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In Pliocene Deposits, Antarctic Continental Margin (ANDRILL 1B Drill Core) Molly F
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln ANDRILL Research and Publications Antarctic Drilling Program 2009 Significance of the Trace Fossil Zoophycos in Pliocene Deposits, Antarctic Continental Margin (ANDRILL 1B Drill Core) Molly F. Miller Vanderbilt University, [email protected] Ellen A. Cowan Appalachian State University, [email protected] Simon H. H. Nielsen Florida State University Follow this and additional works at: http://digitalcommons.unl.edu/andrillrespub Part of the Oceanography Commons, and the Paleobiology Commons Miller, Molly F.; Cowan, Ellen A.; and Nielsen, Simon H. H., "Significance of the Trace Fossil Zoophycos in Pliocene Deposits, Antarctic Continental Margin (ANDRILL 1B Drill Core)" (2009). ANDRILL Research and Publications. 61. http://digitalcommons.unl.edu/andrillrespub/61 This Article is brought to you for free and open access by the Antarctic Drilling Program at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in ANDRILL Research and Publications by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Published in Antarctic Science 21(6) (2009), & Antarctic Science Ltd (2009), pp. 609–618; doi: 10.1017/ s0954102009002041 Copyright © 2009 Cambridge University Press Submitted July 25, 2008, accepted February 9, 2009 Significance of the trace fossil Zoophycos in Pliocene deposits, Antarctic continental margin (ANDRILL 1B drill core) Molly F. Miller,1 Ellen A. Cowan,2 and Simon H.H. Nielsen3 1. Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, TN 37235, USA 2. Department of Geology, Appalachian State University, Boone, NC 28608, USA 3. Antarctic Research Facility, Florida State University, Tallahassee FL 32306-4100, USA Corresponding author — Molly F. -
Corals (Anthozoa, Tabulata and Rugosa)
Bulletin de l’Institut Scientifique, Rabat, section Sciences de la Terre, 2008, n°30, 1-12. Corals (Anthozoa, Tabulata and Rugosa) and chaetetids (Porifera) from the Devonian of the Semara area (Morocco) at the Museo Geominero (Madrid, Spain), and their biogeographic significance Andreas MAY Saint Louis University - Madrid campus, Avenida del Valle 34, E-28003 Madrid, Spain e-mail: [email protected] Abstract. The paper describes the three tabulate coral species Caliapora robusta (Pradáčová, 1938), Pachyfavosites tumulosus Janet, 1965 and Thamnopora major (Radugin, 1938), the rugose coral Phillipsastrea ex gr. irregularis (Webster & Fenton in Fenton & Fenton, 1924) and the chaetetid Rhaphidopora crinalis (Schlüter, 1880). The specimens are described for the first time from Givetian and probably Frasnian strata of Semara area (Morocco, former Spanish Sahara). The material is stored in the Museo Geominero in Madrid. The tabulate corals and the chaetetid demonstrate close biogeographic relationships to Central and Eastern Europe as well as to Western Siberia. The fauna does not show any special influence of the Eastern Americas Realm. Key words: Anthozoa, biogeography, Devonian, tabulate corals, Morocco, West Sahara palaeogeographic province Coraux (Anthozoa, Tabulata et Rugosa) et chaetétides (Porifera) du Dévonien de la région de Smara (Maroc) déposés au Museo Geominero (Madrid) et leur signification biogéographique. Résumé. L´article décrit trois espèces de coraux tabulés : Caliapora robusta (Pradáčová, 1938), Pachyfavosites tumulosus Janet, 1965, et Thamnopora major (Radugin, 1938), le corail rugueux Phillipsastrea ex gr. irregularis (Webster & Fenton in Fenton & Fenton, 1924) ainsi que le chaetétide Rhaphidopora crinalis (Schlüter, 1880). Les spécimens, entreposés au Museo Geominero de Madrid, proviennent des couches givétiennes et probablement frasniennes de différents gisements de la région de Smara (Maroc, ancien Sahara espagnol), d’où elles sont décrites pour la première fois. -
A New Early Visean Coral Assemblage from Azrou-Khenifra Basin, Central Morocco and Palaeobiogeographic Implications Sergio Rodríguez1,2* , Ian D
Rodríguez et al. Journal of Palaeogeography (2020) 9:5 https://doi.org/10.1186/s42501-019-0051-5 Journal of Palaeogeography ORIGINAL ARTICLE Open Access A new early Visean coral assemblage from Azrou-Khenifra Basin, central Morocco and palaeobiogeographic implications Sergio Rodríguez1,2* , Ian D. Somerville3, Pedro Cózar2, Javier Sanz-López4, Ismael Coronado5, Felipe González6, Ismail Said1 and Mohamed El Houicha7 Abstract A new early Visean coral assemblage has been recorded from turbidite facies in the southern part of the Azrou- Khenifra Basin, northwest of Khenifra, central Morocco. The newly discovered Ba Moussa West (BMW) coral fauna includes Siphonophyllia khenifrense sp. nov., Sychnoelasma urbanowitschi, Cravenia lamellata, Cravenia tela, Cravenia rhytoides, Turnacipora megastoma and Pleurosiphonella crustosa. The early Visean age of the coral assemblage is supported by foraminiferal and conodont data, with the recognition of the basal Visean MFZ9 Zone. This confirms that the first transgression in the Azrou-Khenifra Basin was during the earliest Visean. The allochthonous coral assemblage was recovered from coarse-grained proximal limestone debris flow and turbidite beds within a fault- bounded unit, lying to the west of a thrust syncline containing upper Visean limestones. No evidence exists of the former early Visean shallow-water platform from which the corals were derived. All other in situ platform carbonate rocks around the southern margin of the Azrou-Khenifra Basin are probably of late Visean (Asbian–Brigantian) age. The early Visean Ba Moussa West coral fauna can be compared with that at Tafilalt in eastern Morocco, as well as in other Saharian basins of Algeria. Many of the genera and species in the Ba Moussa West assemblage are identical to those in NW Europe, with which it must have had marine connections. -
Geochronological and Paleomagnetic Constraints on the Lower Cretaceous Dalazi Formation from the Yanji Basin, NE China, and Its Tectonic Implication
minerals Article Geochronological and Paleomagnetic Constraints on the Lower Cretaceous Dalazi Formation from the Yanji Basin, NE China, and its Tectonic Implication Zhongshan Shen 1,2,3, Zhiqiang Yu 4,5,* , Hanqing Ye 1,2,3, Zuohuan Qin 6 and Dangpeng Xi 6 1 State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China; [email protected] (Z.S.); [email protected] (H.Y.) 2 College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China 3 Innovation Academy for Earth Science, Chinese Academy of Sciences, Beijing 100029, China 4 Key Laboratory of Vertebrate Evolution and Human Origin of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China 5 CAS Centre for Excellence in Life and Paleoenvironment, Beijing 100044, China 6 State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China; [email protected] (Z.Q.); [email protected] (D.X.) * Correspondence: [email protected] Abstract: The Lower Cretaceous Dalazi Formation in the Yanji Basin, eastern Jilin Province is of particular interest because it contains key fresh water fossil taxa, oil and gas resources, a potential terrestrial Albian–Cenomanian boundary, and regional unconformities. However, the lack of a Citation: Shen, Z.; Yu, Z.; Ye, H.; Qin, precise chronology for the non-marine strata has precluded a better understanding of the regional Z.; Xi, D. Geochronological and stratigraphic correlation and terrestrial processes. Here, we report magnetostratigraphic and U–Pb Paleomagnetic Constraints on the geochronologic results of a sedimentary sequence from the Xing’antun section in the Yanji Basin. -
A New Trachypsammiid Cnidarian from the Late Permian of Spitsbergen
POLISH POLAR RESEARCH 18 3-4 159-169 1997 Aleksander NOWIŃSKI Institute of Paleobiology Polish Academy of Sciences Twarda 51/55 00-818 Warszawa, POLAND A new trachypsammiid cnidarian from the Late Permian of Spitsbergen ABSTRACT: Starostinella nordica gen. et sp. n. is described from the uppermost Permian (Kapp Starostin Formation) of the Kapp Starostin (Isfjorden) in West Spitsbergen. The new genus is attributed to Trachypsammiidae Gerth - a family incertae sedis among Cnidaria. Members of the Trachypsammiidae have been previously associated with different higher rank taxa within the Cnidaria, or their skeletons were interpreted as a result of symbiosis of a cladochonoidal organism (Tabulata) with an indeterminate hydroid or stromatoporoid. S. nordica gen. et sp. n. seems to support the latter assumption. Hydrocoralla of S. nordica have a simpler structure than those of other Trachypsammiidae and are branching like those of Cladochonus. Their thick-walled, horn-shaped hydrocorallites are surrounded with a very thick cortical zone of sclerenchyme organized into trabecular microstructure. The proper corallite wall is fibro-radial in structure, sharply distinct from the outer cortical zone. Key words: Arctic, Permian, Cnidaria (Trachypsammiidae). Introduction The family Trachypsammiidae Gerth, to which the new genus Starostinella is here assigned, occupies an incertae sedis position among the Cnidaria. Its representatives have been variously included into Tabulata (Favositida, Aulo- porida), Octocorallia (Trachypsammiacea), or simply to Cnidaria without further indication of class nor order. A hypothesis was also put forward that the hydro coralla of Trachypsammiidae result from symbiosis of two skeletal organisms: a cladochonoidal organism (Tabulata) and an indeterminate stromatoporoid or a hydroid. -
Biostratigraphy
Biostratigraphy Geology 331 Paleontology The Grand Canyon of the Colorado River in Arizona Lithostratigraphic correlation between Grand Canyon, Zion, and Bryce Canyon national parks allows construction of a composite stratigraphic column. Lithostratigraphic correlation Grand Canyon, Zion Canyon, Bryce Canyon between Grand Canyon, Zion, and Bryce Canyon national parks Top of Navaho Ss. allows construction of a Top of Kaibab Ls. composite stratigraphic column. Zion Canyon National Park, Jurassic Sedimentary Rocks Jurassic Navaho Sandstone, Zion National Park, wind-blown cross-bedding. Bryce Canyon, Utah, Cretaceous sedimentary rocks Correlation • Determination of the equivalence of bodies of rock at different locations. There are two kinds of correlation: • Lithostratigraphic - matching up continuous formations. • Chronostratigraphic - matching up rocks of the same age. Usually done with fossils using biostratigraphy. Correlation • Over short distances lithostratigraphic correlation is the same as chronostratigraphic correlation. • Over medium distances they are not the same. • Over long distances only chronostratigraphic correlation can be used. Original Lateral Continuity: permits lithostratigraphic correlation – note the continuous beds Lithostratigraphic and Chronostratigraphic Relationships Sedimentary facies, and their subsequent rocks, are usually time-transgressive. http://www.geol.umd.edu/~tholtz/G331/lectures/331strat.html Sedimentary Facies Modern Barrier Island Time Lines Sedimentary Facies in the subsurface Wire line logs Time -
CNIDARIA Corals, Medusae, Hydroids, Myxozoans
FOUR Phylum CNIDARIA corals, medusae, hydroids, myxozoans STEPHEN D. CAIRNS, LISA-ANN GERSHWIN, FRED J. BROOK, PHILIP PUGH, ELLIOT W. Dawson, OscaR OcaÑA V., WILLEM VERvooRT, GARY WILLIAMS, JEANETTE E. Watson, DENNIS M. OPREsko, PETER SCHUCHERT, P. MICHAEL HINE, DENNIS P. GORDON, HAMISH J. CAMPBELL, ANTHONY J. WRIGHT, JUAN A. SÁNCHEZ, DAPHNE G. FAUTIN his ancient phylum of mostly marine organisms is best known for its contribution to geomorphological features, forming thousands of square Tkilometres of coral reefs in warm tropical waters. Their fossil remains contribute to some limestones. Cnidarians are also significant components of the plankton, where large medusae – popularly called jellyfish – and colonial forms like Portuguese man-of-war and stringy siphonophores prey on other organisms including small fish. Some of these species are justly feared by humans for their stings, which in some cases can be fatal. Certainly, most New Zealanders will have encountered cnidarians when rambling along beaches and fossicking in rock pools where sea anemones and diminutive bushy hydroids abound. In New Zealand’s fiords and in deeper water on seamounts, black corals and branching gorgonians can form veritable trees five metres high or more. In contrast, inland inhabitants of continental landmasses who have never, or rarely, seen an ocean or visited a seashore can hardly be impressed with the Cnidaria as a phylum – freshwater cnidarians are relatively few, restricted to tiny hydras, the branching hydroid Cordylophora, and rare medusae. Worldwide, there are about 10,000 described species, with perhaps half as many again undescribed. All cnidarians have nettle cells known as nematocysts (or cnidae – from the Greek, knide, a nettle), extraordinarily complex structures that are effectively invaginated coiled tubes within a cell. -
Biostratigraphy and Palaeobiology of Early Neoproterozoic Strata of the Kola Peninsula, Northwest Russia
Biostratigraphy and palaeobiology of Early Neoproterozoic strata of the Kola Peninsula, Northwest Russia JOAKIM SAMUELSSON Samuelsson, J.: Biostratigraphy and palaeobiology of Early Neoproterozoic strata of the Kola Peninsula, Northwest Russia. Norsk Geologisk Tidsskrift, Vol. 77, pp. 165-192. Oslo 1997. ISSN 0029-196X. Shales and siltstones from the Early Neoproterozoic K.ildinskaya, Volokovaya and Einovskaya Groups and the Skarbeevskaya Fonnation (Kildin Island, Sredni and Rybachi Peninsulas) and the Chapoma Fonnation (Tiersky Coast) on the Kola Peninsula, Northwest Russia yielded assemblages of moderately well-preserved organic-walled acid-resistant microfossils (acritarchs, and prob able cyanobacterial sheaths). The assemblages consist of cosmopolitan taxa recovered from various Early Neoproterozoic (Late and Terminal Riphean) settings in Scandinavia, Russia, Yakutia, North America and elsewhere. Among the recovered taxa, Lopho sphaeridium laufeldii Vida) 1976 comb. nov., Satka colonialica Jankauskas, Simia annulare (Timofeev) Mikhailovna, Tasmanites rifejicus Jankauskas, Valeria lophostriata Jankauskas and Vandalosphaeridium ?varangeri Vida! are regarded as the biostratigraphi cally most significant. One taxon, Trachysphaeridium laufeldi Vida) is transferred to Lophosphaeridium laufeldii (Vida!) Samuelsson comb. nov. The units examined herein are all considered to be Late Riphean in age and are correlated with other units of similar age in northem and southem Scandinavia, Svalbard, East Greenland and the southem Urals. Joakim Samuelsson, Uppsala University, Institute of Earth Sciences, Micropalaeontology, Norbyviigen 22, S-752 36 Uppsala, Sweden. Introduction Neoproterozoic strata worldwide (e.g. Vidal 1976a; Vidal During the Neoproterozoic, the Baltica palaeocontinent 1981a; Knoll 1982a, 1982b; Vidal & Siedlecka 1983; underwent major sedimentological, tectonic and palaeo Knoll 1984; Vidal 1985; Knoll et al. 1989; Jankauskas et geographical changes (Kumpulainen & Nystuen 1985; al. -
Progress to Extinction: Increased Specialisation Causes the Demise of Animal Clades Recei E : 3 O Em Er 015 P
www.nature.com/scientificreports OPEN Progress to extinction: increased specialisation causes the demise of animal clades receie: 3 oemer 015 P. Raia1, F. Carotenuto1, A. Mondanaro1, S. Castiglione1, F. Passaro1, F. Saggese1, accepte: 1 u 016 M. Melchionna1, C. Serio1, L. Alessio1, D. Silvestro2 & M. Fortelius3,4 Puise: 10 uust 016 Animal clades tend to follow a predictable path of waxing and waning during their existence, regardless of their total species richness or geographic coverage. Clades begin small and undiferentiated, then expand to a peak in diversity and range, only to shift into a rarely broken decline towards extinction. While this trajectory is now well documented and broadly recognised, the reasons underlying it remain obscure. In particular, it is unknown why clade extinction is universal and occurs with such surprising regularity. Current explanations for paleontological extinctions call on the growing costs of biological interactions, geological accidents, evolutionary traps, and mass extinctions. While these are efective causes of extinction, they mainly apply to species, not clades. Although mass extinctions is the undeniable cause for the demise of a sizeable number of major taxa, we show here that clades escaping them go extinct because of the widespread tendency of evolution to produce increasingly specialised, sympatric, and geographically restricted species over time. Most animal clades follow a predictable path in geographic commonness and taxonomic diversity over time1,2. Clades usually start within a very restricted range3, and then expand and diversify to occupy large stretches of Earth. Almost immediately afer this peak in success, they start declining in diversity and fnally go extinct1,2,4–6 (although a few may survive with as little diversity as one genus like sphenodonts, coelacanths, and nautiloids). -
Carboniferous Tabulate Corals from the Sardar Formation in the Ozbak-Kuh Mountains, East-Central Iran
Bull. Natl. Mus. Nat. Sci., Ser. C, 46, pp. 47–59, December 25, 2020 Carboniferous Tabulate Corals from the Sardar Formation in the Ozbak-kuh Mountains, East-Central Iran Shuji Niko1* and Mahdi Badpa2 1 Department of Environmental Studies, Faculty of Integrated Arts and Sciences, Hiroshima University, Higashihiroshima, Hiroshima 739–8521, Japan 2 Department of Geology, Payame Noor University of Qom, Qom, Iran *Author for correspondence: [email protected] Abstract Five species of tabulate corals are described from the Serpukhovian–Bashkirian (late early– early late Carboniferous) part of the Sardar Formation in the Ozbak-kuh Mountains, East-Central Iran. They are Michelinia flugeli sp. nov., late Bashkirian, Michelinia sp. indet., late Bashkirian, Donetzites mariae Flügel, 1975, late Serpukhovian, Syringopora iranica sp. nov., late Serpukhovian, and Multithe- copora sp. cf. M. huanglungensis Lee and Chu in Lee et al., 1930, late Serpukhovian to late Bashkirian. The Sardar tabulate coral fauna occurs from limestones that formed in Peri-Gondwana at the low lati- tudes of the southern hemisphere and faced the Paleo-Tethys Ocean. Except for a cosmopolitan species, closely related to comparable species with the fauna are reported from the Akiyoshi seamount chain, the South China Continent, and the Australian eastern Gondwana. Key words: Serpukhovian–Bashkirian, late early–early late Carboniferous, Favositida, Auloporida, Peri-Gondwana Introduction et al. (2006) separated its upper part from the for- mation as the Zaladu Formation that is correlative The Ozbak-kuh Mountains are a fault topography with the Gzhelian (late late Carboniferous) to Asse- in the Kashmar-Kerman Tectonic Zone (Stöcklin lian (early early Permian). -
Lab 8: Graptolites and Trace Fossils
Geos 223 Introductory Paleontology Spring 2006 Lab 8: Graptolites and Trace Fossils Name: Section: AIMS: This lab will introduce you to graptolites (Part A), and to a branch of paleontology known as ichnology (the study of trace fossils; Part B). By the end of Part A this lab you should be familiar with the basic anatomy of graptolites, and have an appreciation for how graptolites are used in the biostratigraphic zonation of the Lower Paleozoic. By the end of Part B of this lab you should be familiar with the basic ethological groups of trace fossils, and have an appreciation for how trace fossils can provide important paleoecological and paleoenvironmental information. PART A: GRAPTOLITES. Graptolites (Class Graptolithina) are an extinct group of colonial hemichordate deuterostomes, similar in morphology and life habit to the modern colonial pterobranch hemichordate Rhabdopleura. The graptolite colony consisted of many clonal zooids, each occupying a theca in the communal skeleton (the rhabdosome). The thecae formed in rows along branches of the rhabdosome called stipes. The rhabdosome was made of a non-mineralized, organic, non-chitinous protein called periderm. Graptolite colonies were either erect fan-like structures growing from the seafloor (most dendroid graptolites, ranging from the Middle Cambrian to the Late Carboniferous) or free-floating in the plankton (the commoner graptoloid graptolites, probably descended from dendroid ancestors and ranging from the Early Ordovician to the Early Devonian). Graptoloid graptolites are very important biostratigraphic zone fossils in Lower Paleozoic strata. 1 DENDROID GRAPTOLITES: A1: Dictyonema. Dendroid graptolite colonies formed fan-like structures with thecae-bearing stipes held apart by horizontal struts (dissepiments). -
Convolutional Neural Networks As an Aid to Biostratigraphy and Micropaleontology: a Test on Late Paleozoic Microfossils
PALAIOS, 2020, v. 35, 391–402 Research Article DOI: http://dx.doi.org/10.2110/palo.2019.102 CONVOLUTIONAL NEURAL NETWORKS AS AN AID TO BIOSTRATIGRAPHY AND MICROPALEONTOLOGY: A TEST ON LATE PALEOZOIC MICROFOSSILS RAFAEL PIRES DE LIMA,1,2 KATIE F. WELCH,1 JAMES E. BARRICK,3 KURT J. MARFURT,1 ROGER BURKHALTER,4 MURPHY CASSEL,1 AND GERILYN S. SOREGHAN1 1School of Geosciences, The University of Oklahoma, 100 East Boyd Street, RM 710, Norman, Oklahoma 73019, USA 2The Geological Survey of Brazil–CPRM, 55 Rua Costa, S˜ao Paulo, S˜ao Paulo, Brazil 3Department of Geosciences, Mail Stop 1053, Texas Tech University, Lubbock, Texas 79409, USA 4Sam Noble Museum, The University of Oklahoma, 2401 Chautauqua Ave., Norman, Oklahoma 73072, USA email: [email protected]; [email protected] ABSTRACT: Accurate taxonomic classification of microfossils in thin-sections is an important biostratigraphic procedure. As paleontological expertise is typically restricted to specific taxonomic groups and experts are not present in all institutions, geoscience researchers often suffer from lack of quick access to critical taxonomic knowledge for biostratigraphic analyses. Moreover, diminishing emphasis on education and training in systematics poses a major challenge for the future of biostratigraphy, and on associated endeavors reliant on systematics. Here we present a machine learning approach to classify and organize fusulinids—microscopic index fossils for the late Paleozoic. The technique we employ has the potential to use such important taxonomic knowledge in models that can be applied to recognize and categorize fossil specimens. Our results demonstrate that, given adequate images and training, convolutional neural network models can correctly identify fusulinids with high levels of accuracy.