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  • 1. BADAWY, AHMED SALAH
    et al.
    Mehlqvist, Kristina
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology.
    Ahlberg, Per
    Calner, Mikael
    Late Ordovician (Katian) spores in Sweden: oldest land plant remains from Baltica2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 1, p. 16-21Article in journal (Refereed)
    Abstract [en]

    A palynological study of the Ordovician–Silurian boundary (Katian–Rhuddanian) succession in the Röstaånga-1 drillcore, southern Sweden, has been performed. The lithology is dominated by mudstone and graptolitic shale, with subordinate limestone, formed in the deeper marine halo of southernBaltica. The palynological assemblages are dominated by marine microfossils, mainly chitinozoans and acritarchs. Sparse but well-preserved cryptospores, including Tetrahedraletes medinensis, Tetrahedraletes grayii and Pseudodyadospora sp., were encountered in the Lindegård Formation (late Katian–early Hirnantian), with the oldest record just above the first appearance of the graptolite species Dicellograptus complanatus. This represents the earliest record of early land plant spores from Sweden and possibly also from Baltica and implies that land plants had migrated to the palaeocontinent Baltica by at least the Late Ordovician.

  • 2.
    Bergström, Jan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Hou, Xian-Guang
    Yunnan University, Kunming.
    Hålenius, Ulf
    Swedish Museum of Natural History, Department of Geology.
    Gut contents and feeding in the Cambrian arthropod Naraoia2007In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, p. 71-76Article in journal (Refereed)
  • 3.
    Holtstam, Dan
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Söderhielm, Johan
    Sveriges Geologiska Undersökning.
    An 18th century find of an erratic lazulite-andalusite-quartz boulder in Södermanland, Sweden, and its implications2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 141, no 3, p. 216-221Article in journal (Refereed)
    Abstract [en]

    At some point in the 1750s, a jeweller-apprentice by the name Jacob Hässelgren found an erratic bouldernext to the Eskilstuna country road in the neighbourhood of Ärla in Södermanland. It contained a deep bluemass of lazulite, at the time an unknown mineral. Pieces of the find eventually reached Daniel Tilas, TorbernBergman and Axel Fredrik Cronstedt ˗ renowned natural scientists in Sweden ˗ but no detailed studies of thematerial seem to have been carried out by them. Two fragments of the original boulder are still preserved,and a recent examination shows them to consist of mainly lazulite, andalusite, quartz, pyrophyllite, augeliteand svanbergite. The average composition of lazulite is Mg0.700Fe2+0.261Mn0.003Al1.954Fe3+0.017 P2.031O8(OH)2.The mineral assemblage is characteristic of known occurrences of phosphate-Al silicate-quartz appearingalong the Protogine Zone in southern Sweden. Transportation of the boulder from its source rock, likely tobe located somewhere along the Protogine Zone, ought to have occurred in connection with the developmentof the Fennoscandian ice sheet during the final Weichselian deglaciation, and the material waspossibly discharged from floating ice on the Yoldia Sea.

  • 4.
    Johansson, Åke
    Swedish Museum of Natural History, Department of Geology.
    A refined U-Pb age for the Stockholm granite at Frescati, east-central Sweden2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 141, no 1, p. 40-47Article in journal (Refereed)
    Abstract [en]

    A sample of fine-grained grey Stockholm granite from the Frescati area just north of central Stockholm, east-central Sweden, earlier dated to 1803 +23/−19 Ma by the U-Pb zircon method using TIMS on multigrain fractions, has been reanalyzed using the Nordsim ion microprobe. The new age obtained, 1792±4 Ma, is more precise, and replaces the earlier highly discordant date. It agrees well with other ages for the formation of the Stockholm-type granites and related pegmatites, indicating an age of around 1.79 Ga for this late-orogenic Svecofennian granite magmatism. The Stockholm granite thus formed toward the end of the 1.83–1.79 Ga late Svecofennian metamorphic phase, and crosscuts earlier formed migmatitic gneiss structures in a brittle manner at the present-day level of exposure.

  • 5.
    Johansson, Åke
    Swedish Museum of Natural History, Department of Geology.
    U-Pb SIMS dating of some granitoids from eastern Blekinge, southern Sweden2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, no 3, p. 430-444Article in journal (Refereed)
    Abstract [en]

    Zircons from seven granitoids in eastern Blekinge have been dated using secondary ion mass spectrometry. The analyzed rocks include one Småland granitoid from north of the Småland-Blekinge Deformation Zone (SBDZ), two samples of megacrystic “Filipstad-type” granite from south of that zone, and one sample each of the “Småland-type” Rödeby, Almö, Tjurkö and Jämjö granites. The results yield a crystallization age of 1776 ± 6 Ma for the Småland granitoid, and crystallization ages between 1770 ± 4 and 1758 ± 6 Ma for the other granitoids, in most cases substantially older than previous TIMS ages. These data show that the “Småland-type” granitoids in eastern Blekinge are similar in age to the surrounding Tving granitoids, and the more felsic of them may represent late-stage differentiates belonging to the same magmatic suite. As the Tving granitoids show differences both in degree of deformation, in geochemistry and possibly in age, when compared with the Småland granitoids north of the SBDZ, it is suggested that these represent two separate but closely related igneous suites, which could both be included within a TIB-1 supersuite.

    The investigated zircons showed very limited signs of metamorphic overgrowths, and no metamorphic ages could be determined. However, the combined evidence from field observations combined with earlier U-Pb geochronology would suggest the presence of two separate metamorphic episodes in Blekinge, one in close connection with the formation of these rocks at 1.76 – 1.75 Ga, and one connected to the intrusion of the Karlshamn granitoid suite at around 1.45 Ga.

  • 6.
    Johansson, Åke
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Andersen, Tom
    Universitetet i Oslo.
    Simonsen, Siri L.
    Universitetet i Oslo.
    Hafnium isotope characteristics of late Palaeoproterozoic magmatic rocks from Blekinge, southeast Sweden: possible correlation of small-scale Hf and Nd isotope variations in zircon and whole-rocks.2015In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 137, no 1, p. 74-82Article in journal (Refereed)
  • 7.
    Jonsson, Erik
    et al.
    Sveriges Geologiska Undersökning, Uppsala.
    Hålenius, Ulf
    Swedish Museum of Natural History, Department of Geology.
    Mn3+-bearing pargasite from the Långban Fe-Mn oxide mineralisation, Bergslagen, Sweden2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, p. 167-172Article in journal (Refereed)
  • 8.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology.
    Cameral deposits in Paleozoic cephalopods2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 40, p. 254-263Article in journal (Refereed)
    Abstract [en]

    Calcareous cameral deposits have been described in several orthocerid and actinocerid nautiloids. According to the prevailing hypothesis, they were secreted during the lifetime of the animal, either by living tissues in the shell chambers, or by precipitation from the cameral liquid. In the present paper, cameral deposits are described in three species of Carboniferous orthocerid-like coleoid (Order Colorthocerida) from USA. The shell walls and septa in these coleoids are very thin and poorly calcified. In one half of the population of the three species, the septa are completely fragmented and there are no cameral deposits. In the other half of the population, the septa are partially fractioned and their surfaces are covered by welldeveloped cameral deposits. In contrast to the septa, the cameral deposits do not show any fractioning. To explain the origin of the cameral deposits, the following hypothetical scenario is the most realistic. After the death of the animals, the shells were accumulated on the sea floor and in one half of the population the septa became fully fractioned by the hydrostatic pressure. In shells of another half of the population, the septa were only partially fractioned. The calcifying bacteria entered the chambers of the dead shells through the porous connecting rings and gave rise to the cameral deposits.

  • 9.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology. Naturhistoriska Riksmuseet.
    Characterization of two new superorders Nautilosiphonata and Calciosiphonata and a new order Cyrtocerinida of the subclass Nautiloidea: siphuncular structure in the Ordovician nautiloid Bathmocerass (Cerphalopoda)2015In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 137, no 3, p. 164-174Article in journal (Refereed)
    Abstract [en]

    Based on differences in the siphuncular structures, the subclass Nautiloidea is divided into two new superorders: Nautilosiphonata and Calciosiphonata. The first superorder is characterized by the nautilus-type of connecting rings, and the second superorder by calcified-perforate type of the connecting rings. A new order Cyrtocerinida is erected for the families Bathmoceratidae, Cyrtocerinidae and Eothinoceratidae, previously included in the order Ellesmeroceratida. The siphuncular structure in the Ordovician nautiloid Bathmocerasholmi n. sp. is described. It is characterized by (1) connecting rings that are composed of an outer, calcareous, spherulitic–prismatic layer and an inner, fibrous, chitinous layer, and (2) prominent siphuncular ridges that originate from the inner surfaces of the connecting rings. The structure of the siphuncular ridges in Bathmoceras is compared with that of the actinosiphonate lamellae in the Silurian oncocerid nautiloid Octamerella.

  • 10.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology. Naturhistoriska Riksmuseet.
    Siphuncular structure in the extant Spirula and in other coleoids (Cephalopoda)2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 139, no 2, p. 129-139Article in journal (Refereed)
    Abstract [en]

    The shell wall in Spirula is composed of prismatic layers, whereas the septa consist of lamello-fibrillar nacre. The septal neck is holochoanitic and consists of two calcareous layers: the outer lamello-fibrillar nacreous layer that continues from the septum, and the inner pillar layer that covers the inner surface of the septal neck. The pillar layer probably is a structurally modified simple prisma layer that covers the inner surface of the septal neck in Nautilus. The pillars have a complicated crystalline structure and contain high amount of chitinous substance. The interspaces between the pillars probably are traversed horizontally by numerous chitinous membranes like in the cuttlebone chambers in Sepia. The connecting ring is composed of similar two layers as that in the extant Nautilus: the outer spherulitic–prismatic layer and the inner chitinous layer. The spherulitic–prismatic layer takes its origin on the outer surface of the septal neck, whereas the inner chitinous layer is the non-calcified continuation of the lamello-fibrillar nacreous layer of the septal neck. The siphuncular structure in Spirula is compared with that in the extant Nautilus, fossil nautilosiphonate nautiloids, and five taxa of coleoids.

  • 11.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology.
    Siphuncular structure in the Jurassic belemnitid Megateuthis (Cephalopoda, Coleoidea)2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, p. 1-8Article in journal (Refereed)
  • 12.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology. Naturhistoriska Riksmuseet.
    Siphuncular structures in Calciosiphonate nautiloid orders Actinocerida, Orthocerida and Barrandeocerida (Cephalopoda).2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, p. 295-305Article in journal (Refereed)
  • 13.
    Mutvei, Harry
    Swedish Museum of Natural History, Department of Paleobiology. Naturhistoriska Riksmuseet.
    The new order Mixosiphonata (Cephalopoda: Nautiloidea) and related taxa; estimations of habitat depth based on shell structure2017In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 139, p. 219-232Article in journal (Refereed)
    Abstract [en]

    The new order Mixosiphonata is characterized by its siphuncular structure. The order contains the ectocochleate cephalopods Boggyoceras centrale n. gen. et n. sp. (Carboniferous) and Zhuravlevia insperata (Cretaceous); both are orthocones. The bactritoid-like coleoid Ctenobactrites lesliensis (Carboniferous) has a similar siphuncular structure and is therefore, provisionally included in this new order. In the new order Mixosiphonata, the proximal part of the septal neck has the same structure as the septum from which it originates, whereas the entire distal part is composed of prismatic and spherulitic layers embedded into a chitinous substance. Also the connecting ring consists of prisms and spherulites embedded into chitinous substance, but the calcareous elements are smaller than those in the distal part of the septal neck. The structure of the connecting ring and septal neck differs from the 13 types of siphuncular structures in nautiloids, ammonoids and coleoids that are currently known. The siphuncular structure in the Ordovician cephalopod Bactroceras avus is described and compared with that in the mixosiphonates. The shell strength indexes derived from the extant Nautilus cannot be used for estimations of habitat depth in most, if not all, known externally shelled cephalopods because in the fossil cephalopods the siphuncular structures are different from that of extant Nautilus, and therefore, the mechanical strength of the siphuncles in the fossil shells and Nautilus shell is not comparable.

  • 14.
    Mutvei, Harry
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Mapes, Royal H.
    bAmerican Museum of Natural History, New York, NY, USA.
    Carboniferous coleoids with mixed coleoid-orthocerid characteristics: a new light oncephalopod evolution2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 140, p. 11-24Article in journal (Refereed)
    Abstract [en]

    Orthocerid-like coleoids with mixed orthocerid-coleoid characteristics are described for the first time from the Carboniferous of USA. The appearance of these coleoids represents transitional morphology between the orthoconic nautiloid and coleoid lineages. This transitional state is based on the new genus Colorthoceras n. gen. with three assigned new species (C. inflata n. sp., C. tubulata n. sp. and C. concavus n. sp.) in the new family Colorthoceridae of the new order Colorthocerida. Orthocerid nautiloid characteristics include a longiconic phragmocone with a well-developed body chamber, and a central, sub-central or sub-ventral siphuncle with endosiphuncular deposits. The shell wall in the new order Colorthocerida is characterized by the coleoid characteristics of a lack of the nacreous layer, with a high content of chitin that created a somewhat semi-elastic shell. The connecting rings are uni-layered, directly continuous from the septal neck, and have a mixed chitinous-calcareous composition similar to that in order Mixosiphonata. The shell wall structure in these unique orthocerid-like coleoids is similar to that in the previously described Carboniferous bactritoid-like coleoids. The evolution of these coleoid characteristics appears to represent an unsuccessful evolutionary experiment, as the diversity of this nautiloid lineage was in gradual decline in the Upper Paleozoic.

  • 15.
    Mörs, Thomas
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Liu, Liping
    Swedish Museum of Natural History, Department of Paleobiology.
    Hagström, Jonas
    Swedish Museum of Natural History, Department of Paleobiology.
    A Miocene tetraconodontine (Suidae, Mammalia) from Falkenberg (Halland, Sweden)2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, p. 77-81Article in journal (Refereed)
  • 16.
    Rubinstein, Claudia
    et al.
    Department of Paleopalynology, IANIGLA, CCT CONICET Mendoza.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Baltica cradle of early land plants? Oldest record of trilete spores and diversecryptospore assemblages; evidence from Ordovician successions of Sweden2019In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 141, p. 181-190Article in journal (Refereed)
    Abstract [en]

    The origin of land plants is one of the most important evolutionary events in Earth’s history. The mode and timing of the terrestrialization of plants remains debated and previous data indicate Gondwana to be the center of land-plant radiation at ~ 470–460 Ma. Here we present the oldest occurrences of trilete spores, probably the earliest traces of vascular land plants yet recorded. The spores occur in Ordovician, Sandbian (455 million years old) successions in central Sweden, once part of the paleocontinent Baltica. These strata are independently dated by marine microfossils (conodonts) and 206Pb/238U dating of volcanic ash deposits. Our discovery extends the record of trilete spores globally by ~8 million years, and for Baltica by ~25 million years. Additionally, cryptospore assemblages are identified revealing a diverse and stable mid-Ordovician (Darriwilian: ~ 460 Ma) vegetation of free-sporing plants. The formation of regolith substrates on land as a consequence of permanent plant cover must in turn have affected the marine biota. We link these early land plant spore occurrences to the extensive, nutrient-rich volcanic ash deposits and propose Baltica as the possible original region of the radiation of early land plants.

  • 17. Shumlyanskyy, Leonid
    et al.
    Ernst, Richard
    Söderlund, Ulf
    Lund University.
    Billström, Kjell
    Swedish Museum of Natural History, Department of Geology.
    Mitrokhin, O
    Tsymbal, Stephan
    New U–Pb ages for mafic dykes in the Northwestern region of the Ukrainian shield: coeval tholeiitic and jotunitic magmatism2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, p. 79-85Article in journal (Refereed)
    Abstract [en]

    The palaeoproterozoic Northwestern region of the Ukrainian shield hosts two compositional types of mafic dykes and associated magmatism that intruded at c. 1800–1760 Ma: (1) high-Ni dolerite dykes and layered intrusions of tholeiitic affinity and (2) high-Ti dolerite dykes of jotunitic affinity associated with anorthosite–mangerite–charnockite–granite (AMCG) suites. The jotunitic dykes represent initial melts for basic rocks of the Korosten AMCG plutonic complex, whereas tholeiitic dykes may reflect emplacement of a mantle plume and formation of a large igneous province (LIP). New U–Pb baddeleyite ages indicate that both compositional types can be coeval: the jotunitic Rudnya Bazarska dyke was emplaced at 1793 ・} 3 Ma, and the Zamyslovychi tholeiitic dolerite dyke at 1789 +/-9 Ma. In our model, the mantle plume-derived tholeiitic melts (underplate) supplied heat required for melting of the mafic lower crust and the production of jotunitic melts. As formation of the jotunite melts requires pressures in the range 10–13 kbar, either a thickened crust is needed or the lower crust must be subducted, or downthrusted, into the mantle. Alternatively, emplacement and ponding of large volume of tholeiitic melts might cause delamination of the lower crust, its sinking into the mantle, and further fusion to produce jotunitic melts.

  • 18. Shumlyanskyy, Leonid
    et al.
    Mitrokhin, O
    Billström, Kjell
    Swedish Museum of Natural History, Department of Geology.
    Ernst, Richard
    Vishnevska, Eugenia
    Tsymbal, Stepan
    Cuney, Michel
    Soesoo, Alvar
    The ca. 1.8 Ga mantle plume related magmatism of the central part of the Ukrainian shield2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, p. 86-101Article in journal (Refereed)
    Abstract [en]

    Palaeoproterozoic (ca. 1.8 Ga) mafic and ultramafic dykes are widely distributed within thewhole Sarmatian segment of the East-European craton. This paper focuses on new geochronological,geochemicaland isotope data obtained for mafic and ultramafic dykes of the Ingul terrain. Geochronological data available for these dykes indicate ages around 1800 Ma. We provide a new U–Pb zircon age of1810 ± 15 Ma obtained for a dolerite dyke in the Kirovograd area. Geochemical and petrographical dataallow identification of three groups of dykes: (1) kimberlites, (2) high-Mg# subalkaline rocks (picrite,camptonite, subalkaline dolerite etc.) and (3) tholeiite dolerite. Rocks of these groups were probably derived from different sources. Eps-Nd1800 values of studied rocks vary from 0.7 to 2.8. The highest values were obtained for mantle xenoliths and their kimberlite host (Eps-Nd1800 = 2.5–2.8). Rb–Sr data yield aregressionage of 1729 ± 20 Ma with an initial 87Sr/86Sr = 0.70366 ± 41 (MSWD = 10.8). The whole-rock lead isotope data scatter, but data for sub-groups of samples can tentatively be fitted to parallel 1.8 Ga isochrons.The geochemical data indicate rocks to have formed by partial melting and the degree of melting is thought to be a function of formation depth, the latter ranging from sub-lithospheric to lower crustal levels; we assume that melting was caused by a mantle plume. Dyking in the Ingul terrain was closely associated in time and space with metasomatic albitites that host numerous economic U deposits.

  • 19. Shumlyanskyy, Leonid
    et al.
    Nosova, Anna
    Billström, Kjell
    Swedish Museum of Natural History, Department of Geology.
    Söderlund, Ulf
    Lund University.
    Andréasson, Per-Gunnar
    Lund University.
    Kuzmenkova, Oksana
    The U–Pb zircon and baddeleyite ages of the Neoproterozoic Volyn Large Igneous Province: implication for the age of the magmatism and the nature of a crustal contaminant2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, p. 17-30Article in journal (Refereed)
    Abstract [en]

    The Volyn continental flood basalt province is situated on the western margin of the East European platform and constitutes a significant portion of the passive continental margin sequence formed along the Trans-European Suture Zone in response to Rodinia break-up in the Neoproterozoic. In Ukraine, the volcanogenic sequence is subdivided into suites called Zabolottya, Babyne and Ratne,which together with the lowermost terrigeneous Gorbashy suite comprise the Volyn series. Magmatic zircons from one high-Ti basalt sample yielded an age of 573 ± 14 Ma, whereas grains isolated from a rhyolitic dacite yielded an age of 571 ± 13 Ma. Baddeleyite from the olivine dolerite sample gave an older 206Pb/238U age of 626 ± 17 Ma, whereas the 207Pb/206Pb weighted average age of 567 ± 61 Ma is close to the zircon ages. Zircons separated from the other basaltic samples are much older and crystallized at c. 1290, 1470, 1820-1860, 1930-2050 and 2660 Ma. Ages in the 1820-1860 and 1930-2050 Ma time spans correspond to the ages of the Precambrian basement that underlies the Volyn province. However, the sources for the 1290, 1470 and 2660 Ma zircons are unknown, and these zircons must have been derivedfrom more distal areas.

  • 20. Siliauskas, Laurynas
    et al.
    Skridlaite, Grazina
    Baginski, Bogusław
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Prusinskiene, Sabina
    What the ca. 1.83 Ga gedrite-cordierite schists in the crystalline basement of Lithuania tell us about the late Palaeoproterozoic accretion of the East European Craton2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 140, no 4, p. 332-344Article in journal (Refereed)
    Abstract [en]

    ABSTRACTIn the western East European Craton (EEC), southern Lithuania, a suite of fine-grained, thinly bedded rocks of unusual composition has been shown to have originally comprised intermediate and felsic volcanic rocks. They extruded at ca. 1.83 Ga and were hydrothermally altered prior to metamorphism, which converted them into garnet-, gedrite-, anthophyllite-, staurolite- and cordierite-bearing schists. After the rocks have experienced a 630°C and 7 kbar metamorphism, they were uplifted to 15 km (5 kbar) probably at ca. 1.73 Ga. They were reheated to 640°C at ca. 1.50 Ga (monazite age). The monazite age of ca. 1.50 Ga is coeval with the emplacement of the neighboring 1.50 Ga Anorthosite-Mangerite-Charnockite-Granite (AMCG) Mazury complex. The ca. 1.83 Ga volcanic suites in Lithuania and northern Poland, together with the Oskarshamn-Jönköping belt (OJB) in south-central Sweden, may belong to the same chain of volcanic island arcs, and thus provide information on the evolution of the entire western EEC. The ca. 1.50 Ga metamorphic reworking and the replacement of the Mazury AMCG suite may have been triggered by the Danopolonian orogeny further west and, at a larger scale, accretion of the continental margin of Columbia.

  • 21. Sjöqvist, Axel
    et al.
    Lindgren, Paula
    Sturkell, Erik
    Hogmalm, K
    Broman, Curt
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Lee, M
    Shock metamorphism and hydrothermal alteration of mafic impact ejecta from the Lockne impact structure, Sweden2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863Article in journal (Refereed)
  • 22.
    Skovsted, Christian
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Ushatinskaya, Galina
    Holmer, Lars, E.
    Popov, Leonid, E.
    Kouchinsky, Artem
    Swedish Museum of Natural History, Department of Paleobiology.
    Taxonomy, morphology, shell structure and early ontogeny of Pelmanotreta nom. nov. from the lower Cambrian of Siberia2015In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 137, no 1, p. 1-8Article in journal (Refereed)
    Abstract [en]

    The new generic name Pelmanotreta is proposed under the provisions of the International Code of Zoological Nomenclature (ICZN) to replace Cryptotreta Pelman, 1977 (Brachiopoda), a junior homonym of Cryptotreta Blanc & Foote, 1961 (Arthropoda). This poorly known brachiopod genus and its type and only species, Pelmanotreta neguertchenensis (Pelman, 1977), from the early Cambrian of Siberia is redescribed. The family-level taxonomy of Pelmanotreta and other “cryptotretid” brachiopods is uncertain. In Pelmanotreta, dorsal valves vastly outnumber ventral valves in all collections but new specimens of the poorly known ventral valve reveal a possibly septate and poorly mineralized apical region. A prismatic hexagonal shell structure comparable to that of Salanygolina is described. P. neguertchenensis preserves the earliest known record of a larval shell in brachiopods.

  • 23.
    Topper, Timothy P.
    et al.
    Geologisk Museum, Statens Naturhistoriske Museum, Danmark.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    A new name for a classic Cambrian Swedish brachiopod, Tallatella undosa (Moberg)2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 3, p. 429-435Article in journal (Refereed)
    Abstract [en]

    The brachiopod originally described as Kuturgina undosa Moberg, 1892 from the early Cambrian (Cambrian Series 2, Stage 4) När Shale of Kalmarsund, Sweden, has experienced a long and turbulent history since the original description over 100 years ago. Uncertainties regarding key morphological characters have resulted in the species taxonomically hopping between genera until it wasrecently assigned to the poorly known genus Cryptotreta Pelman, 1977 and subsequently transferred to the problematic paterinate family Cryptotretidae. Despite members of this group representing the oldest brachiopods in the fossil record, they remain enigmatic, both taxonomically and phylogenetically. Theidentification of the brachiopod species from the När Shale as a cryptotretid means that this brachiopod was the first member of the family to be discovered, yet its systematic position is far from certain. Examination of type material in addition to supplementary material acquired from the Skäggenäs Peninsula, Sweden, has elucidated many of the previous ambiguous morphological characteristics of the species. The new morphological information acquired here has resulted in the erection of a new paterinate genus, Tallatella gen. nov., to accommodate the Swedish material previously described as Cryptotreta undosa.

  • 24. Topper, Timothy
    et al.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    A new name for a classic Cambrian Swedish brachiopod, Tallatella undosa (Moberg)2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 4, p. 429-435Article in journal (Refereed)
    Abstract [en]

    The brachiopod originally described as Kuturgina undosa Moberg, 1892 from the early Cambrian (Cambrian Series 2, Stage 4) Nar Shale of Kalmarsund, Sweden, has experienced a long and turbulent history since the original description over 100 years ago. Uncertainties regarding key morphological characters have resulted in the species taxonomically hopping between genera until it was recently assigned to the poorly known genus Cryptotreta Pelman, 1977 and subsequently transferred to the problematic paterinate family Cryptotretidae. Despite members of this group representing the oldest brachiopods in the fossil record, they remain enigmatic, both taxonomically and phylogenetically. The identification of the brachiopod species from the Nar Shale as a cryptotretid means that this brachiopod was the first member of the family to be discovered, yet its systematic position is far from certain. Examination of type material in addition to supplementary material acquired from the Skaggenas Peninsula, Sweden, has elucidated many of the previous ambiguous morphological characteristics of the species. The new morphological information acquired here has resulted in the erection of a new paterinate genus, Tallatella gen. nov., to accommodate the Swedish material previously described as Cryptotreta undosa.

  • 25.
    Vajda, Vivi
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Calner, Mikael
    Ahlberg, Anders
    Palynostratigraphy of dinosaur footprint-bearing deposits from theTriassic–Jurassic boundary interval of Sweden2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, p. 120-130Article in journal (Refereed)
    Abstract [en]

    The Triassic–Jurassic boundary (c. 200 Ma) marks one of the five largest Phanerozoic mass extinction events and is characterized by a major turnover in biotas. A palynological study of sedimentary rock slabs bearing dinosaur footprints from Rhaeto–Hettangian strata of Skåne, Sweden was carried out. The theropod dinosaur footprints (Kayentapus soltykovensis) derive from the southern part of the abandoned Vallåkra quarry (Höganäs Formation) and were originally dated as earliest Jurassic (Hettangian) based on lithostratigraphy. Our results reveal that two of the footprints are correlative with the latest Triassic (latest Rhaetian) disaster zone typified by a high abundance of the enigmatic gymnosperm pollen Ricciisporites tuberculatus and Perinopollenites elatoides together with the key taxon Limbosporites lundbladii and fern spores. Two footprints are dated to correlate with the Transitional Spore-spike Interval. One footprint is interpreted as Hettangian in age based on the relatively high abundance of Pinuspollenites spp. together with the presence of the key taxa Retitriletes semimuris and Zebrasporites intercriptus. Our new palynological study suggests that the Kayentapus ichnogenus already appeared in the end of Triassic, and our study highlights the use of palynology as a powerful tool to date historical collections of fossils in museums, universities and elsewhere. The Hettangian footprint reflects a marine influence while all other studied ichnofossil specimens occur in non-marine (floodplain and delta interdistributary) sediments. The sediments associated with the Hettangian footprint include a significant proportion of charcoal transported from land after wildfires. The Rhaeto–Hettangian vegetation was otherwise characterized by multi-storey gymnosperm–pteridophyte communities.

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