Swedish Museum of Natural History
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Igelströmite, Fe3+(Sb3+Pb2+)O4, and manganoschafarzikite, Mn2+Sb3+2O4, two new members of the newly established minium group, from the Långban Mn–Fe deposit, Värmland, Sweden
No full textThe two new minerals igelströmite, Fe3+(Sb3+Pb2+)O4, and manganoschafarzikite, Mn2+SbO4, are found in the Långban Fe–Mn deposit, in open fractures in a fine-grained hematite ore, with minor amounts of aegirine, a serpentine-group mineral, fluorcalcioroméite, baryte, nadorite, mimetite and other late-stage minerals. Igelströmite is named after the Swedish geologist–mineralogist Lars Johan Igelström (1822–1897). Mohs hardness = 3–4 and Dcalc= 6.33(1) and 5.37(2) g cm−3 for igelströmite and manganoschafarzikite, respectively. Cleavage is distinct on {110}. Both minerals are brittle, with an uneven to conchoidal fracture. The chemical formulae obtained from microprobe data are (Fe3+0.59Mn2+0.29As3+0.06Fe2+0.06)Σ=2.00(Sb3+1.24Pb2+0.65As3+0.11)Σ=2.00O4 and (Mn2+0.64Fe3+0.25Mg2+0.08)Σ=0.97(Sb3+1.97As3+0.03Pb2+0.01)Σ=2.01O4. The crystal structures for igelströmite and manganoschafarzikite have been refined in space group P42/mbc from single-crystal X-ray diffraction data to R1 = 3.73% and 1.51%, respectively, giving the following sets of unit-cell parameters: a= 8.4856(2), 8.65159(8) Å; c= 6.0450(3), 5.97175(9); and V= 435.27(3), 446.986(11) Å3 for Z = 4. Both minerals are isostructural with minium, Pb4+Pb2+2O4, where Pb4+O6 forms distorted octahedra, which connect via trans-edges to form rutile-like ribbons along c. The Pb2+ atoms appear in trigonal, flattened PbO3 pyramids, which are linked via corners to form zigzag (PbO2)n chains. The minium group, of general formula MX2O4(X= As3+, Sb3+, Pb2+), presently consists of the minerals minium, trippkeite, schafarzikite, igelströmite and manganoschafarzikite. For future new members, it is recommended to consider the X cation content for the root name and add prefixes to indicate the dominant metal at the M position
Subduction and loss of continental crust during the Mesoproterozoic Sveconorwegian Orogeny
No full textThe late Mesoproterozoic Sveconorwegian Orogeny in SW Fennoscandia is characterized by tectonically bound units that record different metamorphic, magmatic, and deformation histories, interpreted to indicate separation by some unknown distance prior to orogeny. New zircon U–Pb and Lu–Hf isotope data from a 1200 km-long NE–SW transect including Archean to 1450 Ma rocks constrain the likely age and isotopic architecture of western Fennoscandia prior to the late Mesoproterozoic Sveconorwegian Orogeny. Zircon age and Hf-isotope patterns indicate that the units comprising the Sveconorwegian Province are both younger and isotopically more juvenile than the surrounding autochthonous Fennoscandian crust, and thus most likely derived from west of the present-day Norwegian coastline. The Mylonite Zone defines a major tectonic structure separating allochthonous Sveconorwegian units in its hanging wall from autochthonous Fennoscandian crust in its footwall. New and compiled metamorphic age data demonstrate that the Mylonite Zone can be traced westward through the Western Gneiss Region, aligning with Nordfjord in western Norway, where it was reused during Caledonian deformation. The proposed westward continuation of the Mylonite Zone accommodated several hundred kilometers of sinistral strike-slip movement. Eastward translation of crust probably took place sometime between 1020 and 990 Ma, coinciding with a magmatic lull, followed by a shift to more evolved isotopic compositions in the hanging wall (Telemark) and high-pressure eclogite-facies metamorphism in the footwall (Eastern Segment) to the Mylonite Zone. Following this relatively short period of compression, the entire orogen and its foreland underwent extension lasting until at least 930 Ma. The nature and fate of the ca. 500 km of crust originally separating the autochthonous and allochthonous units remain elusive. There is no evidence of arc magmatism related to Benioff-style subduction of oceanic crust, and thus we propose an amagmatic Ampferer-style subduction comprising spontaneous subduction of thinned continental crust, as proposed for the Western Alps. Subduction of continental crust and associated radioactive heat-producing elements could also account for the anomalously high temperatures in the lithospheric mantle under the Sveconorwegian Province, which cannot easily be accounted for by other mechanisms. The Sveconorwegian Province may be an anomalous feature in an otherwise larger-scale orogen, the nature of which remains obscure
Jurassic system stratigraphy at the Kamianka village. Part 2. The Cherkas’ka formation
No full textIntroduction. The paper is devoted to the study of the Cherkaska formation of the Jurassic system of the North-Western outskirts of the Donbas and is a continuation of a series of publications highlighting the stratigraphy of Jurassic in key areas near the town of Izyum and the village of Kamyanka. Material and methods. The scientific search was based on the analysis of literature, results of previous drilling and mapping works, as well as own field, laboratory and analytical studies. Chemical and X-ray structural analyzes of clays, mineralogical analysis of sands were carried out. Micropaleontological analysis and generalized data on the distribution of fossil remains were carried out. The palynological analysis of these deposits was also carried out, including, for the first time, according to the orthostratigraphic group – dinocysts. Results and discussion. The stratotype of the Cherkaska Formation was not specified. These were probably outcrops of ferruginous sandstones in the area of the village of Cherkaske, Slavic district, Donetsk region. Unfortunately, the deposits of this formation are exposed very fragmentarily, which makes it impossible to indicate a single typical section. As a number of such sections, it is possible to indicate Topalska balka - a clay stratum, and Pidluzhnyi farm -the upper stratum, stratigraphically important Vitcheliian layers were noted only in the village of Sukha Kamianka.Lithology. In this section of the paper, we present the detailed lithological composition of the deposits of the Cherkaska Formation from the three studied outcrops. Paleontological remains. Based on the findings of macrofauna in the sandstones, the dated levels of Witchellia rossica and Stephanoceras humphriesianum can be distinguished, which correspond to the two upper zones of the Lower Bajocian of the International Stratigraphic Scale. Upon the appearance of dinocysts of Pareodinia sp. and a small percentage of Clasopollis pollen (remains of gymnosperms) for the first time dated clays of the Cherkaska subformation. Stratigraphy. Within the studied territory, the Cherkaska formation is clearly divided into two parts: the lower one, composed of clays, and the upper one, composed of sandstones, which makes it possible to divide it into subformation. Witchellia limestone may be present if the upper sub-formation is eroded. Paleogeography. At the beginning of the Cherkaskyi period, the territory was a flat lowland covered by an extremely shallow sea basin. In the Late Cherkaskyi period, the supply of detrital material increases significantly, but the depth of the basin also increases, the salinity becomes normal, and a normal marine fauna appears. In some places, on the slopes of paleo-elevations, accumulation does not occur, which leads to the formation of deposits of a facies similar to Ammonitico rosso - limestones from Witchellia. Conclusions. The Cherkaska formation represents an important stage in the geological history of the development of northwestern Donbas. The formation marks the beginning of the Middle-Late Jurassic transgression, the beginning of the formation of normal marine sediments, and the activation of differentiated tectonic movements of local structures. У цій публікації висвітлено резуль-тати палінологічних досліджень виконаних у рамках бюджетної теми «Біостратиграфія мезо-кайнозойських відкладів нафтогазоносних регіо-нів України як фундаментальна основа систем-ного забезпечення геологічних робіт», що розро-бляється в Інституті геологічних наук НАН Укра-їни (номер державної реєстрації 0122U001604) та частково профінансована.</p
Colonial-driven extinction of the blue antelope despite genomic adaptation to low population size
No full textLow genomic diversity is generally indicative of small population size and is considered detrimental bydecreasing long-term adaptability. Moreover, small population size may promote gene flow with congeners and outbreeding depression. Here, we examine the connection between habitat availability, effective population size (Ne), and extinction by generating a 40x nuclear genome from the extinct blue antelope (Hippotragus leucophaeus). Historically endemic to the relatively small Cape Floristic Region in southern-most Africa, populations were thought to have expanded and contracted across glacial-interglacial cycles, tracking suitable habitat. However, we found long-term low Ne, unaffected by glacial cycles, suggesting persistence with low genomic diversity for many millennia prior to extinction in AD 1800. A lack of inbreeding, alongside high levels of genetic purging, suggests adaptation to this long-term low Ne and that human impacts during the colonial era (e.g., hunting and landscape transformation), rather than longer-termecological processes, were central to its extinction. Phylogenomic analyses uncovered gene flow between roan (H. equinus) and blue antelope, as well as between roan and sable antelope (H. niger), approximatelyat the time of divergence of blue and sable antelope (1.9 Ma). Finally, we identified the LYST and ASIP genes as candidates for the eponymous bluish pelt color of the blue antelope. Our results revise numerous aspects of our understanding of the interplay between genomic diversity and evolutionary history and provide the resources for uncovering the genetic basis of this extinct species’ unique traits
The Swedish Aeolothripidae and Melanthripidae (Thysanoptera) with a Redescription of Rhipidothrips niveipennis Reuter, 1899
No full textThis study explores the Swedish diversity of the thrips families Aeolothripidae and Melanthripidae. Currently, a total of 12 species in 2 genera of Aeolothripidae occur in Sweden, and 1 in Melanthripidae. The aims of this study include to provide an updated identification key with photographic material and an updated checklist of the country with provincial records. In this study both museum material and new material collected in understudied provinces are included, and a large number of molecular barcodes are produced. The results reveal 26 new provincial records in Sweden, predominantly in northern regions, and 11 provinces in total had new species records. New records of Rhipidothrips brunneus Williams 1913 warranted an examination of distinguishing characters compared to R. niveipennis Reuter, 1899. The original description of R. niveipennis is found to lack sufficient characters to delimit the species, and a redescription based on syntypes is presented
PCDD/Fs and dl-PCBs within the Swedish National Monitoring Program for Contaminants in Marine Biota
No full textInvestigation of Spatiotemporal Patterns of Harbour Porpoise (Phocoena phocoena) Strandings in Swedish Waters for Improved Monitoring and Management
No full textPopularization and linguistic aspect of the scientific works of the Ukrainian palynologist, Doctor of Geological and Mineralogical Sciences Margarita Artemiivna Voronova
No full textBibliography of the Doctor of Geological and Mineralogical Sciences M.A. Voronova was created by her graduate student and follower, Doctor of Geological Sciences O.A. Shevchuk for popularizing the unique palynological works of Margarita Artemievna and integrating them into the global scientific and educational space with the aim of digitizing data. Bibliography of M.A. Voronova is laid out step by step, according to the year of publication, each publication is transliterated according to the new rules and translated into English. Archive materials of the case of M.A. Voronova were used in the formation of the bibliography stored in the Institute of Geological Sciences of the National Academy of Sciences of Ukraine. M.A. Voronova is a specialist in palynology of the Cretaceous flora of Ukraine. She worked at the Institute of Geological Sciences of the National Academy of Sciences of Ukraine until 2002. The results of her research are presented in 149 scientific works, including 3 monographs of her own and 7 co-authored. The main object of her research was fossil spores and pollen from the Late Jurassic-Cretaceous deposits of Ukraine. Her scientific interests covered various aspects of geological and biological knowledge. Margarita Artemiivna developed new concepts of the evolution of Cretaceous floras, as well as developed criteria for paleolandscape reconstructions for the Early Cretaceous of Ukraine. MA. Voronova studied the oldest angiosperms of the territory of Ukraine: the time of their appearance, the morphology of their pollen grains in order to establish phylogenetic relationships. As a result of palynological studies, Margarita Artemiivna established for the first time the distribution of continental Barremian, Aptian, and Albian deposits in the Dnipro-Donetsk basin, the Ukrainian shield, and the Black Sea basin, and she also identified types of miospores, the findings of which can serve as a sign for the detection of bauxite-bearing strata and reporting crusts. All these studies are presented in monographs "Miospores of the Early Cretaceous of Ukraine" and "Palynostratigraphy of the Lower Cretaceous and the Development of Early Cretaceous Flora of Ukraine" and others. Having analyzed the scientific publications of M.A. Voronova, it was concluded that the palynologist more often used the Russian language to present her scientific results, but still the first publications were printed in Ukrainian, and after the declaration of independence of Ukraine, we observe the restoration of the Ukrainian language in the works of the palynologist
