at ∼10°N during 59.8–58.0 Ma, the east‐central THT remained stationary until India collided with it at 10.9 ± 5.1°N at ∼50.0 Ma. Plain Language Summary: The collision of India and Asia caused intense tectonic deformation and hydrothermal alteration throughout the Tethyan Himalaya Terrane (THT), which resulted in the large‐scale remagnetization in the THT. The regional remagnetization of the THT can be used to constrain the India‐Asia collision process, on the premise that the time of remagnetization can be determined. Based on this assumption, we measured two representative Paleocene remagnetized components from Early Jurassic limestones in the Gyangze Basin in the east‐central THT. These remagnetized components, combined with non‐remagnetized components and remagnetization events recorded in the adjacent areas, suggest that the east‐central THT experienced three phases of regional remagnetization during 62.3–50.0 Ma. The first and second phases of remagnetization in the north‐central part of the east‐central THT occurred at the paleolatitude of 5.4 ± 0.9°N at 62.3–60.9 Ma and 10.3 ± 1.0°N–9.5 ± 1.1°N at 59.8–58.0 Ma, respectively. The third phase of remagnetization occurred in the southern part of the east‐central THT, at the paleolatitude of 10.9 ± 5.1°N at ∼50.0 Ma. Consequently, a model of three‐stage India‐Asia collision and southward spreading tectonic deformation of the THT was proposed based on these successive remagnetizations. Key Points: The east‐central Tethyan Himalaya Terrane (THT) experienced three phases of large‐scale remagnetization during 62.3–50.0 MaThe collision of THT with the Lhasa Terrane commenced at 62.3–60.9 Ma and finished at 59.8–58.5 MaIndia finally collided with the THT at the paleolatitude of ∼10.9 ± 5.1°N at ∼50.0 Ma [ABSTRACT FROM AUTHOR]

The Takestan area is in the western part of the Alborz magmatic arc. Magmatic rocks of the area consist of plutonic rocks (e.g. granitoids), effusive volcanic, and pyroclastic rocks. Using U-Pb zircon LA ICP-MS dating, we conclude that major parts of Takestan plutonic rocks were emplaced at 41–39 Ma (Late Eocene, Bartonian), but a small part of these rocks have ages of ~37 Ma (Late Eocene, Priabonian). The dacitic rocks have an age of ~39 Ma (Late Eocene, Bartonian) and the rhyolitic rocks are the youngest part of the magmatic rocks of the region with ages of 37–35 Ma (Late Eocene, Priabonian). Old zircons are present in all of granitoid and volcanic samples, except for a dacitic sample. They are interpreted both as earlier components in a long-lived magma chamber and inherited zircons from older continental crust. The age of magmatic rocks in the western part of the Alborz magmatic arc decreases from east to west, but the ages of the majority of them are limited to Palaeogene. The studied rocks like other Palaeogene magmatic rocks of Iran were possibly formed in a subduction related tectonic environment. Indeed, the Palaeogene magmatism of Iran is akin to geodynamic events related to Neotethyan subduction beneath Iranian micro-continent at the southern part of Eurasia. [ABSTRACT FROM AUTHOR]

We describe a new species of Ampelopsideae (Vitaceae), Nekemias mucronata sp. nov., from the Rupelian of Cervera (Spain) and revise another fossil species, Ampelopsis hibschii, originally described from Germany. Comparison with extant Ampelopsideae suggests that the North American species Nekemias arborea is most similar to Nekemias mucronata while the East Mediterranean Ampelopsis orientalis is the closest living relative of A. hibschii. Our review of fossil data indicates that, during the Eocene, four species of Ampelopsideae occurred in Eurasia, that is, N. mucronata in the Czech Republic, A. hibschii in Kazakhstan, and two fossil species in the Far East (Ampelopsis cercidifolia and Ampelopsis protoheterophylla). In the Oligocene, a new species, Ampelopsis schischkinii, appeared in Kazakhstan; meanwhile, N. mucronata spread eastwards and southwards, and A. hibschii mainly grew in Central Europe. In the late Oligocene, N. mucronata became a relict in the Iberian Peninsula and Nekemias might have persisted in Western Eurasia until the latest Miocene (“Ampelopsis” abkhasica). The last occurrence of A. hibschii was in the Middle Miocene in Bulgaria, probably a refuge of humid temperate taxa, along with Ampelopsis aff. cordata. Carpological remains suggest that this lineage persisted in Europe at least until the Pleistocene. Our data confirm previous notions of the North Atlantic and Bering land bridges being important dispersal routes for Ampelopsideae. However, such dispersion probably occurred during the Paleogene rather than the Neogene, as previously suggested. A single species of Ampelopsideae, A. orientalis, has survived in Western Eurasia, which appears to have been linked to a biome shift. [ABSTRACT FROM AUTHOR]

Palaeogene South American faunas include enigmatic ungulates that cannot be classified unequivocally within any of the main South American (SA) Native Ungulates clades (Litopterna, Notoungulata, Astrapotheria, Pyrotheria and Xenungulata) because they retain plesiomorphic features, resembling Laurasian ‘archaic ungulates’ traditionally classified within the order ‘Condylarthra’. Most SA ‘condylarths’ are known by partial dental series and isolated teeth and unassociated postcranial remains, hampering comparisons with better-known ungulates. Here, we describe a nearly complete skull and associated mandible of an SA ‘condylarth’, Talquinodus puertai gen. et sp. nov., preserving most of the dentition and basicranium, derived from middle Eocene rocks of the Sarmiento Formation at Central Patagonia. Talquinodus shows a combination of plesiomorphic traits (complete dentition with bunolophodont cheek teeth, ring like ectotympanic, retention of stapedial system, etc.), combined with some autapomorphies, as the reduction of the m3 talonid. Our phylogenetic analyses support consistently that Talquinodus belongs to the SA radiation of Euungulata along with Litopterna, Notoungulata and Astrapotheria. However, the internal relationships could not be resolved unambiguously: Talquinodus could be a didolodontid related to the origin of Litopterna, or could be part of a separate radiation of South American archaic ungulates, along Depaulacoutoia, Lamegoia and Escribania, with no descendants in post-Eocene faunas. [ABSTRACT FROM AUTHOR]

Microfaunal analysis of Cretaceous and Paleogene sediments collected over several decades from Western Siberia has illuminated the diversity, stratigraphic distribution, and paleoecological signifi cance of the rare low trochospiral benthic foraminiferal genus Bagginoides. Here, we describe two new species B. yamalensis n.sp. and B. tibeisalinella n.sp [ABSTRACT FROM AUTHOR]

The aim of this work is to reveal correlation between the spectral characteristics of the open soil surface on the Pleiades image (April 25, 2020) and soils of a key site with a complex soil cover pattern in the south of the Volga Upland (Volga–Don irrigation system, Volgograd oblast). The study area is specified by the lithological heterogeneity: Paleogene and Neogene sands and loams are overlain by a mantle of Quaternary brown loams of variable thickness from 1–2 m to complete thinning out. The soil cover is represented by light chestnut solonetzic complexes complicated by a mosaic of lithological variants and erosion–accumulative combinations. Eight soil groups have been specified, and a map of their distribution has been developed for the key site of 343 ha with the use of digital methods of processing the spectral characteristics of the satellite image and ground-based soil information. Soil groups differ in general features of the soil surface due to differences in the contents of gravel and stones, texture of the surface horizon (from sand to silt loam), occurrence of brightened crusts, and surface effervescence depending on the thickness of the upper lithological layer. Soils with different horizonation of the profile—agrochestnut soils, agrozems, and agrosolonetzes—fall within the same groups of surface spectral characteristics; vice versa, soils of the same genetic type and, sometimes, subtype fall into different groups. This is explained by the incomplete correspondence of the properties of the soil surface affecting the spectral characteristics to the internal structure of the soil profile as a whole. [ABSTRACT FROM AUTHOR]

The predation-driven Mesozoic marine revolution (MMR) is believed to have induced a dramatic change in the bathymetric distribution of many shallow marine invertebrates since the late Mesozoic. For instance, stalked crinoids – isocrinids (Isocrinida) have undergone a striking decline in shallow-sea environments and today they are restricted to deep-sea settings (below 100 m depth). However, the timing and synchronicity of this shift are a matter of debate. A delayed onset of MMR and/or shifts to a retrograde, low-predation community structure during the Paleogene in the Southern Ocean were invoked. In particular, recent data from the Southern Hemisphere suggest that the environmental restriction of isocrinids to the deep-sea settings may have occurred at the end of the Eocene around Antarctica and Australia, and later in the early Miocene in New Zealand. Here, we report the anomalous occurrence of the isocrinids in shallow nearshore marine facies from the middle Miocene of Poland (Northern Hemisphere, Central Paratethys). Thus, globally, this is the youngest record of shallow-sea stalked crinoids. This finding suggests that some relict stalked crinoids may have been able to live in the shallow-water environments by the middle Miocene, and further confirms that the depth restriction of isocrinids to offshore environments was not synchronous on a global scale. [ABSTRACT FROM AUTHOR]

We describe the first fossil species of the extant genus Eulomalus (Coleoptera: Histeridae: Dendrophilinae: Paromalini) from the Eocene Baltic amber. Eulomalus balticussp. nov. has a flattened body shape typical for the Histeridae living under the bark of decaying trees. The newly described species is the only European representative of the genus, which is presently distributed chiefly in the Indomalayan realm. [ABSTRACT FROM AUTHOR]

The Cenozoic topographic development of the Himalaya‐Tibet orogen (HTO) substantially affected the paleoenvironment and biodiversity patterns of High Asia. However, concepts on the evolution and paleoenvironmental history of the HTO differ massively in timing, elevational increase and sequence of surface uplift of the different elements of the orogen. Using target enrichment of a large set of transcriptome‐derived markers, ancestral range estimation and paleoclimatic niche modelling, we assess a recently proposed concept of a warm temperate paleo‐Tibet in Asian spiny frogs of the tribe Paini and reconstruct their historical biogeography. That concept was previously developed in invertebrates. Because of their early evolutionary origin, low dispersal capacity, high degree of local endemism, and strict dependence on temperature and humidity, the cladogenesis of spiny frogs may echo the evolution of the HTO paleoenvironment. We show that diversification of main lineages occurred during the early to Mid‐Miocene, while the evolution of alpine taxa started during the late Miocene/early Pliocene. Our distribution and niche modelling results indicate range shifts and niche stability that may explain the modern disjunct distributions of spiny frogs. They probably maintained their (sub)tropical or (warm)temperate preferences and moved out of the ancestral paleo‐Tibetan area into the Himalaya as the climate shifted, as opposed to adapting in situ. Based on ancestral range estimation, we assume the existence of low‐elevation, climatically suitable corridors across paleo‐Tibet during the Miocene along the Kunlun, Qiangtang and/or Gangdese Shan. Our results contribute to a deeper understanding of the mechanisms and processes of faunal evolution in the HTO. [ABSTRACT FROM AUTHOR]

Complex patterns of genome evolution associated with the end-Cretaceous [Cretaceous-Paleogene (K-Pg)] mass extinction limit our understanding of the early evolutionary history of modern birds. Here, we analyzed patterns of avian molecular evolution and identified distinct macroevolutionary regimes across exons, introns, untranslated regions, and mitochondrial genomes. Bird clades originating near the K-Pg boundary exhibited numerous shifts in the mode of molecular evolution, suggesting a burst of genomic heterogeneity at this point in Earth's history. These inferred shifts in substitution patterns were closely related to evolutionary shifts in developmental mode, adult body mass, and patterns of metabolic scaling. Our results suggest that the end-Cretaceous mass extinction triggered integrated patterns of evolution across avian genomes, physiology, and life history near the dawn of the modern bird radiation. [ABSTRACT FROM AUTHOR]

Here we report on anguimorph lizards from the earliest Eocene (MP 7) of the Dormaal locality in Belgium, from the time of the warmest global climate of the past 66 million years. Several clades can be identified in this site: Glyptosauridae, Varanidae, and Palaeovaranidae. Our study focuses on glyptosaurid specimens previously reported from the site, some of which had been provisionally described as a new species,? Placosaurus ragei , and some assigned to an unnamed Placosauriops -like 'melanosaurine'. Our study presents data on new material, including an almost complete glyptosaurine frontal that has enabled us to assign much of the previously described material to a single genus and species. The specimens that had been assigned to both ? P ragei and the 'melanosaurine' share apomorphies (flat osteoderms and chevron-shaped osteoderms) with Gaultia , a glyptosaurid previously known from the earliest Eocene of Wyoming, USA. The Dormaal material represents the first record of this genus outside North America. In fact, the only potential evidence of the occurrence of 'Melanosaurinae' in Dormaal might be a single isolated vertebra described here. Here we also describe previously unfigured material of Saniwa and palaeovaranids from Dormaal. The presence of previously reported helodermatids cannot be supported in this Belgian site. [ABSTRACT FROM AUTHOR]

We report the discovery of an ancient forest bed near Stanley, on the Falkland Islands, the second such ancient deposit identified on the South Atlantic island archipelago that is today marked by the absence of native tree species. Fossil pollen, spores and wood fragments preserved in this buried deposit at Tussac House show that the source vegetation was characterized by a floristically diverse rainforest dominated by Nothofagus -Podocarpaceae communities, similar to cool temperate Nothofagus forests/woodlands and Magellanic evergreen Nothofagus rainforests. The age limit of the deposit is inferred from the stratigraphic distribution of fossil pollen species transported by wind, birds or ocean currents from southern Patagonia, as well as similar vegetation types observed across the broader region. The deposit is suggested to be between Late Oligocene and Early Miocene, making it slightly older than the previously analysed Neogene West Point Island forest bed (200 km west of Tussac House). The combined evidence adds to our current knowledge of the role of climate change and transoceanic dispersal of plant propagules in shaping high-latitude ecosystems in the Southern Hemisphere during the late Palaeogene and Neogene. [ABSTRACT FROM AUTHOR]

To explore both environmental change and the response of non‐fossilizing phytoplankton across the Cretaceous‐Paleogene (K‐Pg) boundary mass extinction event, we determined changes in organic matter (OM) sources using a range of apolar (n‐alkanes, acyclic isoprenoids, steranes, and hopanes) and polar (BIT index) biomarkers. We analyzed two K‐Pg proximal sections, located in the Mississippi Embayment, Gulf Coastal Plain (USA), covering ∼300 kyrs prior to and ∼3 myrs after the K‐Pg event. The OM abundance and composition changed dramatically across the boundary. The post‐impact ejecta layer and burrowed unit are characterized by an increase in the mass accumulation rate (MAR) of plant and soil biomarkers, including high‐molecular‐weight n‐alkanes and C29 steranes as well as the BIT index, related to an erosive period which transported terrestrial OM to the ocean in the aftermath of the impact event. At the same time, MARs of putative aquatic biomarkers decrease (low‐molecular‐weight n‐alkanes, C27 steranes and pristane and phytane), which suggests a collapse of the marine phytoplankton community. The increase of terrestrial OM to the ocean, during the first 280 kyrs after the Chicxulub impact event, is a combination of reworked kerogen, soil and some plant material. Crucially, within the latter part of this erosion period, only ∼160 kyrs after the K‐Pg do biomarkers return to distributions similar to those in the upper Cretaceous, although not to pre‐impact MARs. Thus, our results suggest a long‐term interval for the full sedimentary and ecological recovery of the non‐fossilizing phytoplankton community after this event. Plain Language Summary: The Cretaceous‐Paleogene (K‐Pg) boundary coincides with the latest of the five major mass extinctions in Earth's history. Determining the nature of the associated rapid environmental change and biotic recovery is critical for knowing the cause and effects of this key event and contributes to our understanding of the ongoing biodiversity crisis. We analyzed biomarkers (molecular fossils) in two K‐Pg sections in the Gulf Coastal Plain (USA) near the impact site, covering ∼300,000 years prior to, and ∼3,000,000 years after the K‐Pg event. The organic matter (OM) abundance and composition changed dramatically after the impact event. In particular, an increase in the concentration of plant and soil biomarkers occurred in the first 280,000 years after the impact and is attributed to an erosive period which transported OM from the land to the ocean. At the same time, the concentrations of marine algal biomarkers decrease, suggesting a collapse of the marine algal community. About 160,000 after the K‐Pg event, marine biomarkers return to distributions similar to those pre‐impact. This suggests an initial recovery of algal communities on the Gulf Coastal Plain, although they never recover to pre‐impact abundances during the studied interval (∼3,000,000 after impact). Key Points: Intense erosive regime after the K‐Pg boundary, coincident with collapse of the marine phytoplankton community on the Gulf Coastal PlainInitial recovery of non‐fossilizing algal communities started ∼160 kyr after the K‐Pg event although with lower mass accumulation rates than pre‐impactSedimentary conditions never return to their pre‐impact state, suggesting a long‐term perturbation to the system [ABSTRACT FROM AUTHOR]

Despite making up one of the most ecologically diverse groups of living birds, comprising soaring, diving and giant flightless taxa, the evolutionary relationships and ecological evolution of Anseriformes (waterfowl) remain unresolved. Although Anseriformes have a comparatively rich, global Cretaceous and Paleogene fossil record, morphological datasets for this group that include extinct taxa report conflicting relationships for all known extinct taxa. Correct placement of extinct taxa is necessary to understand whether ancestral anseriform feeding ecology was more terrestrial or one of a set of diverse aquatic ecologies and to better understand avian evolution around the K-T boundary. Here, we present a new morphological dataset for Anseriformes that includes more extant and extinct taxa than any previous anseriform-focused dataset and describe a new anseriform species from the early Eocene Green River Formation of North America. The new taxon has a mediolaterally narrow bill which is rarely found in previously described anseriform fossils. The matrix created to assess the placement of this taxon comprises 41 taxa and 719 discrete morphological characters describing skeletal morphology, musculature, syringeal morphology, ecology, and behavior. We additionally combine the morphological dataset with published sequences using Bayesian methods and perform ancestral state reconstruction for select morphological, ecological and behavioral characters. We recover the new Eocene taxon as the sister taxon to (Anseranatidae+Anatidae) across all analyses, and find that the new taxon represents a novel ecology within known Anseriformes and the Green River taxa. Results provide insight into avian evolution during and following the K-Pg mass extinction and indicate that Anseriformes were likely ancestrally aquatic herbivores with rhamphothecal lamellae.. [ABSTRACT FROM AUTHOR]

The Paleogene-Neogene strata in the Western Depression of the Qaidam Basin represent a primary focus for oil and gas exploration and development. Influenced by both terrigenous clastic influx and endogenic carbonate deposition, these strata exhibit significant variation in sedimentary systems and reservoir characteristics. This study comprehensively examines the depositional patterns and reservoir properties of the Paleogene-Neogene sequence across the inner, middle, and outer belts of the basin, employing core analysis, thin section petrography, and physical property assessment of reservoirs. Key findings include 1) The development of a concentric sedimentary system in the Western Depression during the Paleogene-Neogene period, characterized by increased carbonate mineral content and decreased clastic material from the periphery to the center of the basin. 2) Varied sedimentary facies associations across different zones, with the outer belt dominated by fan delta and braided river delta deposits, and the middle and inner belts characterized by near- shore shallow lacustrine carbonates and algal mat deposits, and offshore semi-to deep-lacustrine fine sediments, respectively. 3) The outer belt exhibits reservoirs with favorable physical properties and connectivity, while the inner and middle belts show high heterogeneity, indicating potential for lithological traps and shale oil exploration. These insights offer scientific guidance for further investigation into the depositional systems of lacustrine basins in the Western Depression of the Qaidam Basin and for identifying promising reservoirs. [ABSTRACT FROM AUTHOR]

Anomaluroid rodents (i.e. Anomaluridae + Zenkerellidae) have a long evolutionary history in Africa dating back to at least the middle Eocene, but Palaeogene fossil members of the anomaluroid crown group have never been found south of the Sahara. Here, we describe the oldest crown anomaluroid from sub-Saharan Africa, Eliwourus topernawiensis (new genus and species) from the early Oligocene Topernawi Formation of northern Kenya. Bayesian phylogenetic tip-dating analysis of a combined molecular-morphological dataset places ~29.5 Ma Eliwourus as an advanced stem anomalurid, and suggests that crown Anomaluridae originated ~28.2 Ma. The gliding behaviour seen in all crown anomalurids had, therefore, likely evolved before the close of the early Oligocene. Bayesian geocoordinates analysis places the origin of crown Anomaluroidea (~47.2 Ma) in northern Africa, and identifies a stem anomalurid dispersal into equatorial eastern Africa in the latest Eocene or earliest Oligocene. We present the first quantitative analysis of the pace of anomaluroid dental evolution and confirm a remarkably slow or bradytelic rate of phenotypic change, despite significant transformations in postcranial morphology related to the evolution of gliding behaviour during the same interval. The Topernawi area was evidently sufficiently forested during the early Oligocene to support both arboreal rodents and primates. [ABSTRACT FROM AUTHOR]

This study aims to assess the petrophysical characteristics of the reservoirs in the Fana Field of the Paleogene Sokor_1 system of the Termit Basin and generate a 3D static model of the field. This study integrated all the available data, well logs from four exploratory wells, and a 3D seismic section. The five hydrocarbon-bearing units (E_1, E_2, E_3, E_4, and E_5) have been identified. The average petrophysical values of the reservoir in the Paleogene Sokor-1 revealed that E_1 is the best reservoir with low water saturation, good porosity, and excellent permeability. The delineated net-pay thickness of the reservoirs (19.82m, 37.88 m, 55.27 m, 15.26 m, and 23.78 m) was respectively estimated. The effective porosity of the reservoirs was identified to be 20.66 %, 18.79 %, 18.33 %, and 13.15 %. The permeability of the reservoirs (1774.86 mD, 1535.82 mD, 1300.09 mD, 1325.42 mD, and 1339.66 mD respectively) was identified. The water saturation is 28.63 %, 43.70 %, 50.34 %, 61.34 %, and 69.48 % respectively. Stratigraphically, the shale thickness below and above each reservoir can also act as seals for trapping the hydrocarbon accumulation. The seismic interpreted faults trend NW-SW and NNW-SSE. This study showed that the Paleogene Sokor_1 Formation in Termit Basin is an exceptionally promising reservoir with strong indications of significant hydrocarbon-bearing zones. [ABSTRACT FROM AUTHOR]

We report a tarsometatarsus and an associated pedal phalanx from the lower Eocene London Clay of Walton-on-the-Naze (Essex, UK). The specimen resembles the tarsometatarsus of the taxon Limnofregata (Fregatidae), but it belongs to a species that is distinctly larger than any other, extinct or extant, frigatebird, from which it also differs in some morphological features. Because of a close stratigraphical and geographical provenance, as well as a similar large size and frigatebird-like morphology, we consider it possible that the fossil belongs to Marinavis longirostris. This large seabird was initially described from the London Clay of Abbey Wood and is based on fragments of the rostrum, which likewise show a resemblance to the Fregatidae. If correctly assigned to the Fregatidae, the fossils would be among the earliest records of frigatebirds and the first fossils of this group of birds from the Paleogene of Europe, but we note that our tentative classification is still afflicted with considerable uncertainty. [ABSTRACT FROM AUTHOR]

Herein, we present a diverse record of dinoflagellate cysts from the lignite-associated sedimentary succession (belonging to the Akli Formation) at Sonari Lignite Mine, Barmer Basin, Rajasthan State, western India. The dinoflagellate cyst assemblage implies a Danian to Ypresian age for the investigated succession and argues that the deposition of lignitic sequences along India's western margin is not coeval. We also identify two vertebrate (dominantly fish-yielding) units within the studied Akli Formation succession. The Ypresian fish genera (mainly represented by dental remains) include Ginglymostoma, Jaekelotodus, Brachycarcharias, Pycnodus and Myliobatis while the Selandian-Thanetian fish dental remains include Dasyatis. A discontinuous distribution of fish fauna during the early Paleogene (based on the temporal and spatial data) within the lignite-associated sedimentary successions of western and north India allows us to infer the prevalence of separated realms with variably restricted palaeoenvironmental conditions. Overall, the faunal evidence is indicative of dominantly estuarine to shallow marine conditions with enhanced freshwater influence during the Thanetian as compared to the Danian. Our study also argues in favour of the earliest appearance of dinoflagellate cyst Apectodinium in the near-equatorial region of the Tethys Ocean during the early Paleocene. (within Danian). [ABSTRACT FROM AUTHOR]

One new extinct species of the genus Atomaria Stephens, 1829 is described and illustrated: A. (Anchicera) telnovi sp. nov. from Rovno amber. It is the sixth species of the subgenus Anchicera in Eocene amber; two-thirds of all species and two-thirds of all reported Eocene amber silken fungus beetle specimens belong to this subgenus. The reasons for the relative abundance of Anchicera in the Eocene fossil resins are discussed. A key to extinct Eocene species of Atomaria is provided. [ABSTRACT FROM AUTHOR]

The Cenozoic stratigraphy of the Zagros records the ongoing collision between the Arabian and Eurasian Plates and the closure of NeoTethys. A Paleogene NW‐SE trending foreland basin was inherited from a Late Cretaceous precursor. Widespread progradation into the foredeep was a feature of both margins which, allied to ongoing tectonism, had by the late Eocene led to the narrowing and subsequent division of the foredeep into the Lurestan – Khuzestan and Lengeh Troughs, separated by the northward continuation of the rejuvenated Qatar‐Fars Arch. This sub‐division strongly influenced subsequent deposition and the petroleum geology of the area. In addition, the diachronous nature of the Arabian – Eurasian collision led to strong diachroneity in lithostratigraphic units along the length of the Zagros. Hence its petroleum geology is best understood within a regional sequence stratigraphic framework. This study identifies three tectono‐megasequences (TMS 10, TMS 11a, TMS 11b) and multiple depositional sequences. The Cenozoic contains a world class hydrocarbon province with prolific oil reservoirs in the Oligo‐Miocene Asmari Formation sealed by the evaporite‐dominated Gachsaran Formation, mostly contained within giant NW‐SE trending "whaleback" anticlines concentrated in the Dezful Embayment. Reservoirs in the SW are dominantly siliciclastic or comprise mixed siliciclastics and carbonates, whereas those to the east and NE are dominated by fractured carbonates. There remains untested potential in stratigraphic traps, especially in deeperwater sandstone reservoirs deposited along the SW margin of the foredeep. Late Miocene to Pliocene charge to the Asmari reservoirs was mostly from Aptian – Albian Kazhdumi Formation source rocks. In some fields, an additional component was from organic‐rich late Eocene to earliest Oligocene Pabdeh Formation source rocks confined to the narrowing Lurestan – Khuzestan Trough. Where mature, the latter source rock is also a potential unconventional reservoir target, although the prospective area is limited due to recent uplift and erosion. Deeper Jurassic source rocks contributed to the Cheshmeh Khush field in Dezful North. Silurian source rocks charged gas‐bearing structures in the Bandar Abbas region. [ABSTRACT FROM AUTHOR]

An organic geochemical, petrographical, and palynological evaluation was conducted on 30 claystone outcrop samples of the Toraja Formation, along with a geochemical analysis of an oil seep in the Enrekang Sub-basin. The aim of the study was to determine the correlation between oil and source rock in terms of age, depositional environment, organic material sources, and maturity level. The total organic carbon content of the claystone samples varies from 0.03 to 4.52 wt%, which are classified as poor to excellent. The claystones are immature to post-mature with a mixture of Type II and III kerogen. Their vitrinite reflectance values range from 0.47 to 4.52 %Ro. The samples of Toraja Formation rock and the oil seep source rock might have a similar depositional environment, a deltaic marine depositional setting with high oxidizing conditions. Organic material sources for rock and oil samples are dominated by terrestrial input. The oil is inferred to have originated from the Paleogene source rocks, which correlates in age with the Toraja Formation. The recovered palynomorphs from the studied rock samples suggest a late Eocene to Oligocene age with a strong terrestrial influence of shallow marine depositional setting. The biomarker analysis shows that the rock samples have a more substantial contribution from the terrigenous higher plants, while the oil sample indicates a higher degree of marine influence. The maturity levels are also different between the oil (peak mature) and the analyzed rock samples (immature). It is inferred that the oil seep source rock is equivalent to the analyzed rock sample but more mature, having been deposited under more marine conditions. The oil seep source rock is not exposed and is located in the deeper part of the basin. A deeper marine facies (i.e. distal delta front and prodelta facies) in front of the distributary mouth bar within a delta is interpreted as the source rock of the oil seep sample. [ABSTRACT FROM AUTHOR]

The northward subduction of the Neo-Tethys oceanic crust triggered multiple magmatic activities in the West Myanmar Arc, which in turn influenced the deposition of sedimentary pyroclastic rocks from the Cretaceous to Eocene strata in the Central Myanmar Basin (CMB). The pore structure of these lithologic reservoirs is complex and rich in tuffaceous sandstone, which plays an adverse role in reservoir development in this region. To understand the development characteristics and genetic mechanism of the pyroclastic rocks within three sets of reservoirs in this area, a comprehensive analysis was conducted through borehole core observations, thin section identification, scanning electron microscope analysis, and mercury injection tests. The tuffaceous sandstone from the upper Cretaceous to the Eocene is dominated by intermediate-acid volcanic rock debris. The pyroclastic rocks exhibit evident chloritization and ironization, with residual intergranular pores being the principal type accompanied by a smaller amount of intergranular dissolved pores and intragranular dissolved pores. The highest porosity is observed in the Eocene tuffaceous sandstone, ranging from 8% to 12%. The Late Cretaceous to Paleocene sandstones exhibit lower porosity levels of only 4%–6%. These reservoirs are characterized by their low-porosity and low-permeability. Despite the presence of a good source rock in this area, the volcanic debris particles filling the pores, as well as their subsequent devitrification, chloritization, and limonite mineralization, result in pore throat blockage and narrowing. The reservoirs in this area are small in size, exhibit poor reservoir connectivity and lateral continuity, and fail to meet the necessary conditions for commercial-scale hydrocarbon accumulation and migration. [ABSTRACT FROM AUTHOR]

Subtropical evergreen broad‐leaved forest (EBLF) is the predominant vegetation type in eastern China. However, the majority of the region it covers in eastern China was an arid area during the Paleogene. The temporal history and essential factors involved in the evolution of subtropical EBLFs in eastern China remain enigmatic. Here we report on the niche evolution of Quercus section Cyclobalanopsis, which appeared in south China and Japan during the Eocene and became a dominant component of subtropical EBLFs since the Miocene in eastern Asia, using integrative analysis of occurrences, climate data and a dated phylogeny of 35 species in Cyclobalanopsis. Species within clades Cyclobalanoides, Lamellosa, and Helferiana mainly exist in the Himalaya–Hengduan region, adapting to a plateau climate, while species within the other clades mainly live in eastern China under the control of the East Asian monsoon. Reconstructed history showed that significant divergence of climatic tolerance in Cyclobalanopsis began around 19 million years ago (Ma) in the early Miocene. Simultaneously, disparities in precipitation of wettest/warmest quarter and annual precipitation were markedly enhanced in Cyclobalanopsis, especially in the recent eastern clades. During the Miocene, the marked radiation of Cyclobalanopsis and many other dominant taxa of subtropical EBLFs strongly suggest the rapid formation and expansion of subtropical EBLFs in eastern China. Our research highlights that the intensification of the East Asian monsoon and subsequent occupation of new niches by the ancient clades already present in the south may have jointly promoted the formation of subtropical EBLFs in eastern China since the early Miocene. [ABSTRACT FROM AUTHOR]

Menispermaceae are an angiosperm family of mostly climbing plants distributed throughout tropical regions. The fruits in this family have a strong sclerified endocarp and can be used for reliable species‐level identifications, even in a fossilized form. New Paleocene‐age menispermaceous endocarps have recently been discovered in South America and Asia, while in Europe, they are mostly found in the Eocene. This paper focuses on the study of fossil endocarps belonging to Menispermaceae, found in the Petit‐Pâtis locality, which is one of the few Paleocene localities in Europe. The locality is dated to the late Paleocene (57–56 Ma) and the fossils represent flora and fauna in the Paris Basin before the onset of the Paleocene–Eocene Thermal Maximum. Lignitized fossils were photographed and their morphology was analyzed using computed tomography, scanning electron microscope, and geometric morphometric analysis. The analysis of 36 fossils belonging to Menispermaceae revealed that three genera (Stephania, Palaeosinomenium, Tinospora) were present in the late Paleocene of Paris Basin. Differences in internal morphology and a more inflated endocarp base led to a description of a new fossil species—Palaeosinomenium oisensis sp. nov. The occurrence of these genera in the Paleocene of France is consistent with the suggestion that megathermal flora was present in the Paris Basin before the Paleocene–Eocene Thermal Maximum. These three genera are currently the oldest occurrences in Europe, highlighting the connection between paleofloras of the Americas, Europe, and Asia in the Paleocene. [ABSTRACT FROM AUTHOR]

Boninites (BONs), high-Mg andesites (HMAs), and related lavas and dikes of Palaeogene ophiolites of the SW Pacific in Papua, New Guinea, New Caledonia, and the North Island, New Zealand, interpreted as having formed subsequent to forearc basalt (FAB) during subduction initiation (SI) are investigated to determine whether these are similar to second-stage lavas and dikes of other SI ophiolites and the IBM forearc. SW Pacific second-stage lavas and dikes are mostly high-Si BONs, but range to HMAs with the latter appearing to have preceded the formation of the former. Partial melting was due to flux-melting of a depleted source with the addition of hydrous and LREE-, Sr-, and Zr-enriched sediment melts to the mantle wedge subsequent to extraction of first-formed FAB. New Caledonia second-stage BONs are mostly consistent with ~5–15% partial melting of a source, which had undergone two previous melt extraction events and in New Zealand, second-stage HMA dikes are consistent as the result of 10–20% partial melting of a depleted source having undergone initial FAB extraction followed by a maximum of ~25% partial melting of a source produced subsequent to the first extraction event. Thermobarometry calculations of primitive second-stage BON and HMA lavas and dikes record potential temperatures generally similar to but pressures lower than MORB. Although most PUB ophiolite and both New Zealand HMA samples plot within the field of MORB with TP of about 1280–1350°C and pressures of ~0.8–1.80 GPa, all remaining second-stage BONs and HMA exhibit TP and pressures lower than MORB. A clear demarcation exists between New Caledonia BONs and PUB HMA, the latter of which records much higher TP and lower pressures than the former and range from ~1330 to 1420°C and from 0.7 to 1.40 GPa. These anomalously high temperatures for the PUB may infer a plume-induced SI event. [ABSTRACT FROM AUTHOR]

The rhythmic evaporation cycle is an ideal recorder of astronomical cycle signals, but studies on cyclostratigraphy have yet to be directly conducted on halite-rich strata. The Qianjiang Depression of the Jianghan Basin is a representative Eocene East Asian halite-rich basin, and the salt rhythmites that developed therein are important recorders of climate evolution in East Asia. This study selected five wells for basin-scale cyclostratigraphy analysis, taking the Lower Qian 4 member of the Qianjiang Formation as the research object. This study found that the basinal salt lake facies were dominated by obliquity cycles, whereas the shallow-water deposits mainly recorded short eccentricity cycles. The study also found that s3-s6 obliquity cycles could be detected throughout the salt lake sedimentary record. Therefore, a stepwise astronomical tuning scheme was adopted. First, the target intervals in different sedimentary areas were preliminarily tuned to s3-s6 obliquity cycles, and stratigraphic correlation was performed. Then, the tuned data were further adjusted using obliquity cycles to reveal the impact of obliquity on the development of salt rhythmites and establish a floating astronomical time scale (ATS). Sedimentary noise models and pollen analysis further demonstrated that obliquity amplitude modulation cycles drove periodic changes in hydrology and climate. Based on the spatiotemporal distribution of salt rhyth-mite-rich strata in Paleogene East Asia, this study proposes that the development of rhythmic evaporites can reveal the existence of a monsoon-like climate. Astronomical influence was an important driving force for developing the middle Eocene East Asian monsoon. [ABSTRACT FROM AUTHOR]

The post-collisional evolution of the Tibetan lithosphere is of paramount significance to our understanding of collisional orogeny. It is generally postulated that the Lhasa lithospheric mantle was horizontally shortened and thickened coherently with the overlying crust to form a physical barrier, preventing Indian subduction beneath Tibet until the thickened mantle root was foundered during the Miocene. This study first identifies post-collisional oceanic-island basalt (OIB)-type magmatism in the Lhasa Block (LB), as attested by zircon U-Pb age (ca. 58 Ma) and geochemistry--positive Nb-Ta anomalies, high La/Yb, and depleted bulkrock Sr-Nd and zircon Hf isotopes, of diabase in the northern (inboard relative to Indus Suture) part of this block. Coupled with extensive early Paleogene arc-type magmatism in the southern-central LB and thermodynamic modeling, we suggest that these diabases were formed by partially molten upwelling asthenosphere near the base of continental crust, where much of the underlying lithospheric mantle had been removed due to Neo-Tethyan slab rollback and lithospheric delamination. Compared to OIB-type magmatism worldwide, the diabases investigated here were emplaced peculiarly in a region where the continental crust was under horizontal compression and shortening by coeval thrusting. Our study thus implies a decoupled deformation between the crust and mantle of the LB during the early Indian-Asian collision. [ABSTRACT FROM AUTHOR]

For sedinentary archives to be used as a record of hinterland evolution, the factors affecting the archive nust be known. In addition to tectonics, a nunber of factors, such as changes in clinate and paleodrainage, as well as the degree of diagenesis, influence basin sedinents. The Indus River delta-fan systen of South-Central Asia records a history of Hinalayan evolution, and both the onshore and offshore sedinentary repositories have been studied extensively to research orogenesis. However, a nunber of unknowns renain regarding this systen. This paper seeks to elucidate the paleodrainage of the Indus River, in particular when it took on its nodern drainage configuration with respect to conjoinnent of the nain Hinalayan (Punjabi) tributary systen with the Indus trunk river. We leverage the fact that the Punjabi tributary systen has a significantly different provenance signature than the nain trunk Indus River, draining nainly the Indian plate. Therefore, after the Punjabi tributary systen joined the Indus River, the proportion of Indian plate naterial in the repositories downstrean of the confluence should have been higher than in the upstrean repository. We conpared bulk Sr-Nd data and detrital zircon U-Pb data fron the Cenozoic upstrean peripheral foreland basin and downstrean Indus delta and Indus Fan repositories. We deternined that throughout Neogene tines, repositories below the confluence had a higher proportion of naterial fron the Indian plate than those above the confluence. Therefore, we conclude that the Indus River took on its current configuration, with the Punjabi tributary systen draining into the Indus trunk river in the Paleogene, early in the history of the orogen. The exact tine when the tributary systen joined the Indus should correlate with a shift to nore Indian plate input in the down-strean repositories only. While the upstrean repository records no change in Indian plate input fron Eocene to Neogene tines, a shift to increased naterial fron the Indian plate occurs at the Eocene-Oligocene boundary in the delta, but sonetine between 50 Ma and 40 Ma in the fan. Though further work is required to understand the discrepancy between the two downstrean repositories, we can conclude that the tributary systen joined the Indus trunk river at or before the start of the Oligocene. [ABSTRACT FROM AUTHOR]

To uncover the reservoir characteristics and enrichment law of coal-measure gas in Julu sag, Hebei Province, and achieve co-exploration and co-mining, it is necessary to conduct a comprehensive analysis. In this study, we investigated the characteristics of coal-measure gas accumulation in the Taiyuan Formation and Shanxi Formation in the Julu area. This was achieved by collecting data on coal-measure source rocks and organic geochemistry, which were then combined with regional geological conditions. This study indicates that the coal seams and shales of Shanxi Formation and Taiyuan Formation in the study area serve as the primary source rocks. The predominant macerals found in coal rock are vitrinite. Furthermore, the organic matter type present in shale is primarily categorized as type II2, with the organic matter maturity falling within the immature–mature stage. Based on the simulation results of tectonic-burial history, thermal evolution history, and hydrocarbon generation history in the study area, it is evident that the coal-measure source rocks experienced their first peak of hydrocarbon generation during the Mesozoic era as a result of deep metamorphism. Subsequently, the area experienced uplift and erosion, leading to the release of coal-bearing natural gas. Since the Paleogene period, the coal-bearing source rocks have undergone sedimentary burial and entered the secondary hydrocarbon generation stage, resulting in significant production of oil and gas. Based on the analysis of gas content, buried depth, source rock thickness, and sealing conditions in the study area, it is evident that the potential of coal-measure gas resources in the study area is primarily comprised of shale gas with supplementary coalbed methane. It can be inferred that the deeper areas within the study area hold greater exploration prospects. [ABSTRACT FROM AUTHOR]

Drawing on Alain Badiou’s Being and Event, this article develops a philosophical analysis of the Chicxulub Impact Event and the subsequent Cretaceous-Paleogene (K-Pg) mass extinction. Traditional scientific interpretations of these events tend to focus on ideas of natural selection, arguing that the asteroid strike was merely an accelerant for the inevitable decline of the non-avian dinosaurs. More contemporary interpretations seek the deeper causes of the asteroid strike itself, tracing its cosmic origins to the Oort Cloud, the collection of planetesimals that resides at the periphery of the Solar System. This article argues that Badiou’s philosophical representation of situations, multiples, and events elucidates the ontological implications of each of these interpretations. In particular, reading the traditional interpretation in relation to Being and Event highlights its anthropocentric implications, whereas a Badiouan reading of the more contemporary interpretation emphasizes not only humanity’s but also the earth’s nondescript status within the Solar System. In developing this analysis, the article reworks Badiou’s assumption that events (as he understands them) do not occur in the natural world. I argue that, in actuality, the Chicxulub Impact Event captures, in retrospect, Badiou’s understanding of an event as the sudden presentation of that which is unrepresented in a situation. [ABSTRACT FROM AUTHOR]

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Spores, conidiophores, and hyphae of fossil fungi recovered from nine outcropping siltstone and shale samples belonging to the Troncoso, Salto del Macho, and Río Foyel formations in the El Foyel Group at the Río Foyel Section, are described and illustrated. Representatives of 16 genera were recognized. Among the 26 species described, one is proposed as a new species, Inapertisporites lacrimaformis. Amerospores are the most abundant type of spores recovered. Based on the palynostratigraphical analysis of the non-pollinic (fungal) remains, a Paleogene age for the El Foyel Group is suggested. Of the three formations, Troncoso shows the highest abundance and diversity of fungal remains, which is believed to be representative of a period of optimal climatic conditions characterized as warm temperate and humid, probably related to the Middle Eocene Climate Optimum (MECO). Based on the paleoeological preferences of the specimens recovered from the El Foyel Group, a riparian or lacustrine environment in a woodland setting is inferred.

Palaeontologists have long sought to explain the diversification of individual clades to whole biotas at global scales. Advances in our understanding of the spatial distribution of the fossil record through geological time, however, has demonstrated that global trends in biodiversity were a mosaic of regionally heterogeneous diversification processes. Drivers of diversification must presumably have also displayed regional variation to produce the spatial disparities observed in past taxonomic richness. Here, we analyse the fossil record of ammonoids, pelagic shelled cephalopods, through the Late Cretaceous, characterised by some palaeontologists as an interval of biotic decline prior to their total extinction at the Cretaceous-Paleogene boundary. We regionally subdivide this record to eliminate the impacts of spatial sampling biases and infer regional origination and extinction rates corrected for temporal sampling biases using Bayesian methods. We then model these rates using biotic and abiotic drivers commonly inferred to influence diversification. Ammonoid diversification dynamics and responses to this common set of diversity drivers were regionally heterogeneous, do not support ecological decline, and demonstrate that their global diversification signal is influenced by spatial disparities in sampling effort. These results call into question the feasibility of seeking drivers of diversity at global scales in the fossil record. Global trends in biodiversity are subject to regionally heterogeneous diversification processes. Here, the authors examine Late Cretaceous ammonoids, modelling the impact of sampling bias and potential biotic and abiotic drivers on our understanding of their biodiversity trends towards the Cretaceous-Paleogene boundary. [ABSTRACT FROM AUTHOR]

Despite the worldwide distribution and rich diversity of the superfamily Tenebrionoidea, the knowledge of the mitochondrial genomes (mtgenome) characteristics of the superfamily is still very limited, and its phylogenetics and evolution remain unresolved. In the present study, we newly sequenced mtgenomes from 19 species belonging to Tenebrionoidea, and a total of 90 mitochondrial genomes from 16 families of Tenebrionoidea were used for phylogenetic analysis. There exist 37 genes for all 82 species of complete mtgenomes of 16 families investigated, and their characteristics are identical as reported mtgenomes of other Tenebrionoids. The Ka/Ks analysis suggests that all 13 PCGs have undergone a strong purifying selection. The phylogenetic analysis suggests the monophyly of Mordellidae, Meloidae, Oedemeridae, Pyrochroidae, Salpingidae, Scraptiidae, Lagriidae, and Tenebrionidae, and the Mordellidae is close to the Ripiphoridae. The "Tenebrionidae clade" and "Meloidae clade" are monophyletic, and both of them are sister groups. In the "Meloidae clade," Meloidae is close to Anthicidae. In the "Tenebrionidae clade," the family Lagriidae and Tenebrionidae are sister groups. The divergence time analysis suggests that Tenebrionoidea originated in the late Jurassic, Meloidae Mordellidae, Lagriidae, and Tenebrionidae in the Cretaceous, Oedemeridae in Paleogene. The work lays a base for the study of mtgenome, phylogenetics, and evolution of the superfamily Tenebrionoidea. [ABSTRACT FROM AUTHOR]

Salinized lacustrine shale (SLS) represents a frontier in the global quest for unconventional hydrocarbon resources. The impact of terrigenous input, which includes terrigenous organic matter (OM) and detrital matter, on the deposition and hydrocarbon potential of SLS is still controversial. Here, we examine this issue using the newly discovered SLS within the Paleogene Biyang Depression, employing a combination of organic petrographic and geochemical analyses. A high influx of terrigenous input (terrigenous OM and detrital matter) promotes the formation of SLS. On the one hand, terrigenous higher plants emerge as the primary source of OM in the SLS, as indicated by the dominance of terrigenous macerals (e.g., terrigenous liptinite) and the abundance of plant-derived biomarkers (e.g., tricyclic terpanes). Additionally, a portion of the OM may originate from bacteria. On the other hand, the rapid input of detrital matter improves the preservation of OM, resulting in the deposition of SLS with high total organic carbon (TOC) contents and low hydrogen index (HI) values. The findings of this study contribute to a deeper understanding of SLS deposition and provide guidance for regional hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

Research on the geology, palaeontology and biostratigraphy of the Tertiary now extends back more than 200 years in Central Germany. Research experienced its first peak when E. Beyrich defined the Oligocene as a stage of the Early Tertiary (Palaeogene) in the middle of the 19th century. Outcrops in Central Germany played a key role during this time. Until the end of the 19th century, numerous authors examined the fauna, depositional conditions and stratigraphy of the Central German Tertiary. Beyrich and v. Koenen wrote eminent monographs on the Oligocene mollusc faunas as a basis for biostratigraphy. After this "heroic phase", things became rather quiet from the beginning of the 20th century onwards. The focus of research shifted to other fields and for a long time the above-mentioned works served as the definitive standard references. It was only after 1945 that a more intensive palaeontological-biostratigraphical investigation of the local Palaeogene began again. A large number of authors published material on micropalaeontological studies and step by step standard zonations based on foraminifera, nanoplankton, palynomorphs and dinocysts were established, published and continuously updated. In addition, molluscs were also revised and updated. Fish remains (selachian teeth and fish otoliths), as well as remains of fossil tetrapods, were examined in a modern way. Parallel to this, an intensive study of macrobotanical remnants was undertaken. Today, the region can be considered to have a first-class level of knowledge, to which, of course, the large open-cast lignite mines and numerous drillings for lignite exploration also contributed. Despite this enormous density of knowledge, however, questions remain unanswered. The Latdorfian mollusc fauna as a whole still needs a modern revision and despite the high level of investigation, surprising and outstanding finds are still possible, as the discovery of a rocky shore environment near Mammendorf or the drillings in the Latdorfian near Latdorf show. Moreover, the German division for decades has led to partly different views. Of course, this has to be brought together again. The article presented here is a comprehensive account of the development of knowledge concerning the Tertiary of Central Germany with a focus on geology, stratigraphy, palaeontology and palaeogeography. This finishes with a list of the literature cited. We do not include unpublished literature, such as the numerous reports on the results of lignite exploration during the GDR period, because these are not generally accessible. Furthermore, we do not take into account the countless works on mining and prospecting of mineral resources. Much of this is "grey" literature and/or outside our scope. [ABSTRACT FROM AUTHOR]

X-ray diffraction analyses (XRD) were performed on marine Palaeogene (Upper Eocene--Lower Oligocene) clay minerals from Central Germany (Schneidlingen 1/2018 research well). Geochemical and grain size analyses gave supporting information on eustatic controlled system tracts, transgressions, sediment supply and flow conditions during the time of sedimentation and served to structure the research well in the formations. Except for three transgressions, long-lasting steady flow conditions occurred in the forefield of the Central German Estuary ("Mitteldeutsches Ästuar" -- MdÄ). The clay mineral kaolinite could be identified as a delivery area indicator for the Central Saxon Hills ("Mittelsächsisches Hügelland"). The other studied clay minerals smectite, illite and chlorite indicate three cooling trends between or within the formations and the transition from a chemical to a physical weathering regime with the beginning of the Rupelsilt/-clay Subformation. Although there are hints for authigenic or early diagenetic influences, distinct changes within the clay mineral distribution describe prominent trends that correlate well with other insights from the sedimentation area. It has been shown be evidenced, that clay mineralogical studies of marine sediments from Central Germany can be used to determine source areas and climatic trends. [ABSTRACT FROM AUTHOR]

In this study, we combined low-t thermochronology with outcrop- to micro-scale kinematic and petrological observations in the metamorphic basement of the Juhor Mts. in Central Serbia. The Juhor Mts. comprise northern parts of the Europe-derived Serbo–Macedonian Unit, at the transition towards the Adria-derived tectonic units of the Internal Dinarides. The Late Paleozoic Variscan orogeny resulted in the medium-grade greenschist to amphibolite facies metamorphism in the core of the mountains, as inferred from our thin section-scale observations. During the subsequent Alpine orogeny, the tectonic setting of the entire Europe–Adria transitional area was strongly influenced by the geodynamic evolution of the intervening Neotethyan Vardar Ocean. The last recorded thermal overprint in the northern segments of the Serbo–Macedonian metamorphics occurred in the latest Jurassic due to their burial during the obduction of the Eastern Vardar ophiolites over the European continental margin. According to our thermochronological and field structural data, the exhumation of the Juhor Mts. metamorphic basement occurred during two separate phases of extensional deformations. During the Late Cretaceous extension, the Serbo–Macedonian metamorphics were exhumed for ~3 to 6 km along a ductile Morava shear zone, and later structurally juxtaposed against the low-grade metamorphics of the adjacent Supragetic Unit of the Serbian Carpathians. The latest phase of ~1 to 2,5 km tectonic exhumation and uplift in the Miocene took place along the brittle normal faults that accommodated the opening of the Morava Valley Corridor, which forms the southern prolongation of the Pannonian Basin. It is plausible, therefore, that these Miocene normal faults are reactivated segments of thrusts inherited from the preceding Paleogene phase of the Adria–Europe collision. [ABSTRACT FROM AUTHOR]

The quantitative estimation of key parameters of paleotemperature and paleoprecipitation is crucial for paleoclimate reconstruction. Geochemical data from modern sediments are highly consistent with climate data, and their relationship can provide an important reference for the quantitative reconstruction of the paleoclimate. In this study, detailed inorganic geochemical analysis was carried out using high-precision sampling of the Paleogene (LFD-1 well) Guchengzi, Jijuntun and Xiloutian Formations in the Fushun Basin located in the mid-latitudes of the Northern Hemisphere. The Eocene Guchengzi Formation (54.51–47.8 Ma) and Jijuntun Formation (47.8–41.2 Ma) in the Fushun Basin were found to have been deposited under a humid climate. The lower (41.2–40.1 Ma) and upper (40.1–37.8 Ma) parts of the Xiloutian Formation were characterized by semiarid and semihumid–semiarid climates, respectively, which is very similar to the paleoclimatic information reflected by organic carbon isotopes. The Eocene Thermal Maximum 2 (ETM2, ~ 53.7 Ma), Early Eocene Climatic Optimum (EECO, ~ 53.1–46.5 Ma, Eocene Thermal Maximum 3 (ETM 3, ~ 52.8 Ma), and Middle Eocene Climatic Optimum (MECO, ~ 40.7–40.1 Ma) events significantly enhanced chemical weathering during these periods. The rapid increase in pCO2 concentration leads to an increase in temperature, precipitation, and surface runoff, exhibiting strong chemical weathering. The mean annual temperature (MATa) and mean annual precipitation (MAPa, MAPb, and MAPc) were estimated using parameters, such as the corrosion index without potassium (CIA-K), CaO/Al2O3, and (Na2O + K2O)/Al2O3. Comparing MAPa, MAPb, and MAPc with the MAP estimated using pollen data, MAPa and MAPb were found to be more sensitive to the climate during high precipitation periods (precipitation > 1000 mm, Guchengzi Formation), and the recovered average precipitation was similar to MAP. In contrast, MAPc was more sensitive to the climate during low precipitation periods (precipitation < 1000 mm, Jijuntun, and Xiloutian Formations), with higher accuracy. To fully consider the influence of soluble inorganic salts Ca2+ and Na+, multivariate linear equations of CIA-K and CaO/Al2O3 with CIA, and CIA-K and CaO/Al2O3 with MAP were constructed, namely MAPd and MAPe. The results show that MAPe has the highest performance and can be effectively used to estimate the change of paleoprecipitation in Northeast Asia. [ABSTRACT FROM AUTHOR]

The U–Pb detrital zircon record of the Surat Basin, an important part of the Great Australian Superbasin, has already revealed important insights about sediment source terranes. However, owing to the high closure temperature of zircons, low-temperature thermal events that might have impacted the sediment are not recorded. Here, new 40Ar/39Ar detrital mica ages, which record low-temperature events as a result of isotopic resetting, are paired with published U–Pb detrital zircon ages from the same samples to provide a more complete interpretation of the tectonic and thermal history of the Jurassic-age Precipice Sandstone and Evergreen Formation. The 40Ar/39Ar geochronology of mica grains from five wells reveals two broad groups with distinct age populations: 1500–180 Ma and 150–45 Ma. Micas older than about 180 Ma are sourced from multiple terranes. The slight discrepancy in ages between the 40Ar/39Ar and the U–Pb systems of the same samples may represent differences in closure temperature. However, some micas, such as those dating to ca 180 Ma, may also reflect a thermal reset event. Similarly, the younger group of micas, split into Cretaceous and Paleogene populations, reflect the impact of post-depositional thermal events on the basin. Isotopic resetting of the micas was likely the result of hydrothermal fluids migrating through reactivated faults, fractures and/or porous and permeable sediments. The origin of the fluids during the Cretaceous can be linked to an eastern subduction zone and subsequent igneous underplating resulting in uplift and denudation. The exact source of the hydrothermal fluids for the micas of Paleogene age, recorded in samples collected from the base of the Evergreen Formation, however, remains uncertain. Importantly, 40Ar/39Ar dating of mica from sandstones permits the detection of post-depositional thermal events that may have implications for tracing fluid migration throughout the basin and reconstructing the Cretaceous–Paleogene tectonic history of the basin. Combining 40Ar/39Ar dating of micas with U–Pb dating of zircons reveals a more complete tectonic and thermal history of the Jurassic-age Precipice Sandstone and Evergreen Formation of the Surat Basin. 40Ar/39Ar dating of detrital micas reveals two broad groups with distinct age populations: 1500–180 Ma and 140–45 Ma. Ages older than ca 180 Ma are linked to multiple source terranes, including the Thomson and New England orogens, and the contemptuous magmatic arc. Ages younger than 150 Ma are most likely the result of post-depositional thermal resetting events, which may have implications for fluid movement throughout the basin. [ABSTRACT FROM AUTHOR]

Lamellar calcite veins are prevalent in carbonate-rich, lacustrine dark shale. The formation mechanisms of these veins have been extensively debated, focusing on factors such as timing, depth, material source, and driving forces. This paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression, using various analytical techniques: petrography, isotope geochemistry, cathodoluminescence, inclusion thermometry, and electron probe micro-analysis. Two distinct types of calcite veins have been identified: granular calcite veins and sparry calcite veins. These two types differ significantly in color, grain structure, morphology, and inclusions. Through further investigation, it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter, with a transition from granular calcite veins to sparry calcite veins. The granular calcite veins exhibit characteristics associated with the shallow burial period, including plastically deformed laminae and veins, the development of strawberry pyrite, the absence of oil and gas, weak fractionation in oxygen isotopes, and their contact relationship with sparry calcite veins. These granular calcite veins were likely influenced by the reduction of sulfate bacteria. On the other hand, sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic matter. They contain oil and gas inclusions and show a distribution range of homogenization temperature between 90 °C and 120 °C and strong fractionation in oxygen isotopes, indicating formation during the hydrocarbon expulsion period. The carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself, specifically authigenic micritic calcite modified by the action of methanogens. The opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarbon expulsion. Veins may form rapidly or through multi-stage composite processes. Early veins are predominantly formed in situ, while late veins are a result of continuous fluid migration and convergence. Furthermore, the veins continue to undergo modification even after formation. This study emphasizes that the formation of lamellar calcite veins in shale is a complex diagenetic process influenced by multiple factors: biology, organic matter, and inorganic processes, all operating at various stages throughout the shale's diagenetic history. [ABSTRACT FROM AUTHOR]

The controlling factors of organic-rich shale accumulation is essential for the exploration and development of shale oil and gas resources. The sedimentary environment plays a vital role in the formation of organic-rich sediments in lacustrine facies. This article unravels the mineralogy, geochemistry, and paleoenvironmental evolution during the deposition of the Paleogene Shahejie Formation (Es3 L). It discusses the effects of paleoclimate, paleosalinity, paleoredox conditions, paleowater depth, and paleoproductivity on organic matter (OM) enrichment. Finally, the OM enrichment model was established. The results show that the mineralogical compositions are mainly composed of calcite (avg. 40.13%), quartz (avg. 21.64%) and clay minerals (avg. 24.07%), accompanied by dolomite (avg. 7.07%), feldspar (avg. 6.36%) and pyrite (avg. 2.95%). The Es3 L shale has a high abundance of OM, with total organic carbon (TOC) ranging from 1.07% to 5.12%. The organic matter type is mainly composed of type I-II1 kerogen, which is generally considered a good-quality source rock. The source of OM is a mixture of lower bacteria, algae, and plants. During the early sedimentary period, the paleoclimate was dry and cold, with high salinity, intense reducibility, and relatively low productivity. During the late sedimentary period, the climate became warmer and more humid. As a result, the salinity decreased to a level that was suitable for biological reproduction, and productivity increased gradually due to the input of terrigenous plants. Paleosalinity and paleoclimate determined the environment of the sedimentary period, in addition, paleoproductivity and paleoredox condition indicated the formation and preservation conditions of OM. The warm and humid climate, brackish water, suitable reduction conditions and high productivity are the favorable conditions for the generation and preservation of organic matter. The research results may have implications for the genetic mechanisms of organic matter accumulation. They will provide theoretical and technical insights into the exploration and development of shale oil. [ABSTRACT FROM AUTHOR]

Sharks are virtually absent from coastal Antarctica since the Late Eocene glaciations, but this group exhibited a notable austral diversity during the Cretaceous and Paleogene. Several species have already been described from the Aptian-Eocene successions of the Larsen Basin exposed in the James Ross Island area (northern Antarctic Peninsula) and the predominantly deep-water Hexanchiformes have a record that, although still rare, has been continually increased. Four species of this group are currently known from that basin: Notidanodon pectinatus, Xampylodon dentatus, Rolfodon thompsoni, and Rolfodon tatere. Such records are especially concentrated in the Gamma Member of the Snow Hill Island Formation (or Herbert Sound Member of Santa Marta Formation), on James Ross Island. Here we described four teeth assigned to X. dentatus and one identified as R. tatere from upper Campanian sections of James Ross Island, highlighting the nomenclatural changes that led to the definition of Xampylodon and Rolfodon. Some specimens of X. dentatus presented here are considerably more complete or represent teeth of different positions than most previous records. The material assigned to R. tatere represents the oldest record of this species in the world, extending its time range by more than 10 million years. [ABSTRACT FROM AUTHOR]

Ray-finned fishes, which compose nearly half of living vertebrate diversity, provide an excellent system for studying the evolution of novel body forms. Lampriformes is a species-poor lineage of acanthomorph ray-finned fishes that has evolved two very different and highly specialized body plans suited to life in pelagic oceanic habitats: the deep, round-bodied bathysomes and the ribbon-like taeniosomes. Here, we present a new phylogenetic hypothesis and divergence time estimates for lampriform fishes based on an updated morphological dataset and DNA sequences from nuclear genes for all but one of the living lampriform families and 55% of recognized extant genera. Our analyses resolve two major clades in Lampriformes: the Bathysomi and the Taeniosomi. A time calibrated phylogeny shows that the origin of living lampriforms coincides with the aftermath of the Cretaceous–Palaeogene extinction and that anatomically modern pelagic morphotypes evolved 10 Myr after the start of the Palaeogene. [ABSTRACT FROM AUTHOR]

Observations show that mesospheric clouds (MCs) have been increasing in recent decades, presumably due to increased mesospheric water vapor which is mainly caused by greater methane (CH4) oxidation in the middle atmosphere. Past warm climates such as those of the early Cretaceous and Paleogene periods are thought to have had higher CH4 concentrations than present day, and future CH4 concentrations will also likely continue to rise. Here, idealized atmosphere chemistry‐climate model experiments forced with strong polar‐amplified sea‐surface temperatures and elevated carbon dioxide (CO2) and CH4 concentrations predict a substantial spreading of MCs to middle and low latitudes, well beyond regions where they are currently found. Sensitivity tests show that increased water vapor from CH4 oxidation and cooling from increased CO2 and CH4 concentrations create favorable conditions for cloud formation, producing MC fractions of 0.02 in the low latitudes and 0.1 in the mid‐latitudes in the Northern Hemisphere when CH4 concentration is 16× higher than pre‐industrial. Further increases in CH4 result in a monotonic increase in low‐ and mid‐latitude MCs. A uniform surface ocean warming, changes in polar amplification, or the solar constant do not significantly affect our results. While the appearance of these clouds is interesting, their ice and liquid water content is not sufficient to cause a significant radiative effect. On the other hand, dehydration of the mesosphere due to these low‐ and mid‐latitude MCs could potentially lead to a reduction in atomic hydrogen, thereby affecting mesospheric ozone concentration, although further study is required to confirm this. [ABSTRACT FROM AUTHOR]

The Antarctic Digital Magnetic Anomaly Project is an international research effort to construct a magnetic map of the continent based on ground, satellite, marine, and aeromagnetic surveys. This paper reports the magnetic mapping of the shelf zone in the SE part of the Wilhelm Archipelago, West Antarctica, based on magnetic surveys conducted with Zodiac boats. A spectacular feature of this area is the strong magnetic anomaly of the Antarctic Peninsula (AP) batholith, which was the product of subduction-related Mesozoic–Cenozoic arc magmatism on the former margin of Western Gondwana. We constructed and analyzed a detailed magnetic map of magnetic field anomalies using field observations of rock exposures on the islands and magnetic properties of rocks from laboratory data. The oldest volcanic rocks of Jurassic to Lower Cretaceous age relate to N-NE trending bands of negative magnetic field. The largest feature in the study area is an Upper Cretaceous/Paleogene granodiorite complex that produces a positive magnetic anomaly. Many smaller anomalies are also present over gabbroid bodies of Cretaceous age. Two-dimensional magnetic modeling shows that heterogeneities in the upper crust may have magnetic susceptibilities in the range of 0.005–0.13 SI. Magnetic field anomalies also delineate an orthogonal system of tectonic faults, including the main NE fault along the Penola Strait (sub-parallel to the AP coastline) and four intersecting faults. These fault systems may be associated with different stages of continental margin evolution along the Antarctic Peninsula. [ABSTRACT FROM AUTHOR]