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Estimates of cetacean abundance in European Atlantic waters in summer 2022 from the SCANS-IV aerial and shipboard surveys
No full textGeochemical records and environmental analysis of the Ediacaran-Cambrian boundary in Eastern Yunnan, South China
No full textThe Ediacaran–Cambrian transition is characterized by an unprecedented change in biosphere, lithosphere, and atmosphere. However, the identification of this transition and its global correlation remains debated. East Yunnan is a region of utmost importance in the study of the Ediacaran-Cambrian transition. Although strata from this region have been well studied, recognition of the base of the Cambrian continues to be controversial. This paper presents, a carbon chemostratigraphic isotope and trace element profile through the Dengying and Zhujiaqing formations in the Sujiawa section in East Yunnan. Through carbon isotope and trace element analyses of the Dengying and Zhujiaqing formations we attempt to regionally correlate the section and discuss the paleo-marine redox environment changes during this period. The Fe content of samples is low and the Mn/Sr ratios of the majority of the Sujiawa section samples is lower than 10 and shows no correlations with δ13Ccarb and δ18Ocarb values, indicating that the samples retain near-primary δ13Ccarb characteristics. The carbon isotope profile from the Sujiawa section, shows a prominent negative δ13Ccarb in the basal Zhongyicun Member (N1’, −7.3‰) that most likely represents the prominent negative excursion recorded in Ediacaran-Cambrian strata across the world. REE patterns and Y/Ho ratios were used to screen samples, to ensure that the primary seawater REE features and Ce anomalies were preserved. The samples satisfying this screening process show seawater-like REE distribution patterns in leached carbonates and may have recorded Ce anomalies of the seawater from which the carbonates precipitated. These data show that the Baiyanshao Member has Ce/Ce* values between 0.57 and 0.88, the Daibu Member between 0.56 and 0.83, and the Zhongyicun Member between 0.60 and 0.96. The Ce anomalies through the section indicates that the region experienced suboxic-oxic-anoxic conditions throughout the Ediacaran-Cambrian period. Carbon isotope and trace element analyses indicate that the strata record a negative carbon isotope excursion event and anoxic conditions during the period of deposition. This study complements the carbon chemostratigraphic information and trace element data in the region and provides valuable clues for understanding the lithofacies changes through the Ediacaran and Cambrian in different regions of South China
Detrital Garnet Geochronology by In Situ U‐Pb and Lu‐Hf Analysis: A Case Study From the European Alps
No full textThermal treatment of the tourmaline Fe-rich princivalleite Na(Mn2Al)Al6(Si6O18)(BO3)3(OH)3O
No full textMorphological and molecular characterization of Encotyllabe vallei Monticelli, 1907 (Monopisthocotylea, Monogenea) from the gilthead seabream Sparus aurata Linnaeus (Teleostei, Sparidae) from the southwestern Mediterranean and notes on host specificity of the genus Encotyllabe Diesing, 1850
No full textIncomplete original descriptions, the unavailability or poor conditions of specimens and the lack of detailed redescriptions have caused the validity of several species of the genus Encotyllabe Diesing, 1850 to be questioned. To date, seven of the recognized species were described upon one or two specimens, hindering study of intraspecific variations. This was made worse by considering few morphoanatomical differences sufficient to erect new species. Among Encotyllabe spp. occurring in Mediterranean waters, E. vallei was first described from the gilt-head bream Sparus aurata (Sparidae) off Italy. Although beautifully illustrated for a paper from that century, morphometric data for E. vallei from the type-host S. aurata remain unavailable. Previous records of E. vallei provided either morphometrical or molecular data, and its validity was questioned. We provide a redescription of E. vallei based on newly collected specimens from the S. aurata from the southwestern Mediterranean (off Algeria) using integrative taxonomy. Analysis of cox1 sequences of E. vallei from S. aurata, compared to sequences from other sparid hosts, mainly Pagellus bogaraveo, revealed a divergence not exceeding 2%, suggesting a stenoxenic specificity for this monogenean. Given that P. bogaraveo is the type-host for Encotyllabe pagelli, we were tempted to suggest a synonymy between E. vallei and E. pagelli. We refrained from doing so because E. pagelli was first described from the Atlantic coast off Brest, France. Morphological data for Encotyllabe from P. bogaraveo are warranted assessing the host specificity of E. vallei and whether there might be a species complex within individual sparid fish species
Marginal leaf galls on Pliocene leaves from India indicate mutualistic behavior between Ipomoea plants and Eriophyidae mites
No full textWe report a new type of fossil margin galls arranged in a linear series on dicot leaf impressions from the latest Neogene (Pliocene) sediments of the Chotanagpur Plateau, Jharkhand, eastern India. We collected ca. 1500 impression and compression leaf fossils, of which 1080 samples bear arthropod damage referable to 37 different damage types (DT) in the ‘Guide to Insect (and Other) Damage Types in Compressed Plant Fossils’. A few leaf samples identified as Ipomoea L. (Convolvulaceae) have specific margin galls that do not match any galling DT previously described. This type of galling is characterized by small, linearly arranged, irregular, sessile, sub-globose, solitary, indehiscent, solid pouch-galls with irregular ostioles. The probable damage inducers of the present galling of the foliar margin might be members of Eriophyidae (Acari). The new type of gall suggests that marginal gall-inducing mites on leaves of Ipomoea did not change their host preference at the genus level since the Pliocene. The development of marginal leaf galling in Ipomoea is linked to extrafloral nectaries that do not offer protection against arthropod galling but indirectly protect the plant against herbivory from large mammals
Ediacaran cap carbonates with microbial build-ups capping barite-bearing methane seep networks in the Kaarta Mountains, Taoudeni Basin, Mali
No full textThe development of dark shales from the middle and late Cambrian to early Ordovician on the East European Platform – with focus on Gotland
No full textBy compiling data from literature and unpublished reports a more detailed description is presented on the geographical and stratigraphic distribution of the Alum Shale Formation (ASF) and correlateable units on the East European Platform. In the northern part of Gotland, downfaulted patchy beds of the ASF indicate a former wider extension of the formation. Lower Ordovician (Tremadocian) examples of downfaulted patchy beds are the contemporaneous Sepopol and Nivenskaya formations in northeastern Poland and the Kaliningrad area, as well as the Salantai Formation in the east Baltic area. It is indicated that Furongian-Tremadocian beds, contemporaneous with the Kallavere, Türisalu, Tosna and Koporye formations, in the area of northern Estonia and the northwestern part of the Moscow Basin, extended to the Gotland and the South Bothnian Basin areas. South of Gotland, in the Swedish sector of the Baltic Basin, drill cores show evidence of tectonic movements through the presence of erosional surfaces indicating occasional subaerial exposure. In this region, variations in the areal extent and thickness of the ASF and coeval formations are suggested to be the result of epeirogenic and tectonic block movements. Tremadocian ASF is also indicated to be present south of Gotland. On Gotland, at least 5 m of the ASF is presumed to have been eroded. The Moscow Basin contains 19 m of dark shales (Koporye Formation) which is significantly thicker than in surrounding areas.Svenska Petroleum Exploration AB is thanked for giving access to unpublished reports. The Geological Survey of Sweden (SGU) is also very much thanked for letting us have access to the Grötlingbo-1 and B-7 cores.</p
How similar are the venation and cuticular characters of Glossopteris, Sagenopteris and Anthrophyopsis?
No full textVenation architectures and cuticular micromorphology of leaf fossils play important roles in higher-level taxonomic segregation, as these characters are broadly fixed within major plant clades. Three common fossil plant taxa are characterized by similar-shaped leaves or leaflets and anastomosing venation to such an extent that examples have commonly been assigned to the wrong taxon in past studies where fragmentary or ill-preserved material is available. We use standardized descriptions of vein cross-connection types and stomatal features to compare and contrast the venation patterns and stomatal architectures of these genera. Our reanalysis of the macro- and micromorphology of Glossopteris, Sagenopteris and Anthrophyopsis leaves reveals important differences that help segregate these taxa even on the basis of incomplete specimens. Anthrophyopsis has distinctive alignments of vein cross-connections in the outer lamina and paracytic stomata consistent with those of Bennettitales. Glossopteris has perigenous and monocyclic—normally stephanocytic to actinocytic—stomata commonly protected in pits or by overarching papillae. Sagenopteris has more consistently evanescent midribs and surficial anomocytic or stephanocytic stomata with weakly modified subsidiary cells. Considering the putatively close relationship of glossopterids (Glossopteris), Caytoniales (Sagenopteris) and Bennettitales (here encompassing Anthrophyopsis) resolved as members of the ‘glossophyte’ clade in some past phylogenetic studies, cuticular features suggest that these groups are not closely related. In addition, anastomosing venation, superficially similar to that of Glossopteris, Sagenopteris and Anthrophyopsis appears to have arisen independently in numerous other plant groups suggesting that this character has ecological or physiological benefits and is strongly prone to homoplasy.This study is financially supported by the National Natural Science Foundation of China (grant numbers 42072009, 41790454), the Stratigraphic Priority Program (B) of the Chinese Academy of Sciences (grant number XDB 2610302), the Programs from State Key Lab of Palaeobiology and Stratigraphy (20191103, 213112), and CSC (grant number 202204910396). S.M. is funded by grants from the Swedish Research Council (VR grant numbers 2018-04527 and 2022-03920).</p
Н2 – ВОДЕНЬ ЕКОЛОГІЧНЕ ДЖЕРЕЛО ДЕКАРБОНІЗАЦІЇ — ШЛЯХ ДО ЕНЕРГЕТИЧНОЇ НЕЗАЛЕЖНОСТІ УКРАЇНИ
No full textThe research studied the pressing problem of the fuel and energy strategy of the XXI century. For the first time, there was shown the diversity of the authors' approach to theoretical and applied problems of hydrogen energy. General issues of fundamental and applied aspects of hydrogen origin were covered. The study provides the results of scientific developments on hydrogen mapping performed within the framework of scientific and practical exploratory and geo-ecological research on more than 200 hydrocarbon objects both on land (including mining fields) and in marine water areas. Prognostic and search system criteria were substantiated, with hydrogen being used for the first time as a component of the complex of methodical solutions in the search practice. The research showed the importance of solving the problem of geo-ecological processes and accidents in mine workings and wells, connected to numerous disasters. According to numerous studies of mine massives, a set of preventive measures and criteria that prevent explosive processes was provided.The presence of a unique complex of natural components of hydrogen technology, solar and wind energy resources and fresh waters of the Danube lakes and the Danube was stated.The study emphasises the decisive role of Ukraine in the competition for primacy in scientific developments. For the first time in world practice, the implementation of global projects for the extraction and production of green and white hydrogen was substantiated.The technology was tested on numerous hydrocarbon deposits, water resources and mine workings and therefore has all the prospects for the effective application in the search and extraction of hydrogen. This monograph can be useful and informative for specialists in the fields of oil and gas geology, general and regional geology, hydrology, environmental protection, as well as for the students and postgraduate students of fuel and energy, oil and gas geological and hydrological areas, as well as for domestic and foreign investors.Розглянуто актуальнішу проблему паливно-енергетичноїстратегії XXI ст. Вперше продемонстровано різновек-торність підходу авторів до теоретичних та прикладних проблем водневої енергетики.Висвітлено загальні питання фундаментально-прикладнихаспектів походження водню.Наведено результати наукових розробок з картування водню, виконаних у рамках наукових і практичних пошу-кових і геоекологічних досліджень на понад 200 вуглеводневих об'єктах на суходолі (включаючи шахтні поля) та в мор-ських акваторіях. Обґрунтовано прогнозно-пошуковісистемні критерії, де складовою частиною комплексу методичнихрішень вперше в пошуковій практиці використовувався водень.Показано важливість вирішення проблеми геоекологічних процесів і подій у шахтних виробках та свердлови-нах, з якими пов’язані численні катастрофи. За численними дослідженнями шахтних масивів наводиться розробленийкомплекс упереджувальних заходів та критеріїв, що унеможливлюють вибухонебезпечні процеси.Наведено наявність унікального природного комплексу складових водневої технології, сонячних та вітровихенергоресурсів та прісних вод придунайських озер та Дунаю.Відображено вирішальну роль України в змаганні за першість в наукових розробках. Вперше в світовій практиціобґрунтовано впровадження глобальних проектів по видобуванню та виробництву зеленого та білого водню.Технологія апробована на численних родовищах вуглеводнів, водних ресурсів і в шахтних виробках і тому маєвсі перспективи для ефективного застосування при пошуках і видобутку водню.Ця монографія може бути корисною та інформативною для фахівців у галузі геології нафти і газу, загальноїта регіональної геології, гідрології, охорони довкілля, студентів та аспірантів паливно-енергетичного,нафтогазогео-логічного і гідрологічного напрямів, а також вітчизняних і зарубіжних інвесторів