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  • 1.
    Agić, Heda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Moczydłowska, Małgorzata
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Canfield, Donald
    University of Southern Denmark .
    Reproductive cyst and operculum formation in the Cambrian-Ordovician galeate-plexus microfossils2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, no 2, p. 278-294Article in journal (Refereed)
    Abstract [en]

    Unicellular organic-walled microfossils from the Cambrian-Ordovician transition in Estonia (ca. 490-480 million years ago) exhibit rare characters reflecting their function as reproductive algal cysts. The studied assemblages record the evolutionary history of phytoplankton in the early Paleozoic Era: novel morphologies appearing through the Cambrian and subsequently diversifying in the Ordovician. Well preserved specimens were extracted following a standard palynological method and studied by light transmitted microscopy. The galeate plexus acritarchs Caldariola, Priscogalea and Stelliferidium have revealed exceptionally preserved morphological elements and a rare structure among both fossil and extant protists – an opening with operculum (lid) in reproductive cysts, in addition to lavish vesicle ornamentation and sculpture. Analogous morphology is observed in the living dasycladalean alga Acetabularia (Chlorophyta), which possesses an intrinsic lid-forming apparatus used during organism’s reproductive stage. Based on the observations on the fossil material and studies on the Acetabularia lid-formation, we propose a model of operculum formation in the galeate plexus microorganisms. Due to strong morphological and ecological similarities between galeate fossils and dasycladalean cysts, and the antiquity of this algal order, galeates may be positioned within green algae, more specifically Dasycladales. Unique morphology of the operculum-bearing microbiota would have required a high degree of intracellular complexity for its development, suggesting that advanced intracellular machinery was present already in the early Paleozoic phytoplankton. Additionally, minute prasinophyte microfossils Reticella corrugata  are reported for the first time in the Upper Cambrian strata. 

  • 2.
    Andersson, Stefan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics. Univ Helsinki, Dept Geosci & Geog, FI-00014 Helsinki, Finland.
    Jonsson, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics. Geol Survey Sweden, Dept Mineral Resources, Uppsala, Sweden.
    Högdahl, Karin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Metamorphism and deformation of a Palaeoproterozoic polymetallic sulphide-oxide mineralisation: Hornkullen, Bergslagen, Sweden2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, no 3, p. 410-423Article in journal (Refereed)
    Abstract [en]

    The Hornkullen mineralisation is situated in the westernmost part of the Bergslagen ore province, south-central Sweden. Here, polymetallic sulphides and oxides are hosted by an inlier of Svecofennian, c. 1.9Ga skarn-bearing metavolcanic units, enclosed in the c. 1.8Ga Filipstad granite belonging to the Transscandinavian Igneous Belt. The Ag- and Au-bearing mineralisation is dominated by veins and impregnations of magnetite, pyrrhotite, galena, chalcopyrite and arsenopyrite with subordinate pyrite, sphalerite, ilmenite, lollingite, Pb-Fe-Ag-Cu-Sb sulphosalts and rare gudmundite, pentlandite and molybdenite. Overall, a detailed textural and mineralogical study of the ore assemblages suggests significant deformation and remobilisation at high temperature, which is corroborated by sulphide geothermobarometry. The arsenopyrite geothermometer yields an average temperature of c. 525 degrees C, which is likely to be the result of metamorphic re-equilibration. Sphalerite geobarometry gives peak pressures of c. 300-400MPa, albeit with caveats. The combined observations suggest that the present mineralogical and textural nature of the ore assemblages at Hornkullen is primarily related to remobilisation during Svecokarelian regional metamorphism of a pre-existing, most likely syn-volcanic mineralisation. This scenario is likely to be applicable to many other Svecofennian metasupracrustal-hosted deposits in the Bergslagen ore province.

  • 3.
    Arvestål, Emma
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Cyrtograptids from the Telychian (upper Llandovery) of Kinnekulle Mountain, southern Sweden2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 1, p. 45-56Article in journal (Refereed)
    Abstract [en]

    The late Llandovery graptolite fauna of the Retiolites Shales on Kinnekulle Mountain in the province of Västergötland has long been known but never illustrated or studied in detail. New collections of graptolites from an interval at the very top of the exposed succession confirm previous reports of cyrtograptids, which make the shales on Kinnekulle the youngest preserved Palaeozoic rocks in the area. The co-occurrence of Oktavites spiralis and Cyrtograptus lapworthi constrains the strata to the lower lapworthi Biozone of the upper Telychian. The associated graptolite fauna comprises numerous monograptids and Retiolites angustidens as well as Cyrtograptus kinnekullensis n. sp., characterised by its open coiling and the presence of a second-order cladium on the second thecal cladium. This early occurrence of a cyrtograptid species with a second-order cladium on Baltica matches evolutionary patterns observed in Laurentia, suggesting that the ability to grow cladia of both first and higher order evolved approximately, synchronously and at the very beginning of cyrtograptid evolution.

  • 4.
    Bark, Glenn
    et al.
    Luleå tekniska universitet, Geovetenskap och miljöteknik.
    Broman, Curt
    Stockholms Universitet.
    Weihed, Pär
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Fluid chemistry of the Palaeoproterozoic Fäboliden hypozonal orogenic gold deposit, northern Sweden: evidence from fluid inclusions2007In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, no 3, p. 197-210Article in journal (Refereed)
    Abstract [en]

    A new ore province, the Gold Line, southwest of the Skellefte District, northern Sweden, is currently under exploration. The largest known deposit in the Gold Line is the hypozonal Fäboliden orogenic gold deposit. The mineralization is hosted by arsenopyrite-bearing quartz veins, within a steep shear zone in amphibolite facies metagreywacke host rocks. Gold occur in fractures and as intergrowths in arsenopyrite-löllingite, and as free grains in the silicate matrix of the host rock. The hydrothermal mineral assemblage in the proximal alteration zone is diopside, calcic amphibole, biotite, and minor andalusite and tourmaline. Primary fluid inclusions in the Fäboliden quartz veins show a CO2-CH4 or a H2S (±CH4) composition (the latter recognized for the first time in a Swedish ore deposit). The primary fluid inclusions are associated with arsenopyrite-löllingite (+gold) and the CO2-CH4 fluid was also involved in precipitation of graphite. A prevalence of carbonic over aqueous fluid inclusions is characteristic for a number of hypozonal high-temperature orogenic gold deposits. The Fäboliden deposit, thus, shows fluid compositions similar to other hypozonal orogenic gold deposits. The proposed main mechanism for precipitation of gold from the fluids, is a mixing between H2S-rich and H2O?-CO2±CH4 fluids. Fluid inclusion data indicate arsenopyrite-löllingite and graphite deposition at a pressure condition of about 4 kbar. Graphite thermometry indicates maximum temperatures of 520-560°C for the hydrothermal alteration at Fäboliden, suggesting that at least the late stages of the mineralizing event took place shortly after peak-metamorphism in the area, i.e. at c. 1.80 Ga.

  • 5. Bassett-Butt, Lewis
    Systematics, biostratigraphy and biogeography of brachiopods and other fossils from the Middle Cambrian Nelson Limestone, Antarctica2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, no 3, p. 377-392Article in journal (Refereed)
    Abstract [en]

    An assemblage dominated by acrotretid brachiopods (Prototreta millsi Brock and Percival, 2006) is described from the Nelson Limestone of the Transantarctic Mountains, Antarctica. The formation also includes paterinids (Micromitra sp. cf. M. nerranubawu Kruse, 1990 and Dictyonina australis Roberts, 1990), lingulids (Oepikites haimantensis Reed, 1910)and acrothelids (Acrothele sp. cf. A. vertex Reed, 1910). The macrofauna also contains orthids (Diraphora dyunyin Kruse, 1990). The associated fauna include sponge spicules present in vast abundance. Other recognisable small shelly fossils (including chancelloriids and hyolithelminths) make up a small section of the fauna. Trilobites (including Nelsonia schesis Palmer and Gatehouse, 1972 and Solenopleura pruina Palmer and Gatehouse, 1972) belong to taxa previously described from the Nelson Limestone and support the Drumianage proposed for the formation. Palaeobiogeographic analysis indicates that the brachiopod fauna corroborates previously described strong links with Australasia and also suggests a strong link to Indian material, corroborating previous evidence for an East Gondwanan faunal province in the Middle Cambrian.

  • 6. Bauert, Heikki
    et al.
    Isozaki, Yukio
    Holmer, Lars Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Aoki, Kazumasa
    Sakata, Shuhei
    Hirata, Takafumi
    New U-Pb zircon ages of the Sandbian (Upper Ordovician) "Big K-bentonite" in Baltoscandia (Estonia and Sweden) by LA-ICPMS2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 1, p. 30-33Article in journal (Refereed)
    Abstract [en]

    Oscillatory-zoned euhedral single zircons from the upper Sandbian (Upper Ordovician) Kinnekulle K-bentonite exposed in a hillock at Paaskula in Estonia and at the type locality on Mt Kinnekulle in Sweden were dated in a grain-by-grain manner by laser ablation-inductively coupled plasma mass spectrometer. The U-Pb (weighed mean) ages of the 25 grains from Mt Kinnekulle and 24 grains from Paaskula are 453.4 +/- 6.6 and 454.9 +/- 4.9Ma, respectively. This study provides the first ca. 454Ma (late Sandbian) age for the Ordovician K-bentonite in northern Estonia and confirmed its correlation with the type Kinnekulle bed across the Baltic Sea.

  • 7.
    Berg-Madsen, Vivianne
    et al.
    Uppsala University, Music and Museums, Museum of Evolution.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    The Bromell fossil collection at Uppsala University, Sweden: its history and the people behind it2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 1, p. 3-17Article in journal (Refereed)
    Abstract [en]

    Remains of 17(th) century cabinets of curiosity collections are held at the Museum of Evolution, Uppsala University, Sweden. Some of the oldest date back to the 1650s, and were included in the collection of Archiater, i.e. physician to the Crown, von Bromell (1679-1731). He is also known for publishing the first series of papers in Sweden to exclusively deal with palaeontology. Throughout his life he acquired specimens by collecting, buying or receiving in exchange to add to those he inherited from his father Olaus Bromelius, a famous botanist and physician. Information on the labels gives a glimpse of his network of friends, colleagues and fellow collectors, such as Kilian Stobaeus, Lars Roberg, Emanuel Swedenborg, Elias Brenner and Johan Dobelius. When Bromell died, his vast collections of books, coins, furniture, conchs, stuffed animals, minerals and fossils were sold off. The minerals and fossils were split up and owned by various persons during the following century. Parts owned by A. Lagerberg between the years 1746 and 1776 were bought in 1796 by Johan Afzelius and donated to Uppsala University at his death. Fossils and minerals earlier described by Bromell were in the care of The Royal Society of Science in Uppsala at least by 1791. Through the Institute of Geology, fossils accumulated over the centuries at Uppsala University eventually came together under the same roof in 1932, under professor Carl Wiman's care at the then newly erected Palaeontology museum building. Today, about 300 fossils from the Bromell collection are preserved at the museum.

  • 8.
    Berg-Madsen, Vivianne
    et al.
    Uppsala University, Music and Museums, Museum of Evolution.
    Valent, Martin
    Natl Museum, Dept Palaeontol, Cirkusova, Horni Pocernice, Czech Republic.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    An orthothecid hyolith with a digestive tract from the early Cambrian of Bornholm, Denmark2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 140, no 1, p. 25-37Article in journal (Refereed)
    Abstract [en]

    The hyolith assemblage from the early Cambrian of Bornholm, Denmark, shows a higher diversity than contemporary assemblages in Baltoscandia. The most common species in the Green Shales (Laesa Formation, Norretorp Member, Cambrian Stage 3), is Hyolithes [=Hyolithus] (Orthotheca) johnstrupi Holm, 1893. A specimen of this species shows a well-preserved and almost complete digestive tract, folded into an approximately 22mm long chevron-like structure comprised of at least 20 arcuate loops on the ventral side and a flattened, gently sinuous to straight anal tube on the dorsal side. The thin, phosphatic outer shell layer of the conch is crushed under the digestive tract due to compaction while the digestive tract is preserved in three dimensions and appears undisturbed. The shape of the digestive tract is similar to that of the middle Cambrian Guduguwan hardmani (Etheridge) from Australia and the lower Cambrian specimens from Russia described by Mekova & Sysoev. The Danish specimen is probably an adult, lending support to the idea that the orthothecid digestive tract becomes more complex during ontogeny. Hyolithus (Orthotheca) johnstrupi is revised and here referred to Circotheca Sysoev, 1958.

  • 9.
    Björklund, Lennart
    et al.
    Gothenburg University.
    Weihed, Pär
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences. Luleå tekniska universitet.
    Geochemistry and tectonic setting of the Orvar Hill mafic volcanic rocks of the Tiveden area, south-central Sweden1997In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 119, no 2, p. 127-134Article in journal (Refereed)
    Abstract [en]

    The Orvar Hill formation in Tiveden, south-central Sweden, constitutes a unique low-strain window of well preserved Svecofennian mafic volcanic rocks on the southwestern border of the Svecokarelian orogen. The area can be considered as the southwestern border of the Bergslagen region of the Svecokarelian orogen. The Orvar Hill formation consists of coherent pillowed and non-pillowed basalts alternating with mafic volcaniclastic racks in the lower part of the Lindberga supracrustal succession. Only minor felsic volcanic rocks occur in the upper part. Quartz-bearing metagreywackes comprise the top part of the Lindberga supracrustal succession. Geochemistry of lavas and volcaniclastic rocks suggests that the Orvar Hill mafic volcanic rocks were emplaced in a volcanic-are setting. This demonstrates that the Tiveden supracrustal units probably formed in response to volcanism related to subduction. The Tiveden area may thus represent a 1.89 Ga primitive, sediment-starved volcanic are at the margin of the continental volcanic are of the Bergslagen district. The relationship between Tiveden and Bergslagen at the time of formation is not clear and Tiveden may represent a remnant of an are that accreted to a continent at c. 1.88-1.86 Ga.

  • 10.
    Bogolepova, Olga
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Institute for Russian and Eurasian Studies.
    Donovan, Stephen K.
    Harper, David A. T.
    Suyarkova, Anna A.
    Yakupov, Rustem
    Gubanov, Alexander P.
    Uppsala University, Music and Museums, Museum of Evolution.
    New records of brachiopods and crinoids from the Silurian (Wenlock) of the southern Urals, Russia2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863Article in journal (Refereed)
    Abstract [en]

    Crinoids and brachiopods are described from the Silurian Uzyan Formation of the Zilair Zone in the southern Urals. The occurrence of the graptolites Coronograptus praedeubeli suggests a late Homerian (Wenlock) age for the strata. A new disparid crinoid, Cicerocrinus gracilis Donovan sp. nov., is the oldest known member of this genus. It has a long, flexible and homeomorphic column, and a tall bryozoan palaeontology terminology (IBr2) (second primibrachial) axillary. All species of Cicerocrinus described previously have been limited to the Ludlow of the British Isles, Sweden and Estonia, and the Pridoli of Estonia. The poorly preserved brachiopod fauna is represented by small atrypid (Atrypa? sp.) and dalmanellid brachiopods (Levenea? sp.). The reported assemblage generally inhabited deep-water environments.

  • 11.
    Chen, Donglei
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Blom, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Scale morphology and squamation of Andreolepis from the Late Silurian of Gotland, Sweden2011In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 133, no 1-2, p. 60-61p. 60-61Article in journal (Refereed)
  • 12. Clausen, Sebastien
    et al.
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Middle Cambrian echinoderm remains from the Henson Gletscher Formation of North Greenland2012In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 134, no 3, p. 173-200Article in journal (Refereed)
    Abstract [en]

    A Middle Cambrian (Series 3, Stage 5) echinoderm assemblage is described from the uppermost part of the Henson Gletscher Formation based on disarticulated material. This represents the first detailed echinoderm report from the Cambrian of North Greenland and one of the most diverse for that time. Recovered ossicles include a morphotype continuum between various biserial (brachiolar) and uniserial ("brachial") plates from pelmatozoan feeding appendages along with thecal insertion plates, pelmatozoan holomeric and the oldest known polymeric stem elements and holdfasts. Ambulacral flooring plates from two different edrioasteroids are also described. This assemblage illustrates a high plasticity and disparity in early echinoderm stem and feeding appendages, thereby placing stress on the usual definitions of blastozoans and crinozoans, generally considered as two pelmatozoan subphyla. Along with previous studies, it also raises the question as to how early echinoderms responded to the Agronomic Revolution (Substrate Revolution). Echinoderm remains first appear during Cambrian Series 2, Stage 3, well after the Substrate Revolution had affected the first few centimetres of substrate used by this low-level tiering animals to stabilize themselves. Contrary to previous ideas, it is suggested that echinoderms evolved quickly and in a nonlinear way in response to the abrupt establishment of a mosaic of substrate types during the early Cambrian. Finally, this study highlights the primary importance of disarticulated elements in the elucidation of the early evolution, diversity and disparity of the earliest echinoderms. Such elements are much more common and always appear earlier in the geological record than the complete articulated specimens on which echinoderm studies generally focus despite the taphonomic biases which often characterize their preservation.

  • 13.
    Dahlin, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Palaeoproterozoic metavolcanic and metasedimentary succession hostingthe Dannemora iron ore deposits, Bergslagen region, Sweden2012In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 134, no 2, p. 71-85Article in journal (Refereed)
    Abstract [en]

    The Dannemora supracrustal inlier is located in the north-eastern part of the Bergslagen regionin south-central Sweden and hosts the second largest iron ore deposit in the region. The metasupracrustalsuccession of the inlier consists of c. 1.9 Ga Palaeoproterozoic rocks that are mainly sub-alkaline, rhyoliticto dacitic, pyroclastic deposits, reworked pyroclastic deposits and metalimestone. It is c. 700–800-m thickand termed the Dannemora Formation. The formation is divided into lower and upper members and theformer is in turn subdivided into subunits 1 and 2. The great thickness of individual pyroclastic depositsindicates deposition within a caldera. The rocks show characteristics of a pyroclastic origin by containingabundant pumice, cuspate and Y-shaped former glass shards, and fragmented crystals of quartz andsubordinate feldspars. Scattered spherulites and lack of welding-compacted fiamme suggest that the lowermember was slightly welded, where as the upper member contains sericite-replaced glass shards withpreserved primary shapes indicating no welding. Undisturbed layers of ash-siltstone with normal gradingand fluid–escape structures are attributed to subaqueous deposition below storm wave base in the easternpart of the inlier, where as erosion channels and cross-bedding in some of the volcaniclastic deposits implydeposition and reworking above wave base in the central part of the inlier. Epidote spots, previouslyinterpreted as altered limestone fragments and an indicator for subaquatic deposition, are here reinterpretedas the result of selective alteration related to the intrusion of mafic dykes and to Ca release duringdolomitisation of limestone.

  • 14.
    Dahlin, peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Allen, R.
    Division of Geosciences and Environmental Engineering, Luleå University of Technology, Luleå, Sweden.
    Sjöström, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    The Palaeoproterozoic metavolcanic and metasedimentary succession hosting the Dannemora iron ore deposits, Bergslagen region, Sweden.2012In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 134, no 2, p. 71-85Article in journal (Refereed)
    Abstract [en]

    The Dannemora supracrustal inlier is located in the north-eastern part of the Bergslagen region in south-central Sweden and hosts the second largest iron ore deposit in the region. The metasupracrustal succession of the inlier consists of c. 1.9 Ga Palaeoproterozoic rocks that are mainly sub-alkaline, rhyolitic to dacitic, pyroclastic deposits, reworked pyroclastic deposits and metalimestone. It is c. 700–800-m thick and termed the Dannemora Formation. The formation is divided into lower and upper members and the former is in turn subdivided into subunits 1 and 2. The great thickness of individual pyroclastic deposits indicates deposition within a caldera. The rocks show characteristics of a pyroclastic origin by containing abundant pumice, cuspate and Y-shaped former glass shards, and fragmented crystals of quartz and subordinate feldspars. Scattered spherulites and lack of welding-compacted fiamme suggest that the lower member was slightly welded, where as the upper member contains sericite-replaced glass shards with preserved primary shapes indicating no welding. Undisturbed layers of ash-siltstone with normal grading and fluid–escape structures are attributed to subaqueous deposition below storm wave base in the eastern part of the inlier, where as erosion channels and cross-bedding in some of the volcaniclastic deposits imply deposition and reworking above wave base in the central part of the inlier. Epidote spots, previously interpreted as altered limestone fragments and an indicator for subaquatic deposition, are here reinterpreted as the result of selective alteration related to the intrusion of mafic dykes and to Ca release during dolomitisation of limestone.

  • 15.
    Ebbestad, Jan Ove R.
    et al.
    Uppsala University, Music and Museums, Museum of Evolution.
    Hogstrom, Anette E. S.
    Frisk, Åsa M.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Martma, Tonu
    Kaljo, Dimitri
    Kroger, Bjorn
    Parnaste, Helje
    Terminal Ordovician stratigraphy of the Siljan district, Sweden2015In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 137, no 1, p. 36-56Article, review/survey (Refereed)
    Abstract [en]

    Integration of new isotopic data and earlier biostratigraphic information from eight sections through the terminal Ordovician (Pirgu and Porkuni stages) of the Siljan district, Sweden, allows a more precise correlation of sections in terms of biostratigraphy and carbon isotope dating. Four levels with positive delta C-13 excursions are identified (from bottom) - the Moe, an unnamed excursion, Paroveja and Hirnantian Carbon Isotope Excursion (HICE). The delta C-13 values through the Boda Limestone are 1-2 parts per thousand higher than usual in Baltica, only the values for the HICE remains within what is expected. Background values increase from 1.5 parts per thousand in the bottom of the core of the Boda Limestone up to 3 parts per thousand in the top of it. The HICE is identified in five of eight sections and the main peak falls according to inferred correlation within the Metabolograptus persculptus Biozone, at or close to the Hindella beds in the Upper Boda Member. The late Katian (Pirgu) age of Holorhynchus in the Siljan district is clear and its co-occurrence with the chitinozoan Belonechitina gamachiana in Estonia supports a Katian age for this zone. The base of the Ozarkodina hassi Biozone may occur within units B-C of the Upper Boda Member and in the upper part of the Loka Formation and most likely is correlated with the M. persculptus Biozone. The Hirnantia-Dalmanitina faunas reported from the lowermost part of the Loka Formation and units B-D of the Upper Boda Member seem to range through all the Hirnantian, but detailed morphological studies allow to distinguish an older (=extraordinarius) and a younger (=persculptus) fauna.

  • 16.
    Ebbestad, Jan Ove R.
    et al.
    Uppsala University, Music and Museums, Museum of Evolution.
    Pour, Mansoureh Ghobadi
    Natl Museum Wales, Dept Geol, Cathays Pk, Cardiff CF10 3NP, S Glam, Wales.;Golestan Univ, Dept Geol, Fac Sci, Gorgan, Iran..
    Bassett, Michael G.
    Natl Museum Wales, Dept Geol, Cathays Pk, Cardiff CF10 3NP, S Glam, Wales..
    Popov, Leonid E.
    Natl Museum Wales, Dept Geol, Cathays Pk, Cardiff CF10 3NP, S Glam, Wales..
    First occurrence of Lesueurilla prima (Gastropoda) from the Middle Ordovician (Darriwilian) of Iran2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, no 4, p. 510-518Article in journal (Refereed)
    Abstract [en]

    The near planispiral euomphaloid gastropod Lesueurilla prima (Barrande in Perner) is a typical part of the cold water Mediterranean fauna in the Lower and Middle Ordovician. It is a signature species in strata of this age in the Prague Basin in the Czech Republic, Montagne Noire in France, and Central Morocco. The species is reported for the first time from the Darriwilian of Iran where it occurs in the upper part of the Shirgesht Formation of the Derenjal Mountains north of Tabas in east Central Iran. It occurs with a small species of the bellerophontoid gastropod Sinuites sp., as well as the calymenid trilobite Neseuretinus birmanicus (Reed) and the pliomerid trilobite Ovalocephalus kanlingensis (Zhang). The biogeographic distribution of Lesueurilla suggests that the genus had its origin in cold water, high-latitude peri-Gondwana areas during the Lower Ordovician, spreading to other peri-Gondwana areas and low-latitude areas of North China, Tarim, and finally Baltica, Laurentia and Australia in the late Middle and Upper Ordovician.

  • 17.
    Ebbestad, Jan Ove R.
    et al.
    Uppsala University, Music and Museums, Museum of Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Rushton, Adrian W. A.
    Stein, Martin
    Weidner, Thomas
    A paradoxidid moult ensemble from the Cambrian of Sweden2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 1, p. 18-29Article in journal (Refereed)
    Abstract [en]

    A mass aggregation of 148 paradoxidid trilobites and associated specimens of the agnostoid Pentagnostus praecurrens is preserved on a surface of a split orsten lens from the Middle Cambrian Series 3 Acadoparadoxides pinus-P. praecurrens Zone in Jamtland, Sweden. Most specimens are complete or nearly complete, lying parallel to the sediment surface and seem unaffected by currents or sorting. The association is interpreted as a moult ensemble. Paradoxidid specimens are represented by two taxa, identified as paradoxidid sp. 1 (n=28 specimens) and Eccaparadoxides sp. 2 (n=45 specimens). The species are preserved both dorsum up and dorsum down, in about equal number, which may reflect a natural tendency to moult in either posture. They probably moulted by opening the cephalic sutures along the wide rostrum. The dorsal sutures are invariably open and the librigenae are very often displaced, commonly backwards in relation to the cranidium, but not symmetrically in relation to the axial shield. The glabella of the paradoxidids is often crushed, so that sometimes the underlying hypostome is outlined. Very few examples show the joint between the cranidium and the trunk being broken. Facies interpretation suggests deposition below storm wave base. Rapid burial, possibly by blanketing from hypopycnal flows followed by an extended period of slow sediment input (Type 1 facies of Brett et al. 2012) may explain the unusual preservation. The animals may have lived in an ex-aerobic environment, but evidence to support this is at the moment insubstantial.

  • 18.
    Egenhoff, Sven
    et al.
    Colorado State Univ, Dept Geosci, Ft Collins, CO 80523 USA.
    Maletz, Jörg
    Free Univ Berlin, Inst Geowissensch, Berlin, Germany.
    Ahlberg, Per
    Lund Univ, Dept Geol, Lund, Sweden.
    Mast, Allison
    Colorado State Univ, Dept Geosci, Ft Collins, CO 80523 USA.
    Frisk, Åsa
    Uppsala University, Music and Museums, Museum of Evolution.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Newby, Warren
    Colorado State Univ, Dept Geosci, Ft Collins, CO 80523 USA;Total Oil & Gas, Houston, TX 77010 USA.
    Sedimentology of the Lower Ordovician (upper Tremadocian) Bjørkasholmen Formation at Flagabro, southern Sweden2018In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 140, no 1, p. 55-65Article in journal (Refereed)
    Abstract [en]

    The Lower Ordovician Bjørkasholmen Formation at Flagabro, Scania, southern Sweden, consists of a 0.8m thick succession of carbonates with three siliciclastic mudstones, 5, 1 and 100mm thick, intercalated in the central part of the unit. Carbonate and siliciclastic mudstone beds show both normal and inverse grading. The carbonates are mud-rich and subdivided into a mudstone, a wackestone and a packstone facies. Grain types in the carbonates are mostly shells and shell fragments of brachiopods and trilobites. The carbonate rocks are strongly bioturbated seen as in roundish burrows filled with mud and a clear cement; additionally, bioturbation is reflected in the random orientation of shells. The siliciclastic mudstones are subdivided into two facies; one contains large amounts of shells and is in part grain-supported, the other is matrix-dominated and laminated to massive. The succession reflects sedimentation on a low-inclined shelf equivalent to a mid-ramp to basinal setting. Most mud- and wackestones (facies 3 and 4) represent fair-weather sedimentation, and the intercalated wacke- and packstones (facies 4 and 5) represent concentration of shell debris during high-energy storm. The siliciclastic mudstones in the central part of the succession reflect deposition in a basinal setting. The entire BjOrkasholmen Formation at Flagabro is equivalent to a lowstand of third (?) order without a well-developed internal cyclicity and is in that respect similar to the Bjørkasholmen Formation of oland, but different from the age-equivalent Norwegian sections.

  • 19.
    Egerquist, Eva
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology, Palaeontology group.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Early-Middle Ordovician (Billingen-Volkhov stages) Orthide and Protorthide brachiopods from the East Baltic2006In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 128, no 4, p. 339-348Article in journal (Refereed)
    Abstract [en]

    Three new orthide species: Orthidium lavensis, Orthidium gambolovensis and Ranorthis rotunda, and one new protorthide species: Skenidioides minutus, are described from the Early-Middle Ordovician (Billingen-Volkhov stages) of Estonia and north-western Russia. This is the first record of Orthidium from Baltica, whereas Skenidioides was known previously only from the Keila and Oandu stages in Estonia.

  • 20.
    Einarsson, Elisabeth
    et al.
    Lund University.
    lindgren, Johan
    Lund University.
    Kear, Benjamin P.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Siverson, Mikael
    Western Australian Museum.
    Mosasaur bite marks on a plesiosaur propodial from the Campanian (Late Cretaceous) of southern Sweden2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, no 2, p. 123-128Article in journal (Refereed)
    Abstract [en]

    Although plesiosaurs and mosasaurs co-existed for about 35 million years at the end of the Cretaceous, the fossil record documenting interactions between these two groups of marine reptiles is meagre. The discovery of deeply incised scars on a limb bone of an immature polycotylid plesiosaur from the latest early Campanian (in the European two-fold division of the Campanian Stage) of the Kristianstad Basin, southern Sweden, is thus significant because it represents a rare example of predation or scavenging on an immature polycotylid plesiosaur by a large mosasaur.

  • 21.
    Ernst, Andrej
    et al.
    Hamburg University.
    Bogolepova, Olga
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Uppsala Centre for Russian and Eurasian Studies.
    Gubanov, Alexander P.
    Uppsala University, Music and Museums, Museum of Evolution.
    Two bryozoan assemblages from the Ordovician of the Russian Arctic2017In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 139, no 3, p. 205-215Article in journal (Refereed)
    Abstract [en]

    Two assemblages from the Ordovician rocks of the Arctic region contain exclusively trepostome bryozoans. The first assemblage from the Yunoyaga Formation (Middle Ordovician) of Maly Oleniy Island, Novaya Zemlya, contains Monticulipora mammulata d’Orbigny, 1850 and Nicholsonella vaupeliformis Modzalevskaya, 1955. Both species possess thick-branched ramose colonies characteristic for rather high energy environments. The second assemblage comes from two localities of the Stroinaya Formation (Upper Ordovician) of the October Revolution Island containing the single species Amplexopora angusta Astrova, 1965. The monospecific bryozoan fauna of branched, rarely encrusting growth forms and sedimentological characteristics of embedding rocks (floatstone) suggest low energy conditions in deeper environments, apparently accompanied by high salinity conditions.

  • 22.
    Frisk, Åsa M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Paragastropoda, Tergomya and Gastropoda (Mollusca) from the Upper Ordovician Dalby Limestone, Sweden2007In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, no 2, p. 83-99Article in journal (Refereed)
    Abstract [en]

    A fauna of 12 species of paragastropods, tergomyans and gastropods is described from the Upper Ordovician (Kukruse Stage to Idavare substage) Dalby Limestone of Tvären, Lockne, and Fjäcka (Sweden), presenting a higher diversity than previously recognized. The presence of Mimospira, Laeogyra, Sarkanella epelys n. sp. indicates a strong faunal connection with Bohemia, Czech Republic. Sarkanella is reported from outside Bohemia for the first time. Bucania erratica n. sp. represents one of the earliest records of the genus in Baltoscandia. A single case of shell repair from failed predation is recorded in this species. Synonyms for Eccyliopterus princeps Remelé and E. regularis Remelé are proposed. The significance of Laeogyra, Eccyliopterus, and Deaechospira for regional correlation within the Upper Ordovician of Baltoscandia is confirmed.

  • 23.
    Frisk, Åsa M
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Trilobite bio and ecostratigraphy of the Tremadocian Djupvik and Köpingsklint formations (A. serratus trilobite Zone) on southern Öland, Sweden2008In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 130, no 3, p. 153-160Article in journal (Refereed)
    Abstract [en]

    Trilobites of the late Tremadocian Apatokephalus serratus trilobite Zone, the Ceratopyge fauna, are abundant and widely distributed across Baltoscandia. During the Tremadocian they occur in the initial stable carbonate deposits on the platform (the Bjørkåsholmen Formation in the west; Djupvik and Köpingsklint formations in the east). Two sections at Ottenby and Degerhamn, southern Öland, Sweden, were investigated for trilobite abundance distribution. At Degerhamn and Ottenby the fauna is restricted to 70 and 78 cm respectively. In the Degerhamn quarry the fauna appears in the Djupvik Formation. At both localities the abundance distributions are similar, with an initial dominance of Ceratopyge acicularis and Shumardia pusilla, followed by a marked shift to a dominance of nileid species (Symphysurus angustatus, Varvia longicauda, Nileus limbatus). Comparisons with the Oslo Region showed a remarkably similar distribution pattern, and three biofacies are recognized. In the Oslo Region the Ceratopyge-Shumardia biofacies, the Bienvillia biofacies, and the nileid biofacies are developed. Only two of these are present on Öland, where the short lived drowning represented by the Bienvillia biofacies in the Oslo Region is not recorded. Within the nileid biofacies, Nileus and Varvia are more frequent on Öland than in the Oslo Region. The three biofacies may be applied to other areas of the Baltoscandian platform where this facies is present and potentially be used to discriminate depth gradients.

  • 24.
    Fu, Dongjing
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Zhang, Xingliang
    Budd, Graham E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The first dorsal-eyed bivalved arthropod and its significance for early arthropod evolution2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 1, p. 80-84Article in journal (Refereed)
    Abstract [en]

    A new bivalved arthropod Erjiecaris minusculo gen. et sp. nov. is described from the Lower Cambrian Chengjiang Lagerstatte, Yunnan, southwest China. It possesses mosaic features, such as the reduced shield that is dorsoventrally flattened, dorsally positioned eyes, ring-shaped somites and broad furcal rami. These provide an important link for assessing the evolutionary morphological gap between two distinctive Cambrian arthropod groups, crustaceanomorph and trilobite-like taxa. Thus, the new finding reported here in turn improves the understanding of the body plan of early arthropods and provides fresh insight into the evolution of the carapace/head shield and visual system.

  • 25.
    Gee, David G.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Andreasson, Per-Gunnar
    Lund Univ, Dept Geol, Lund, Sweden..
    Li, Yuan
    MLR Inst Geol, Beijing, Peoples R China..
    Krill, Allan
    Norwegian Univ Sci & Technol, Dept Geol & Mineral Resources, Trondheim, Norway..
    Baltoscandian margin, Sveconorwegian crust lost by subduction during Caledonian collisional orogeny2017In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 139, no 1, p. 36-51Article in journal (Refereed)
    Abstract [en]

    Underthrusting of Laurentia by the continental margin of Baltica during Caledonian orogeny resulted in the lateral emplacement of Iapetus Ocean-related terranes of the Upper Allochthon at least 500 km onto Baltica. The underlying Lower and Middle allochthons of the Baltoscandian margin mostly comprise Cryogenian, Ediacaran and Cambro-Silurian sedimentary successions; basement to these formations are present only as minor, isolated fragments, except at the base of the Middle Allochthon and within the underlying windows. The upper parts of the Middle Allochthon are notable for the presence of early Ediacaran dyke-swarms and other components of the Baltoscandian continent-ocean transition zone (COT). New data are presented here on the c. 610 Ma age of the COT-related dolerites in the Kalak Nappe Complex in Northern Norway and also on detrital zircons in the underlying Laksefjord and Gaissa nappes. The former confirms that the Baltoscandian COT has a similar age along the length of the orogen; the latter shows that the detrital zircon signatures in the Lower and Middle allochthons are comparable throughout the orogen. These sedimentary rocks have dominating populations of Mesoproterozoic to latest Palaeoproterozoic zircons similar to those from southern parts of the orogen, where Sveconorwegian complexes comprise the basement to the Caledonides. Thus, they help define the probable character and age of the crystalline basement that existed along this outer margin of Baltica during the Neoproterozoic, continental lower crust that was partly subducted during Ordovician continent-arc collision and subsequently lost beneath Laurentia during the 50 million years of Scandian collisional orogeny.

  • 26.
    Gee, David G.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Juhlin, Christopher
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Pascal, Christophe
    Geological Survey of Norway.
    Robinson, Peter
    Geological Survey of Norway.
    Collisional Orogeny in the Scandinavian Caledonides (COSC)2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, no 1, p. 29-44Article in journal (Refereed)
    Abstract [en]

    The COSC project is focused on the mid Paleozoic Caledonide Orogen in Scandinavia in order to better understand orogenic processes, both in the past and in today's active mountain belts. It relates to two of ICDP's main themes - the fundamental physics of plate tectonics and heat, mass and fluid transfer through Earth's crust, and on improving interpretation of geophysical data used to determine the structure and properties of the Earth's crust. Lateral transport of Caledonian allochthons over distances of several hundreds of kilometers in the Scandes, by a combination of thrusting and ductile extrusion, is comparable to that recognized in the Himalayas. The Caledonides in Scandinavia provide special opportunities for understanding Himalayan-type orogeny and the Himalayan Orogen itself, thanks to the deep level of erosion and the paucity of superimposed post-Paleozoic deformation. The surface geology in combination with the seismic, magnetotelluric, magnetic and gravity data provide control of the geometry of the Caledonian structure, both of the allochthon and the underlying parautochthon-autochthon, and define the locations for drilling. The latter will investigate both the high-grade, ductile Caledonian nappes and the underlying allochthons and basement, with two c. 2.5km deep boreholes, located near re and Jarpen in western Jamtland. The two boreholes will also provide unique information about other important aspects of the Scandinavian bedrock, including the heat flow and potential for geothermal energy, mineralization in the Seve nappes and alum shales, the uplift history of the Scandes, the Holocene paleoclimatological changes and the deep biosphere.

  • 27. Grad, M.
    et al.
    Tiira, T.
    Olsson, Sverker
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Komminaho, K.
    Seismic lithosphere-asthenosphere boundary beneath the Baltic Shield2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 4, p. 581-598Article in journal (Refereed)
    Abstract [en]

    The problem of the existence of the asthenosphere for old Precambrian cratons is still discussed. In order to study the seismic lithosphere-asthenosphere boundary (LAB) beneath the Baltic Shield, we used records of nine local earthquakes with magnitudes ranging from 2.7 to 5.9. To model the LAB, original data were corrected for topography and Moho depth using a reference model with a 46-km-thick crust. For two northern events at Spitsbergen and Novaya Zemlya, we observe a low-velocity layer, 60-70-km-thick asthenosphere, and the LAB beneath Barents Sea was found at depth of c. 200km. Sections for other events show continuous first arrivals of P-waves with no evidence for "shadow zone" in the whole range of registration, which could either be interpreted as the absence of the asthenosphere beneath the central part of the Baltic Shield, or that the LAB in this area occurs deeper (>200km). The relatively thin low-velocity layer found beneath southern Sweden, 15km below the Moho, could be interpreted as small-scale lithospheric heterogeneities, rather than asthenosphere. Differentiation of the lower lithosphere velocities beneath the Baltic Shield could be interpreted as regional heterogeneity or as anisotropy of the Baltic Shield lithosphere, with high velocities approximately in the east-west direction, and slow velocities approximately in the south-north direction.

  • 28.
    Gubanov, Alexander P.
    et al.
    Uppsala University, Music and Museums, Museum of Evolution.
    Bogolepova, Olga K.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Uppsala University.
    Early Ordovician molluscs with preserved colour pattern from the Timan-Pechora Basin of Russia2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 1, p. 85-89Article in journal (Refereed)
    Abstract [en]

    Unique preservation of the oldest colour pattern (approximate to 490Ma) of a molluscan shell and the first record of colour pattern in monoplacophorans are reported from a well that penetrated Early Ordovician strata in the Timan-Pechora Basin of Russia. The unusual preservation reflects low subsidence temperatures and minimal tectonic deformation. A colour pattern in the form of radial stripes coincides with the pattern of multiple muscle attachments to the shell, which obviously influenced the mantle margin responsible for the shell formation and pigment deposition. We assume that this type of colour pattern is one of the most ancient to have appeared in molluscan evolution.

  • 29.
    Gubanov, Alexander P.
    et al.
    Uppsala University, Music and Museums, Museum of Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Männik, Peep
    Tallinn University of Technology.
    The problematic mollusc Jinonicella from the Silurian of North America2017In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 139, no 3, p. 216-218Article in journal (Refereed)
    Abstract [en]

    The small problematic mollusc Jinonicella kolebabai Pokorný, 1978 is described from the lower Silurian Laketown Dolostone at Barn Hills in Utah, USA. The associated conodonts suggest a late Telychian age for the assemblage, which makes this the oldest occurrence of this species. Previous Silurian records of Jinonicellawere known from the Sheinwoodian to Ludfordian of Bohemia, the Czech Republic, Gotland, Sweden and the Carnic Alps of Austria.

  • 30.
    Herbert, Roger B.
    Stockholm Univ, Dept Geol & Geochem.
    Compositional zoning in Fe oxyhydroxides: An electron microprobe study1999In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 121, no Part 3, p. 221-226Article in journal (Refereed)
    Abstract [en]

    Compositional zoning in iron oxyhydroxides precipitated from mine drainage-contaminated groundwater was studied by electron microprobe (EMP) analysis. The observed zoning is characterized by variations in Al, Fe, S, and Si concentrations, with mean precipitate concentrations of ca. 56.0 wt.% Fe, 1.1 wt.% Al, 2.0 wt.% Si, and 0.5 wt.% S. The analyses indicate an inverse relationship between AI-Si concentrations and Fe-S concentrations in the Fe oxyhydroxides. The results and groundwater data from the field site suggest that the origin of compositional zoning in the Fe oxyhydroxides is controlled by both surface complexation reactions involving Al3+ and H4SiO4, which affect goethite formation kinetics, and the Al/Fe and Si/Fe molar ratios in solution.

  • 31.
    Herbert, Roger B
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Ekström, Liselotte
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Sulfur biogeochemistry and the attenuation of metals in a natural wetland receiving mine drainage: contaminated groundwater2004In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 126, no 1, p. 165-165Article in journal (Refereed)
  • 32.
    Holmer, Lars E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Popov, Leonid E.
    Natl Museum Wales, Dept Geol, Cardiff, S Glam, Wales.
    Klishevich, Inna
    St Petersburg State Univ, Geol Fac, Dept Hist Geol, St Petersburg, Russia.
    Ghobadi Pour, Mansoureh
    Golestan Univ, Dept Geol, Fac Sci, Gorgan, Iran.
    Reassessment of the early Triassic lingulid brachiopod ‘Lingula’ borealis Bittner, 1899 and related problems of lingulid taxonomy2016In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 138, no 4, p. 519-525Article in journal (Refereed)
    Abstract [en]

    The Early Triassic (late Induan to early Olenekian) Lingula borealis Bittner, from the Russkii Island on the Pacific cost of south-eastern Russia is revised, based on re-examination of the type material. Although this species, like most described Triassic lingulids, has remained very poorly understood due to the lack of information on important characters, such as musculature and mantle canals, it has been commonly recorded in subsequent studies and included in attempts at understanding the patterns of extinction and recovery at around the Permian-Triassic boundary. Linguliform brachiopods are some of the notable survivors of this significant mass extinction event. Lingula borealis has previously been referred to Lingularia and provisionally synonymised with Lingularia similis Biernat & Emig. Here, it is shown that it differs from Lingularia similis mainly in characters of mantle canals, musculature and most importantly in details of the pedicle nerve impression. In Lingularia borealis, the impression of the pedicle nerve is symmetrical and goes almost straight between the individual ventral umbonal muscle scars, whereas in Lingularia similis it is asymmetrically positioned towards the smaller left component of the ventral umbonal muscle scar. Shell structures and details of preserved ontogenies have also proven to be important for the discrimination of lingulid taxa, but cannot be provided from the types of Lingularia borealis.

  • 33.
    Holmer, Lars Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Redescription of the Ordovician acrotretoid brachiopod Conotreta Walcott, 18892000In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 122, no 3, p. 313-318Article in journal (Refereed)
    Abstract [en]

    The type species of the poorly understood Ordovician acrotretoid brachiopod Conotreta, C. rusti Walcott, 1889, is redescribed, based on a re-study of the syntypes and new topotypes from the Ordovician (late Mohawkian; late Caradoc) Denmark Limestone at Tr

  • 34.
    Holmer, L.E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Popov, L
    Lehnert, O
    Cambrian phosphatic brachiopods from the Precordillera of western Argentina1999In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 121, p. 227-242Article in journal (Refereed)
    Abstract [en]

    The first Cambrian phosphatic brachiopods (Subphylum Linguliformea, Class Lingulata) are described from the San Juan Precordillera of western Argentina, including Neotreta tumida Sobolev, Quadrisonia minor Rowell & Henderson, Prototreta cf. mimica Bell, C

  • 35. Högdahl, Karin
    1.86-1.85 Ga emplacement ages for K-feldspar megacryst bearing granites from the type area for the Revsund granites in Jämtland County, central Sweden2000In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 122, no 4, p. 359-366Article in journal (Refereed)
    Abstract [en]

    The type area of the coarse-grained, K-feldspar megacrystbearing Revsund granites is located in Jämtland County. These granites cover an area of c. 6.000 km2 in the western part of northern Sweden, and their emplacement ages have been established to c. 1.80 Ga from granites located outside and at the margin of the type area. Some of the rocks originally classified as Revsund granite in the southeastern part of Jämtland have later been interpreted to belong to the early Svecofennian suite. U-Pb SIMS analyses of zircon from one such rock and two Revsund granites from the type area, yield indistinguishable ages: 1854±8, 1858±9, and 1859±11 Ma, respectively. These ages are considerably older than the established age, suggesting that there either are two magmatic events forming the Revsund granites or that further K-feldspar megacryst-bearing granites in the type area must be re-classified. The ages achieved partly overlap with the ages of the 1.84–1.85 Ga, Kfeldspar megacryst-bearing Ljusdal granitoids located to the southeast. However, these rocks are metamorphosed and penetratively deformed, and have thus experienced a different tectonometamorphic evolution than have the Revsund granites in Jämtland, which are mainly isotropic outside shear zones.

  • 36. Högdahl, Karin
    et al.
    Jonsson, Erik
    Selbekk, Rune
    Geological relations and U-Pb geochronology of Hyttsjö granites in the Långban-Nordmark area, western Bergslagen, Sweden2007In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, p. 43-54Article in journal (Refereed)
    Abstract [en]

    The Hyttsjö granites occur in the extensively mineralised Långban-Nordmark area in the westernmost part of the Bergslagen ore province. They have been classified as late Svecokarelian granites due to their homogeneous and generally isotropic appearance in addition to a WR Rb/Sr age. Moreover, they have been considered as possible candidates for supplying essential metals to epigenetic mineralisation in this classic ore district. Two Hyttsjö granites yield U-Pb zircon data ages of 1791±2 and 1793±3 Ma, respectively, which overlap with emplacement ages of the adjacent 1.80-1.78 Ga Filipstad suite belonging to the Transscandinavian Igneous Belt (TIB). Mafic rocks occur quite abundantly associated with the Filipstad-type granite (sensu lato) and various types of mafic enclaves as well as hybrid rocks are present, suggesting a co-magmatic origin. Such mafic intrusives are also exposed in the vicinity of most known Hyttsjö-type plutons. Not least our observations that the former exhibit back-veining by granitic melts suggest intimate causal and temporal relationships between granite formation and mafic TIB rocks. The Hyttsjö granites were probably produced through partial melting related to the intrusion of hot, mafic magmas in and along the border between the TIB and the Svecofennian supracrustal and subvolcanic rocks. Thus, all available observations and data suggest that the Hyttsjö granites are intimately related to and most probable a product of TIB magmatism. Also, they do not lend any support for the hypothesis that the formation of the Hyttsjö granites represent a temporally separate intrusive episode. The Hyttsjö granites are therefore unlikely to be discernibly responsible for specific mineralisation in this area.

  • 37.
    Högdahl, Karin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Sjöström, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Deep drilling in a Palaeoproterozoic hot orogen – potential for  deciphering the  orogenic accretion and physical properties of a tectonically layered crust2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, no 1, p. 55-63Article in journal (Refereed)
    Abstract [en]

    The Svecofennian is a large hot orogen composed of different accreted crustal units. The boundaries between these units are often characterised by major, steeply dipping shear zones with post-accretionary signatures. However, some of these shear zones have recorded an earlier and long-lived activity related to the accretionary episode, so have moderately eastward dipping shear zones identified in the eastern part of the Ljusdal Domain in the central part of the orogen. These shear zones, repeated at multiple lithostratigraphical levels, are associated with west verging asymmetric F2-folds indicating thrusting with imbricate slices in thickness comparable to those in the Caledonides. In the Ljusdal Domain these structures have been recognised in rock of significantly different metamorphic grade indicating thick-skin thrusting on the crustal scale possibly accompanied by channel flow. Information from deep drilling through these stacked units would shed light on the tectonostratigraphy and consequently the accretionary to post-accretionary evolution of hot orogens. In addition, information about groundwater circulation, geothermal energy potential and reservoir quality of tectonically layered rocks for e.g. CO2 sequestration experiments in crystalline rocks would be gained.

  • 38. Högdahl, Karin
    et al.
    Sjöström, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Gromet, L.P.
    Character and timing of Svecokarelian, late-orogenic ductile deformation zones in Jämtland, west central sweden2001In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 123, no 4, p. 225-236Article in journal (Refereed)
    Abstract [en]

    An anastomosing pattern of NW-SE to NNW-SSE trending, ductile shear zones have affected the Precambrian bedrock in central Jämtland. Spatially these structures are related to two major shear zone systems, the Storsjön-Edsbyn Deformation Zone (SEDZ) and the Hassela Shear Zone (HSZ). Several of the local zones occur between Lake Näkten and Lake Locknesjön and coincide with linear magnetic anomalies. The dextral kinematics recorded are emphasised by clockwise rotation of early Svecofennian rocks, that partly are arranged in a large-scale C/S pattern. Three different, ductile shear zones yield U-Pb titanite ages of 1801±1, 1799±7, and 1794±3 Ma, interpreted to date the deformation. Pale titanite overgrowths, colourless titanite, and apatite yield younger U-Pb ages (c. 1.75 Ga) which argue for a tectonic reactivation of the zones, or a later thermal and/or hydrothermal event, as indicated by intrusions of cross-cutting pegmatites and felsic dykes. A hydrothermal activity during the Caledonian orogeny is recorded in one of the deformation zones. This is shown by an altered fabric containing titanites with pale outer parts which are severely discordant in a U-Pb concordia diagram with a Palaeozoic lower intercept. Sm-Nd analyses on re-precipitated zircon grains also deviate considerably from a Palaeoproterozoic trend given by other minerals in the assemblage.

  • 39.
    Högström, Anette E. S.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Sturkell, Erik
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Lindström, Maurits
    Ormo, Jens
    Concentric impact structures in the Palaeozoic of Sweden - the Lockne and Siljan craters2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, no 1, p. 65-70Article in journal (Refereed)
    Abstract [en]

    The Ordovician age Lockne and Devonian Siljan craters are two of the largest impact structures in northern Europe. Both formed in targets with a thick, low-strength upper layer. This target configuration is known to generate concentric crater structures with an outer, shallow crater in the low-strength layer, surrounding a central, deeper crater in the more resistant substrate. The concentric craters of Lockne and Siljan are excellent models for studies of similar concentric craters on Earth and elsewhere in the Solar system. Several structural issues remain, and drilling through the craters within the Swedish Deep Drilling Program intends to address the following: the extent of the craters with respect to the time of impact; the effects of cratering on the basement; and the role of basement structure for the crater formation. A problem for the Lockne crater is the relation to the Caledonian orogeny and the lateral extension of the ejecta blanket - the rim is interrupted by a radial depression that has been interpreted both as primary and secondary, tectonically induced. A second feature to study is the deeper and older (1.82-1.80 Ga) NNW-SSE shear zones that cut the basement. In the Siljan area the development of mega block associations comprising the infilling of the graben is disputed. The blocks may either be formed by sagging of peripheral parts of the fault blocks or alternatively by major radial movement involving kilometre long transport.

  • 40.
    Högström, Anette
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Suzuki, Jutaro
    Armoured annelids and molluscs from the Upper Ordovician Boda Limestone, central Sweden2009In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 131, no 3, p. 245-252Article in journal (Refereed)
    Abstract [en]

    Sclerites of machaeridians (Annelida) and polyplacophorans (Mollusca) from the UpperOrdovician (Katian–Hirnantian) Boda Limestone of the Siljan district, central Sweden are described forthe first time. Four taxa of machaeridians were found, but with one exception they are either known froma single isolated sclerite or only one type of sclerite. The largest taxon is represented by an inner modifiedsclerite of Plumulites sp. A from Osmundsberget Quarry. The complete scleritome is estimated to havereached a length of 12–15 cm. A more diverse material allows the description of Plumulites eueides sp.nov. from Kallholn Quarry. Within smaller cavities in Solberga Quarry minute sclerites of two taxa werefound; Lepidocoleus sp., and Turrilepas sp. The latter record represents the third known Ordovicianoccurrence and the youngest from that period. Association with minute blind trilobites andconcentrations of tiny articulated ostracodes suggest that these small cavities represented cryptichabitats. Two polyplacophoran sclerites are also described: one intermediate sclerite of Chelodes sp. Afrom Jutja¨rn Quarry, with only the outer surface exposed, and one intermediate sclerite of Spicuchelodes?sp. from Kallholn Quarry, with only the inner surface exposed. These represent rare examples ofOrdovician chitons recorded from outside Laurentian terranes.

  • 41. Isakar, M.
    et al.
    Peel, John Stuart
    Uppsala University, Museums etc., Museum of Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Lower Cambrian helcionelloid molluscs from Estonia2007In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, no 3, p. 255-262Article in journal (Refereed)
    Abstract [en]

    Pleurotomaria? kunda pik, 1926 was correctly referred to the genus Aldanella Vostokova, 1962 more than 30 years ago, although its affinities are still debated. It has been described by several authors as a gastropod on account of its helically coiled shell but it is here referred to the Class Helcionelloida, a group of Cambrian-Ordovician untorted molluscs which are usually bilaterally symmetrical. A sub-sutural, spiral muscle scar trace on the internal mould is described, as is a possible attachment area on the umbilical shoulder. Impressions of a prismatic shell structure are present in the apical region. In the lower Cambrian (proposed Cambrian Series 1) Kestla Member of the Lontova Formation, Aldanella kunda occurs together with Anabarella Vostokova, 1962, another helcionelloid that is also characteristic of Cambrian Series 1 in Siberia. Scenella(?) discinoides Schmidt, 1888 from the slightly younger Tiskre Formation (Cambrian Series 2) was originally assigned to a genus widely interpreted as a mollusc, but this species has been re-interpreted recently as a possible stem group brachiopod.

  • 42.
    Kear, Benjamin P.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Maxwell, Erin E.
    Wiman's forgotten plesiosaurs: the earliest recorded sauropterygian fossils from the High Arctic2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 1, p. 95-103Article in journal (Refereed)
    Abstract [en]

    The first detailed reports of sauropterygian remains from the Arctic island of Spitsbergen (Svalbard Archipelago) were published as short notes in 1914 and 1916 by the eminent Swedish palaeontologist Carl Wiman. Since then, his original specimens have languished in obscurity despite recent discoveries renewing interest in the Scandinavian polar territories as a highly significant source of Mesozoic marine amniote fossils. A reassessment of Wiman's Spitsbergen collection housed in the Museum of Evolution at Uppsala University, Sweden, has identified a pistosaurid vertebral centrum from probable Upper Triassic (Carnian) sediments in the Tschermakfjellet Formation, and various plesiosaurian elements including a previously undocumented partial skeleton most likely derived from the restricted Upper Jurassic (Tithonian) bone bed of the SlottsmOya Member, Agardhfjellet Formation. Although fragmentary, Wiman's sauropterygian fossils are historically important and comprise one of the oldest stratigraphical occurrences from the Mesozoic Boreal high-latitude region of Europe.

  • 43.
    Kear, Benjamin P.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Carl Wiman's legacy: 100 years of Swedish palaeontology2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 1, p. 1-2Article in journal (Other academic)
  • 44.
    Kolstrup, E
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Water-borne macroscopic plant particle transport through central and northern Europe during warming phases: a hypothetical spreading mechanism for climatic pioneers2007In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, no 4, p. 307-313Article in journal (Refereed)
    Abstract [en]

    This paper presents a new hypothesis on spreading and immigration of pioneer plants. It is speculated that during phases of sudden climate warming, seeds and other parts of plants were transported by rivers from central Europe into the North Sea and the Baltic areas and drifted on to surrounding shores. Some parts have remained in the records as macrofossils, while in other cases the plants are proposed to have continued their life cycle in the new areas. The principle is illustrated by,examples from different areas and times: Weichselian Lateglacial finds in NW Germany suggest that tree trunks were brought northward. For central and northern Sweden exceptionally strong glacio-isostatic rebound could have followed pronounced land surface depression after the ice-sheet meltings. This would have transformed coasts to land quickly, promoting the growth of seeds and plants in areas that are now far inland. If this hypothesis is valid it can explain the presence of anomalously early, warm vegetations in newly deglaciated areas. The rapidity of water-borne immigration following a climatic warming can also open up for a possibility of quick immigration to other former near-coast areas and river banks in Europe. Based on an example of a warmth requiring palaeovegetation at Vrogum in Denmark and the fact that trees survived in central Europe during the coldest part of the Weichselian it is suggested that short-lived, palaeobotanically hitherto unknown warm phases might be worth looking for in the terrestric records.

  • 45. Lehnert, Oliver
    et al.
    Meinhold, Guido
    Arslan, Arzu
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Calner, Mikael
    Ordovician stratigraphy of the Stumsnas 1 drill core from the southern part of the Siljan Ring, central Sweden2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 2, p. 204-212Article in journal (Refereed)
    Abstract [en]

    The Stumsnas 1 core, drilled in 2011 in the southern part of the Siljan Ring, provides new insights into the stratigraphy of the Ordovician succession in central Sweden. The core section shows evidence of the structural complications caused by the late Devonian meteorite impact in the area. In the core, about 90m of Tremadocian to Darriwilian strata are sandwiched between Proterozoic igneous basement rocks. At the lower contact, the sedimentary succession starts with glauconitic, fine-grained siliciclastics and carbonates directly resting on the weathered basement. The basal siliciclastic unit is overlain by a ca. 19-m-thick limestone succession, well-known from this part of the Baltoscandian Basin, includes strata corresponding to the Latorp Limestone through the upper Holen Formation. This succession is covered by a limestone-marl alternating sequence, representing some yet unknown deeper water facies, presumably coeval to the topmost Holen Formation through upper Dalby Limestone. The upper third of the sedimentary succession in the core includes numerous slices of partly overturned strata, including relatively thick successions of the Slandrom Formation, Fjacka Shale and Jonstorp Formation, as well as carbonate and siliciclastic units of yet unknown stratigraphic origin.

  • 46. Lehnert, Oliver
    et al.
    Meinhold, Guido
    Bergstroem, Stig M.
    Calner, Mikael
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Egenhoff, Sven
    Frisk, Asa M.
    Hannah, Judith L.
    Hogstrom, Anette E. S.
    Huff, Warren D.
    Juhlin, Christopher
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Maletz, Joerg
    Stein, Holly J.
    Sturkell, Erik
    Vandenbroucke, Thijs R. A.
    New Ordovician-Silurian drill cores from the Siljan impact structure in central Sweden: an integral part of the Swedish Deep Drilling Program2012In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 134, no 2, p. 87-98Article in journal (Refereed)
    Abstract [en]

    New drill cores from the largest known impact structure in Europe, the relict of the Siljan meteorite crater, provide new possibilities to reconstruct Early Palaeozoic marine environments and ecosystems, and to document changes in sedimentary facies, sea level and palaeoclimate in Baltoscandia. The impact crater is an important target of the project "Concentric Impact Structures in the Palaeozoic" within the framework of the "Swedish Deep Drilling Program". Two core sections, Mora 001 and Solberga 1, have been analysed. The sedimentary successions of these core sections include strata of late Tremadocian through late Wenlock ages. Our preliminary studies show not only that several of the classical Palaeozoic units of Sweden are represented in the area, but also that other significantly different facies are preserved in the Siljan district. An erosional unconformity representing a substantial hiatus occurs between Middle Ordovician limestone and a Llandovery-Wenlock (Silurian) shale succession in the western part of the Siljan structure and suggests an extended period of uplift and erosion. This may be related to forebulge migration due to flexural loading by the Caledonian thrust sheet to the west. Thus, this part of Sweden, previously regarded as a stable cratonic area, presumably was affected by the Caledonian collision between Baltica and Laurentia.

  • 47.
    Li, Guoxiang
    et al.
    Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, People’s Republic of China.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Early Cambrian lingulate brachiopods from the Shaanxi Province, China2004In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 126, no 2, p. 193-211Article in journal (Refereed)
    Abstract [en]

    A diverse fauna of lingulate (Subphylum Linguliformea, Class Lingulata) brachiopods is described from the Early Cambrian (Qiongzhusian Stage) carbonates in southern Shaanxi Province (Fucheng and Xiaoyang sections), China. Eight species assigned to 6 genera are systematically described. Among them, the taxa assigned to the Superfamily Linguloidea comprise Palaeobolus liantuoensis Zeng, Lingulellotreta malongensis (Rong), Eoobolus aff. viridis (Cobbold), Eoobolus? shaanxiensis sp. nov., and Kyrshabaktella? sp. Only Palaeobolus liantuoensis and Lingulellotreta malongensis were known previously from South China, where the latter species occurs in the soft-bodied Chengjiang fauna with preserved pedicle. The Superfamily Acrotheloidea is represented only by the new species Botsfordia minuta. The fauna also includes two primitive acrotretoid (Superfamily Acrotretoidea) species belonging to the new genus and species Eohadrotreta zhenbaensis and E. zhujiahensis; the ontogeny of Eohadrotreta supports the view that the acrotretid muscle system and ontogeny are derived in relation to the lingulide musculature and ontogeny. The fauna from Shaanxi is the oldest known diverse lingulate brachiopod assemblage from China.

  • 48.
    Lorenz, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    The Swedish Deep Drilling Program: For Science and Society2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, no 1, p. 25-27Article in journal (Refereed)
  • 49.
    Lundgren, Mette
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Blom, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Phylogenetic relationships of the cyathaspidids (Heterostraci)2013In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 1, p. 74-84Article in journal (Refereed)
    Abstract [en]

    The present analysis investigates for the first time the phylogenetic relationships of the cyathaspidid heterostracans by the principle of global parsimony on the basis of 36 species and 1 outgroup taxon. In this study, which assumes cyathaspidid monophyly, states for 61 characters were compiled and analysed using maximum parsimony methods, resulting in nine shortest trees of 122 steps each. The strict consensus tree shows a high degree of homoplasy and challenges previous classification schemes. The consensus topology supports previous arguments that the tolypelepids with their characteristic scale-like ornament occupy a basal position among the cyathaspidids.

  • 50. Lundmark, Christina
    et al.
    Weihed, Pär
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences. Luleå tekniska universitet.
    Billström, Kjell
    Swedish Museum of Natural History.
    The Jokkmokk granitoid: an example of 1.88 Ga juvenile magmatism at the Archaean-Proterozoic border in northern Sweden2005In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 127, no 2, p. 83-98Article in journal (Refereed)
    Abstract [en]

    The Jokkmokk granitoid is exposed in a large plutonic massif northwest of Jokkmokk in northern Sweden. It is light grey to white, fine-grained, with megacrysts of feldspar and glomeroporphyritic hornblende and biotite. Small enclaves of mafic rocks and synplutonic mafic dykes are products of mingling with a coeval and possibly cogenetic mafic magma. The Jokkmokk granitoid was previously considered to belong to the c. 1.8 Ga Lina S-type intrusive suite, but the Jokkmokk granitoid has a unique calc-alkaline to alkali-calcic, metaluminous to weakly peraluminous, character with a moderate LREE enrichment and a flat HREE pattern, and a flat to slightly positive Eu-anomaly. U–Pb TIMS zircon dating of the Jokkmokk granitoid gives an age of 1883±15 Ma which is coeval with the emplacement of the Haparanda suite, but contrary to the Haparanda suite it displays a positive _Nd(t) value of 2.8, indicating a more juvenile Palaeoproterozoic character similar to the Jörn suite in the Skellefte district. This type of magma seems to be restricted to the palaeoboundary between the Archaean craton in the north and Palaeoproterozoic juvenile crust in the south. Spatial correlation with low angle, south dipping, WNW-trending shear zones and NNE-trending subvertical shear zones, highlight the possibility that this unique magma type is related to transtension in the overriding plate and partial melting in a sub-arc mantle wedge during NE-directed subduction processes related to the early stages of the Svecokarelian orogen. This type of setting has been advocated as the potentially most favourable tectonic setting for porphyry copper formation

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