DOCSLIB.ORG

Cartografia Geológica, Estratigrafia E Paleontologia Da Região De Rates E São Félix De

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Cartografia Geológica, Estratigrafia E Paleontologia Da Região De Rates E São Félix De Cartografia Geológica, Estratigrafia e Paleontologia da Região de Rates e São Félix de Laúndos Paula Cristina Faria Amorim Mestrado em Geologia Departamento de Geociências, Ambiente e Ordenamento do Território 2020 Orientador Doutora Maria Helena Macedo Couto, Professora Associada, Faculdade de Ciências da Universidade do Porto Todas as correções determinadas pelo júri, e só essas, foram efetuadas. O Presidente do Júri, Porto, ______/______/_________ FCUP v Cartografia Geológica, Estratigrafia e Paleontologia da Região de Rates e São Félix de Laúndos Agradecimentos Agradeço à Dra Helena Couto, pela orientação, pelos ensinamentos, pelo apoio e por toda a disponibilidade ao longo deste percurso, foi sempre incansável. Ao Sr Vítor Azevedo por me mostrar o património arqueológico da vila de São Pedro de Rates, nomeadamente a mina de ferro que tão importante foi para a região e para este trabalho. A colaboração no acesso às escavações da obra pertencente à Resulima do geólogo João Sebastião e da engenheira Nélia Figueiredo. À Dona Irene Lopes, do laboratório de preparação de amostra do Departamento de Geociências, Ambiente e Ordenamento do Território, pela realização das lâminas delgadas para o estudo petrográfico. À Dra Daniela Silva, do Centro de Materiais da Universidade do Porto, pela realização da análise no Microscopio Eletrónio de Varrimento (MEV), dando o seu parecer com base na sua experiência atendendo ao contexto da amostra. Ao Dr Yves Moёlo e ao Dr Frederico Sodré Borges pela ajuda na identificação e compreensão na análise ao MEV de certos minerais. Um agradecimento especial aos amigos que levo para a vida, os meus colegas de curso, com os quais estes anos foram passados sempre a apoiar uns aos outros para chegarmos à meta final juntos. Agradeço especialmente pelo apoio incondicional dos meus pais e da minha irmã, por estarem sempre a apoiar e a ajudar em tudo o que podiam, e ainda um agradecimento especial ao Joel Rego, pois sem eles não seria possível chegar até aqui. FCUP vi Cartografia Geológica, Estratigrafia e Paleontologia da Região de Rates e São Félix de Laúndos Resumo O presente trabalho teve como principal objetivo a elaboração de uma carta geológica de pormenor da região de Rates e São Félix de Laúndos. Durante o trabalho de campo foi feita identificação das diferentes unidades litoestratigráficas e efetuada a colheita de amostras de rocha e de fósseis. Algumas das amostras de rocha foram posteriormente estudadas, em lâmina delgada, ao microscópio ótico e ao Microscópio Eletrónico de Varrimento (MEV). O estudo paleontológico foi efetuado nas amostras colhidas no campo, essencialmente pertencentes ao Ordovícico Médio (Formação de Valongo), também ao Silúrico e ao Carbonífero. Nas formações do Devónico, cobertas em grande parte por campos agrícolas, não foi possível encontrar qualquer exemplar. Foram sim, estudados alguns fósseis do Devónico da região de Rates e Laúndos pertencentes à Coleção Estratigráfica e Paleontológica do Departamento de Geociências, Ambiente e Ordenamento do Território da Faculdade de Ciências da Universidade do Porto. Estes fósseis pertencentes a antigas coleções foram objeto de vários estudos, e através dos trabalhos publicados foi possível fazer uma inventariação e obter a localização aproximada da colheita dos vários exemplares no Google Earth. Os trabalhos cartográficos desenvolvidos na região remontam ao séc. XX. No presente trabalho fez-se uma cartografia de mais pormenor, complementada com estudos laboratoriais. Localmente foi feita a reinterpretação da sequência estratigráfica. Foi assinalada a presença de rochas vulcânicas, nomeadamente um riolito e um tufo vulcanogénico nas alternâncias vulcano-sedimentares do Câmbrico – Ordovícico Inferior, subjacentes aos quartzitos do Floiano, uma rocha vulcanogénica que sobrepõe os quartzitos do Hirnantiano, provavelmente do Ordovícico Superior e pórfiros intercalados no conglomerado-brecha do Carbonífero, não identificados anteriormente nesta região. Em alguns locais foram realizados perfis geológicos interpretativos. Palavras chave: Cartografia, Estratigrafia, Paleontologia, Petrologia, Rates, São Félix de Laúndos FCUP vii Cartografia Geológica, Estratigrafia e Paleontologia da Região de Rates e São Félix de Laúndos Abstract The present work had as main objective the elaboration of a detailed geological map of the Rates and São Félix de Laúndos region. During the fieldwork different lithostratigraphic units were identified and samples of rock and fossils were collected. Some of the rock samples were subsequently studied, in thin section under the optical microscope and the Scanning Electron Microscope (SEM). The paleontological study was carried out on samples collected in the field, essentially belonging to the Middle Ordovician (Valongo Formation), also to Silurian and Carboniferous. In the Devonian formations, largely covered by agricultural fields, it was not possible to find any specimen. Some Devonian fossils from the Rates and Laúndos region belonging to the Stratigraphic and Paleontological Collection of the Department of Geosciences, Environment and Spatial Planning of the Faculty of Sciences of the University of Porto were studied. These fossils belonging to old collections were the subject of several studies, and through the published papers it was possible to make an inventory and obtain the approximated location of the collection of the various specimens in Google Earth. The geological maps developed in the region date back to the XX century. In this work, a more detailed geological mapping was made, complemented with laboratory studies. Locally, the stratigraphic succession was reinterpreted. The presence of volcanic rocks, namely a rhyolite and a volcanogenic tuff, was noted in the volcano-sedimentary interbedded layers of the Cambrian – Lower Ordovician, underlying the Floian quartzites, an ignimbrite that overlaps the Hirnantian quartzites, probably of the Upper Ordovician and a porphyry interbedded in the Carboniferous conglomerate-breccia, not previously identified in this region. In some places, interpretive geological cross-section were made. Keywords: Cartography, Stratigraphy, Paleontology, Petrology, Rates, São Félix of Laúndos FCUP viii Cartografia Geológica, Estratigrafia e Paleontologia da Região de Rates e São Félix de Laúndos Índice Agradecimentos ............................................................................................................................... v Resumo ..............................................................................................................................................vi Abstract ............................................................................................................................................. vii Índice ................................................................................................................................................ viii Lista de Tabelas ................................................................................................................................xi Lista de Figuras ............................................................................................................................... xii Capítulo I – Introdução..................................................................................................................... 1 1. Introdução .......................................................................................................... 3 2. Objetivos ............................................................................................................ 3 3. Métodos e técnicas de trabalho .......................................................................... 3 3.1. Trabalho de campo ..................................................................................... 3 3.2. Estudo petrográfico ..................................................................................... 4 3.3. Estudo em Microscopia Eletrónica de Varrimento (MEV) ............................ 4 3.4. Estudo paleontológico ................................................................................. 4 Capítulo II – Enquadramento Geral ............................................................................................... 5 1. Enquadramento geográfico ................................................................................ 7 2. Enquadramento geomorfológico ........................................................................ 7 3. Enquadramento geológico-estrutural .................................................................. 8 3.1. Precâmbrico e/ou Câmbrico (Complexo Xisto-Grauváquico) ..................... 10 3.2. Ordovícico ................................................................................................. 10 3.3. Silúrico ...................................................................................................... 12 3.4. Devónico ................................................................................................... 13 3.5. Carbonífero ............................................................................................... 14 3.6. Depósitos do Plio-Pleistocénico ................................................................ 14 3.7. Rochas Magmáticas .................................................................................. 15 3.8. Recursos Minerais .................................................................................... 15 Capítulo III – Trabalho de Campo................................................................................................
Load more

Recommended publications
  • Shell Repair in Anticalyptraea (Tentaculita) in the Late Silurian (Pridoli) of Baltica
    Carnets de Géologie [Notebooks on Geology] - Letter 2012/01 (CG2012_L01) Shell repair in Anticalyptraea (Tentaculita) in the late Silurian (Pridoli) of Baltica 1 Olev VINN Abstract: Shell repair is common in the late Silurian (Pridoli) encrusting tentaculitoid tubeworm Anti- calyptraea calyptrata from Saaremaa, Estonia (Baltica), and is interpreted here as a result of failed predation. A. calyptrata has a shell repair frequency of 29 % (individuals with scars) with 17 speci- mens. There is probably an antipredatory adaptation, i.e. extremely thick vesicular walls, in the mor- phology of Silurian Anticalyptraea. The morphological and ecological evolution of Anticalyptraea could thus have been partially driven by predation. Key Words: Predation; shell repair; Tentaculita; Anticalyptraea; Pridoli; Silurian; Estonia. Citation: VINN O. (2012).- Shell repair in Anticalyptraea (Tentaculita) in the late Silurian (Pridoli) of Baltica.- Carnets de Géologie [Notebooks on Geology], Brest, Letter 2012/01 (CG2012_L01), p. 31- 37. Résumé : Réparation de la coquille chez Anticalyptraea (Tentaculita) dans le Silurien supé- rieur (Pridoli) du bouclier balte (Baltica).- La réparation de coquilles est habituelle chez Anticalyp- traea calyptrata, un vers tentaculitoïde encroûtant du Silurien supérieur (Pridoli) à Saaremaa, Estonie (bouclier balte), et est interprétée ici comme la conséquence d'une prédation qui aurait échoué. A. calyptrata a une fréquence de réparation de la coquille de 29% (individus présentant des cicatrices) pour 17 spécimens. Ceci est probablement une adaptation contre la prédation, c'est-à-dire la présence de parois vésiculaires et très épaisses, présentes dans la morphologie de l'Anticalyptraea du Silurien. L'évolution morphologique et écologique d'Anticalyptraea pourrait donc pour partie avoir été provoquée par la prédation.
    [Show full text]
  • A New Species of Conchicolites (Cornulitida, Tentaculita) from the Wenlock of Gotland, Sweden
    Estonian Journal of Earth Sciences, 2014, 63, 3, 181–185 doi: 10.3176/earth.2014.16 SHORT COMMUNICATION A new species of Conchicolites (Cornulitida, Tentaculita) from the Wenlock of Gotland, Sweden Olev Vinna, Emilia Jarochowskab and Axel Munneckeb a Department of Geology, University of Tartu, Ravila 14A, 50411 Tartu, Estonia; [email protected] b GeoZentrum Nordbayern, Fachgruppe Paläoumwelt, Universität Erlangen-Nürnberg, Loewenichstr. 28, 91054 Erlangen, Germany Received 2 June 2014, accepted 4 August 2014 Abstract. A new cornulitid species, Conchicolites crispisulcans sp. nov., is described from the Wenlock of Gotland, Sweden. The undulating edge of C. crispisulcans sp. nov. peristomes is unique among the species of Conchicolites. This undulating peristome edge may reflect the position of setae at the tube aperture. The presence of the undulating peristome edge supports the hypothesis that cornulitids had setae and were probably related to brachiopods. Key words: tubeworms, tentaculitoids, cornulitids, Silurian, Baltica. INTRODUCTION Four genera of cornulitids have been assigned to Cornulitidae: Cornulites Schlotheim, 1820, Conchicolites Cornulitids belong to encrusting tentaculitoid tubeworms Nicholson, 1872a, Cornulitella (Nicholson 1872b) and and are presumably ancestors of free-living tentaculitids Kolihaia Prantl, 1944 (Fisher 1962). The taxonomy (Vinn & Mutvei 2009). They have a stratigraphic range of Wenlock cornulitids of Gotland (Sweden) is poorly from the Middle Ordovician to the Late Carboniferous studied, mostly due to their minor stratigraphical (Vinn 2010). Cornulitid tubeworms are found only in importance. normal marine sediments (Vinn 2010), and in this respect The aim of the paper is to: (1) systematically they differ from their descendants, microconchids, which describe a new species of cornulitids from the Wenlock lived in waters of various salinities (e.g., Zatoń et al.
    [Show full text]
  • Devonian Tentaculitoidea of the Malvinokaffric Realm of Brazil, Paraná Basin
    Palaeontologia Electronica palaeo-electronica.org Devonian Tentaculitoidea of the Malvinokaffric Realm of Brazil, Paraná Basin Jeanninny Carla Comniskey and Renato Pirani Ghilardi ABSTRACT The Tentaculitoidea is represented by extinct invertebrates characterized by small, conic, carbonate shells of animals that inhabiting exclusively marine environ- ments. The tentaculitoids occur from the Ordovician to Devonian, with diversity peak- ing in the Middle Devonian. The Tentaculitoidea has three orders: Tentaculitida (benthic habit), Homoctenida, and Dacryoconarida (planktonic habit). In Brazil, the old- est tentaculitoids occur in strata of the early Silurian, with the genus Tentaculites. Spec- imens of the Dacryoconarida and Homoctenida orders were only found in the Lower Devonian strata. In this study, we conducted taxonomic analyses of specimens in col- lections from various research institutions, including samples used in the last system- atic study with this group, in mid-1991. The present study aims to review the systematic aspects of the tentaculitoids of the Devonian strata, Paraná basin, Brazil. Seven species of tentaculitoids were identified: two species previously described, Ten- taculites jaculus and Tentaculites crotalinus and five news species: Tentaculites kozlo- wskii, Tentaculites paranaensis, Uniconus ciguelii, Homoctenus katzerii, and Styliolina langenii. This is the first known occurrence of the genus Uniconus in Devonian strata from Brazil. The analyzed species of homoctenids and dacryoconarids are larger than those previously described in the specialized literature. This study demonstrated that the tentaculitoids of the Paraná Basin have a stratigraphic distribution from the end of the Pragian to the early Givetian. Jeanninny Carla Comniskey. Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Pós-Graduação em Biologia Comparada, Universidade de São Paulo-USP.
    [Show full text]
  • A New Microconchid Species from the Silurian of Baltica
    Title: A new microconchid species from the Silurian of Baltic Author: Michał Zatoń, Olev Vinn, Ursula Toom Citation style: Zatoń Michał, Vinn Olev, Toom Ursula. (2016). A new microconchid species from the Silurian of Baltica. "Estonian Journal of Earth Sciences" (Vol. 65, iss. 2 (2016), s. 115-123), doi 10.3176/earth.2016.09 Estonian Journal of Earth Sciences, 2016, 65, 2, 115–123 doi: 10.3176/earth.2016.09 A new microconchid species from the Silurian of Baltica Michał Zatońa, Olev Vinnb and Ursula Toomc a Faculty of Earth Sciences, University of Silesia, Będzińska 60, 41-200 Sosnowiec, Poland; [email protected] b Department of Geology, University of Tartu, Ravila 14A, 50411 Tartu, Estonia; [email protected] c Institute of Geology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia; [email protected] Received 5 April 2016, accepted 29 April 2016 Abstract. The diversity of Silurian microconchids is still poorly understood. Here, a new microconchid tubeworm species, Palaeoconchus wilsoni, is described from the Silurian (Ludlow) encrusting rugose corals from Estonia (Saaremaa Island) and a brachiopod shell from Sweden (Gotland). In Estonia, the microconchids are a dominant constituent of the encrusting assemblages, associated with cornulitids, Anticalyptraea, auloporids, trepostome bryozoans, hederelloids and enigmatic ascodictyids. It is notable that these Silurian encrusting assemblages are clearly dominated by tentaculitoids (microconchids, cornulitids and Anticalyptraea) which very often co-exist on the same coral host. Morphologically similar microconchids and Anticalyptraea may have exploited a more similar ecological niche than the straight-shelled cornulitids. However, the clear predominance of microconchids over Anticalyptraea in the communities may indicate that this genus was a less effective competitor for food than microconchid tubeworms.
    [Show full text]
  • Silurian Cornulitids of Estonia (Baltica)
    Carnets de Géologie [Notebooks on Geology] - Article 2013/09 (CG2013_A09) Silurian cornulitids of Estonia (Baltica) 1 Olev VINN 2 Mark A. WILSON Abstract: Seven species of cornulitids are systematically described from the Silurian of Saaremaa and Hiiumaa islands, Estonia. There are three species of cornulitids in the Rhuddanian, three in the Shein- woodian, single species in the Gorstian and Ludfordian, and three species in the Pridoli. Cornulitids have a facies range from pelletal limestones of shoal environments to deeper ramp marls. Endobiotic cornulitid symbionts occur in stromatoporoids found in shoal and open shelf zones. Gregarious aggre- gates are restricted to the limestones of the open shelf zone possibly because of higher nutrient levels in open shelf zone waters as compared to those of the deeper ramp. Unattached free forms are espe- cially common in offshore deeper ramp marls presumably due to their adaption to life on a soft bottom. Solitary attached forms occur in all facies zones where cornulitids are present. Because the life modes of cornulitids are closely associated with particular facies zones, they are useful tools for paleoecologi- cal reconstructions. Key Words: Tentaculita; Cornulitida; sedimentary facies; stratigraphic distribution; Silurian; Baltica. Citation : VINN O. & WILSON M.A. (2013).- Silurian cornulitids of Estonia (Baltica).- Carnets de Géologie [Notebooks on Geology], Brest, Carnets de Géologie [Notebooks on Geology], Brest, Article 2013/09 (CG2013_A09), p. 357-368. Résumé : Cornulitides siluriens d'Estonie (Baltica).- Sept espèces de cornulitides provenant du Silurien des îles Saaremaa et Hiiumaa en Estonie sont décrites : trois espèces sont présentes dans le Rhuddanien, trois dans le Sheinwoodien, une dans le Gorstien et le Ludfordien, et trois espèces dans le Pridoli.
    [Show full text]
  • Microconchid Encrusters Colonizing Land Plants: the Earliest North American Record from the Early Devonian of Wyoming, USA
    Microconchid encrusters colonizing land plants: the earliest North American record from the Early Devonian of Wyoming, USA JOSEPH A. CARUSO AND ALEXANDRU M. F. TOMESCU Caruso, JA. & Tomescu, AM.F. 2012: Microconchid encrusters colonizing land plants: the earliest North American record from the Early Devonian of Wyoming, USA. Lethaia. DOI: 10.1111 ⁄ j.1502-3931.2012.00305.x Plant fossils in the Early Devonian Beartooth Butte Formation (Wyoming, USA) are col- onized by microconchid encrusters which are found on several plant taxa, at two fossil localities in the formation, and whose tube coil diameters range from 230 to 1170 lm. Colonization is densest on broad Drepanophycus devonicus stems where microconchid individuals encompassing broad size ranges co-occur in close vicinity. This indicates exposure to microconchid colonization and, therefore, submergence of the plant material for relatively extended periods of time prior to burial. For in situ preserved Drepanophy- cus, this suggests that the plants grew partially submerged and their submerged parts were colonized by microconchids while still alive. In turn, this indicates that by the Early Devonian microconchids were colonizing freshwater environments. The Beartooth Butte Formation provides the first record of plant colonization by microconchids in North America and, along with only one other Early Devonian record from Germany, the old- est evidence for microconchids colonizing plant substrates. h Devonian, encrusters, mi- croconchid, vascular plants, Wyoming. Joseph A. Caruso [[email protected]] and Alexandru M. F. Tomescu [mihai@hum- boldt.edu], Department of Biological Sciences, Humboldt State University, Arcata, CA 95521, USA; manuscript received on 25 ⁄ 9 ⁄ 2011; manuscript accepted on 20 ⁄ 12 ⁄ 2011.
    [Show full text]
  • Shell Injury and Anomalies in Devonian Dacryoconarid Tentaculites
    Unsuccessful predation on Middle Paleozoic plankton: Shell injury and anomalies in Devonian dacryoconarid tentaculites STANISLAVA BERKYOVÁ, JIŘÍ FRÝDA, and PAVEL LUKEŠ Berkyová, S., Frýda, J., and Lukeš, P. 2007. Unsuccessful predation on Middle Paleozoic plankton: Shell injury and anomalies in Devonian dacryoconarid tentaculites. Acta Palaeontologica Polonica 52 (2): 407–412. Anomalous development of shell ornamentation and repaired shell injury in the Early Devonian dacryoconarid tenta− culites are documented and interpreted as either a repaired injury of the shell (evidence of unsuccessful predation ob− scured by recrystallization), or as a result of an anomalous function of the mantle, caused by injury of the soft body. The manner of shell repair, which resembles the way that some modern marine animals, such as mollusks, repair their shells, is discussed. The issue of phylogenetic affinities of tentaculites has been also outlined. These findings represent the first documentation of unsuccessful predation on the Middle Paleozoic plankton. Key words: Tentaculitoidea, predation, shell repair, Devonian. Stanislava Berkyová [[email protected]], Charles University, Faculty of Science, Department of Geology and Pale− ontology, Albertov 6, 128 43 Prague and Czech Geological Survey, Geologicka 6, 150 00 Prague, Czech Republic; Jiří Frýda [[email protected]], Czech Geological Survey, Geologicka 6, 150 00 Prague, Czech Republic; Pavel Lukeš [[email protected]], Třebešovská 66/561, 193 00 Prague, Czech Republic. Introduction cessful predation is an extremely common phenomenon, which is directly manifested by repaired injuries. Shell repair In the last two decades much attention has been paid to pred− has generally been increasing throughout Paleozoic time ator−prey interactions and to the evolutionary significance of (Vermeij 2002).
    [Show full text]
  • Systematics 071718
    Invertebrate Paleontology Systematics Classification of Invertebrate Taxa for the Laboratory Fall 2018 The following is an annotated list of the taxa you will be identifying in the Invertebrate Paleontology lab. It is correlated with the groups we are covering in lecture, so you will also find this useful during class. Some taxa are not included because they are rare as specimens or relatively unimportant for paleontological fieldwork. When asked to “identify” a specimen on a lab test or in the field, please give the most specific taxonomic rank and name (e.g., “Class Hexactinellida”). This listing is revised every year – it is not the same as last year’s compilation. I’ve inserted spaces below the specific taxa so you can add notes and drawings. I’ve also left the backs of the pages blank so that you can use them for notes as well. Please let me know how you would improve this listing so that it is more helpful. You may use this entire book, the text as well as any notes and diagrams you add in your own handwriting, on the lab tests and the final lab- lecture examination. Table of Contents Phylum Haptophyta 2 Phylum Bacillariophyta 2 Phylum Foraminiferida 3 Phylum Radiolaria 4 Phylum Porifera 5 Phylum Cnidaria 7 Phylum Brachiopoda 11 Phylum Bryozoa 17 Phylum Hyolitha 19 Phylum Mollusca 20 Phylum Arthropoda 27 Phylum Echinodermata 32 Phylum Hemichordata 36 Phylum Annelida 37 Incertae sedis 37 Trace Fossils 39 Full Taxonomic List (Name and Age Ranges Only) 42 1 Nomina si nescis, perit et cognitio rerum If you do not know the names, the knowledge of these things vanishes (Linnaeus) Kingdom PROTISTA: Prepaleozoic – Recent A polyphyletic group used for convenience until the higher taxonomy is sorted out.
    [Show full text]
  • Calcareous Tubeworms of the Phanerozoic
    Estonian Journal of Earth Sciences, 2009, 58, 4, 286–296 doi: 10.3176/earth.2009.4.07 Calcareous tubeworms of the Phanerozoic Olev Vinna and Harry Mutveib a Department of Geology, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia; [email protected] b Department of Palaeozoology, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden; [email protected] Received 8 May 2009, accepted 8 June 2009 Abstract. Morphological similarities indicate that Palaeozoic problematic tubeworms, e.g. tentaculitids, cornulitids, microconchids, trypanoporids, Anticalyptraea, and Tymbochoos, form a monophyletic group. This group may also include hederelloids. Members of this group share affinities with lophophorates and their evolution could have partly been driven by predation. The extinction of Palaeozoic tubeworms in the Middle Jurassic was possibly at least partly caused by the ecological pressure by serpulid and sabellid polychaetes. The input of Palaeozoic tubeworms to the general ocean biocalcification system may have been smaller in the Ordovician to Jurassic than that of calcareous polychaetes in the Late Triassic to Recent. There seems to have been some correlation between the aragonite–calcite seas and the skeletal mineralogy of Triassic–Recent polychaete tubeworms. Key words: Phanerozoic, Polychaeta, Lophophorata, tubeworms, problematic fossils, calcification, biomineralization. INTRODUCTION 2008b, 2008c, 2008d). Therefore most likely these fossils belong to various Palaeozoic tubicolous problematica. In modern oceans hard substrates are often heavily The Palaeozoic to Middle Jurassic spirorbiform tube- encrusted by serpulid polychaetes. Serpulids were also worms, interpreted as the polychaete Spirorbis in the important encrusting organisms in the geological past older geological literature, have more recently been (ten Hove & van den Hurk 1993).
    [Show full text]
  • Cornulitids from the Upper Ordovician of Northwestern Russia
    Carnets Geol. 17 (12) E-ISSN 1634-0744 DOI 10.4267/2042/64289 Cornulitids from the Upper Ordovician of northwestern Russia Olev VINN1 Anna MADISON 2 Abstract: Four cornulitid species occur in the Rakvere Regional Stage in NW Russia. The new species Conchicolites rossicus is here described; it is the earliest known Conchicolites from the Ordovician of Baltica. The new species has very small tubes with sharp, strong and regular annulations. The diversity of cornulitids in the Rakvere Regional Stage at the Pechurki quarry is usual for the Upper Ordovician of Baltica. The cornulitids of Pechurki quarry encrusted hard organic substrates in a mud bottom (clay and carbonate clay) environment. Cornulites sterlingensis occurs both in the Upper Ordovician of North America and Baltica, which suggest a short distance between these two paleocontinents and/or similar environmental conditions. Key-words: • tubeworms; • tentaculitoids; • Katian; • Baltica; • shallow shelf; • paleobiogeography Citation: VINN O. & MADISON A. (2017).- Cornulitids from the Upper Ordovician of northwestern Russia.- Carnets Geol., Madrid, vol. 17, no. 12, p. 235-241. Résumé : Cornulitidés de l'Ordovicien supérieur du nord-ouest de la Russie.- Quatre espèces de cornulitidés sont présentes dans l'Étage Régional de Rakvere dans le nord-ouest de la Russie. La nouvelle espèce Conchicolites rossicus est décrite ici ; c'est le Conchicolites le plus ancien connu dans l'Ordovicien de Baltica. Il correspond à des tubes de très petite taille avec des anneaux, aigus et sail- lants, agencés à intervalles réguliers. La diversité des cornulitidés de l'Étage Régional de Rakvere dans la carrière de Pechurki est assez classique pour l'Ordovicien supérieur de Baltica.
    [Show full text]
  • Gigantism, Taphonomy and Palaeoecology of Basiloceras, a New Oncocerid Genus from the Middle Devonian of the Tafilalt (Morocco)
    Swiss Journal of Palaeontology (2019) 138:151–162 https://doi.org/10.1007/s13358-019-00182-8 (0123456789().,-volV)(0123456789().,- volV) REGULAR RESEARCH ARTICLE Gigantism, taphonomy and palaeoecology of Basiloceras, a new oncocerid genus from the Middle Devonian of the Tafilalt (Morocco) 1 1 2,3 Alexander Pohle • Christian Klug • Mischa Haas Received: 13 September 2018 / Accepted: 16 January 2019 / Published online: 31 January 2019 Ó Akademie der Naturwissenschaften Schweiz (SCNAT) 2019 Abstract The genus Basiloceras gen. nov. containing the two species B. goliath sp. nov. and B. david sp. nov. is described. It belongs to the Acleistoceratidae within the Oncocerida. Both species are from the Middle Devonian of the Tafilalt (Morocco). The genus exhibits a large interspecific size range between the small Eifelian B. david sp. nov. and the Givetian B. goliath sp. nov., the largest Devonian oncocerid currently known, altogether only second to some fragmentary remains of Calchasiceras from the Carboniferous of Russia. Several other large species are mainly known from the late Emsian of Bohemia and the Eifelian of Germany. The holotype of B. goliath sp. nov. contains numerous epicoles, trace fossils and shell debris, which are discussed in the context of its taphonomy. Compared to other oncocerids, Basiloceras is charac- terised by a short body chamber, which might be related to buoyancy regulation. In contrast to some older publications, we do not regard breviconic oncocerids with contracted aperture as benthic or nektobenthic animals, but instead, we think that they dwelled in the water column. Keywords Oncocerida Á Cephalopoda Á Gigantism Á Epicoles Á Taphonomy Á Buoyancy Introduction (Kro¨ger et al.
    [Show full text]
  • Shell Repair in Anticalyptraea (Tentaculita) in the Late Silurian (Pridoli) of Baltica
    Carnets de Géologie [Notebooks on Geology] - Article 2012/03 (CG2012_A03) Inconsistencies in proposed annelid affinities of early biomineralized organism Cloudina (Ediacaran): structural and ontogenetic evidences 1 Olev VINN 2 Michał ZATOŃ Abstract: Cloudina, an important Ediacaran index fossil, is considered as one of the earliest biominera- lizing organisms. Its biological affinities have not been fully resolved and phylogenetic links with both annelids and cnidarians have traditionally been suggested. Differences in tube morphology, ultra- structure and biomineralization suggest that Cloudina is not closely related to any recent skeletal anne- lid (e.g., serpulids, sabellids and cirratulids) and their skeletons are not homologous. The way of asexual reproduction in Cloudina resembles more that of cnidarians. The presence of a closed tube ori- gin (base) in Cloudina is also compatible with the hypothesis of an animal of cnidarian grade. Key Words: Cloudina; Annelida; Serpulidae; Cnidaria; Ediacaran; biomineralization. Citation: VINN O. & ZATOŃ M. (2012).- Inconsistencies in proposed annelid affinities of early biominera- lized organism Cloudina (Ediacaran): structural and ontogenetic evidences.- Carnets de Géologie [Note- books on Geology], Brest, Article 2012/03 (CG2012_A03), p. 39-47. Résumé : Incohérences dans les affinités supposées de l'organisme primitif biominéralisé Cloudina (Ediacaran) avec les annélides : preuves relevant de la structure et du développe- ment ontogénétique.- Cloudina, un important fossile édiacarien, est considéré comme l'un des pre- miers organismes biomineralisés. Ses affinités biologiques n'ont pas encore été entièrement élucidées : des relations phylogénétiques avec les annélides et les cnidaires sont habituellement envisagées. Des différences dans la morphologie, l'ultrastructure et la biominéralisation du tube suggèrent que Cloudina ne puisse être étroitement apparentée à aucun squelette d'annélides actuelles, qu'il s'agisse de serpu- lidés, de sabellidés ou de cirratulidés ; leurs squelettes ne sont pas homologues.
    [Show full text]