BazTech - Yadda

1

The succession of ammonites of the genus Amoeboceras in the Upper Oxfordian – Kimmeridgian of the Nordvik section in northern Siberia

Rogov M., Wierzbowski A.

Volumina Jurassica

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2009

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Vol. 7, no. 1

147-156

EN

A collection of ammonites of the genus Amoeboceras located carefully in the section of Nordvik Peninsula in northern Siberia has enabled recognition of the standard Boreal ammonite zones of the Upper Oxfordian and Kimmeridgian. The recognition of the standard Amoeboceras zones, well known in NW Europe and the Barents Sea area, in northern Siberia indicates the uniform character of the Late Oxfordian and Kimmeridgian ammonite faunas across the whole Boreal Province. Some comments on the occurrence of Boreal oppeliids of the genus Suboxydiscites in the studied section are also given.

2

The Oxfordian ammonite genus Passendorferia Brochwicz Lewiński and the Tethyan subfamily Passendorferiinae Meléndez: origin and palaeobiogeography

Mendez G., Atrops F., Bello J., Brochwicz-Lewiński W., Darpa C., Fozy I., Perez-Urresti I., Ramajo J., Sequeiros L.

Volumina Jurassica

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2009

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Vol. 7, no. 1

113-134

EN

The Oxfordian ammonite group Passendorferiinae (known as "Mediterranean perisphinctids") forms a group of perisphinctids characterized by strongly evolute serpenticone coiling and subcircular to subquadrate whorl section, and forms a lateral divergent branch of the main stem Perisphinctidae. They originated probably from Late Callovian Grossouvriinae (Alligaticeras) and spread mainly in the Mediterranean (Tethyan) Province along the southern margin of Tethys, occasionally reaching the outer areas of epicontinental platforms. Their particular morphological features make them somewhat homoeomorphic with Tethyan Kimmeridgian Nebrodites. The phyletic link might be represented by the genus Geyssantia Meléndez, known from the Late Oxfordian Planula Chronozone. Separate biogeographic distribution in relation to the Perisphinctinae might reflect a progressive differentiation of western Tethyan faunas at the Callovian-Oxfordian boundary and at the onset of the Middle Oxfordian Transversarium Chronozone. Their rapid evolution gives them a biostratigraphic value similar to that of the Perisphinctinae. At the turn of the Middle-Late Oxfordian they gave rise to early Ataxioceratinae (Orthosphinctes), which replaced the Perisphinctinae in epicontinental areas, and colonised the marginal epicontinental blocks of northern Tethys. The taxonomy of this group is based upon the recognition of sexual dimorphism, using a single generic and specific name for both (M) and (m), and hence rejecting the use of former subgeneric ames for both dimorphs. A new species within this line: Passendorferia nodicostata sp. nov. from the Plicatilis Biozone (Paturattensis Subbiozone) is defined and described for the first time.

3

The ammonite faunas of the Callovian-Oxfordian boundary interval in Europe and their relevance to the establishment of an Oxfordian GSSP

Page K., Melendez G., Wright J.

Volumina Jurassica

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2009

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Vol. 7, no. 1

89-99

EN

At Moenkopi Wash along the Ward Terrace escarpment of northern Arizona strata of the upper Dinosaur Canyon Member of the Moenave Formation contain sedimentary structures we interpret as casts of tetrapod burrows. Sandstone casts and in situ burrows occur concentrated in two horizons that extend several hundred meters along the Ward Terrace escarpment. The structures, hosted in beds of eolian sandstone, form interconnecting networks of burrows that branch at right angles. Individual burrow casts have sub-circular cross sections and consist of nearvertical tunnels and horizontal to low-angle galleries that connect to larger chambers. Most burrow casts measure 5 to 15 cm in diameter, are filled by sandstone of similar grain size as the host rock, and have walls that are unlined and lack external ornamentation. Bedding plane exposure of the lower horizon reveals that the density of burrows exceeds 30 vertical tunnels per square meter. One exposure in the upper horizon reveals burrows concentrated in a mound-like structure with 1 m of relief. Rhizoliths, distinguished from burrows by their typical smaller diameters, calcareous infilling, and downward branching, co-occur with these burrows in the upper horizon. The fossil burrows in the Moenave Formation appear to have been constructed by a fossorial tetrapod with social behavior similar to the modern Mediterranean blind mole-rat. Although no skeletal remains are associated with the burrows, the fossil record suggests that the most likely producers of the Moenave burrows were tritylodontid cynodonts.

4

Małe otwornice "eocenu numulitowego" Tatr-stratygrafia i paleośrodowisko

Olszewska B.

Przegląd Geologiczny

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2009

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Vol. 57, nr 8

703-703

EN

Shallow-water carbonate sediments of the so called "Nummulitic Eocene" of the Tatra Mts. yield numerous large foraminifera as well as abundant and diversified assemblages of small foraminifera. Both benthic and planktic species indicate the late Bartonian-Priabonian age of the "Nummulitic Eocene". Paleoenvironmental analysis of the identified assemblages demonstrated their correlation with the Arni’s sedimentological model of the shallow-water carbonate sediments. The affiliations of foraminiferal faunas with the bioprovince of the Mediterranean Tethys have also been indicated.

5

Molluscan immigrations via biogeographical ecotone of the Middle Russian Sea during the Jurassic

Rogov M., Zakharov V., Kiselev D.

Volumina Jurassica

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2008

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Vol. 6, no. 1

143-152

EN

Patterns of molluscan immigration via the biogeographical ecotone zone of the Middle Russian Sea during the Middle – Late Jurassic have been studied in detail. Firstly, the migration routes and ranges of recent molluscs are briefly reviewed, with some comments about their applicability to the Jurassic. Secondly, the migrational events have been classified by their direction, duration and intensivity. We recognize two main types of immigration by their direction (unidirectional and multidirectional) and by their intensity (mass immigrations and isolated strayings). Recent progress in infrazonal ammonite biostratigraphy leads us to the more precise recognition of paleobiogeographical events and to the understanding of the immigration patterns that can produce more precise correlations.

6

Nanoplankton wapienny górnokredowych facji pelagicznych jednostki podśląskiej polskich Karpat fliszowych

Jugowiec-Nazarkiewicz M.

Biuletyn Państwowego Instytutu Geologicznego

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2007

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nr 426

53-70

PL

W pelagicznych osadach jednostki podśląskiej (marglach węglowieckich, marglach typu frydeckiego, marglach żegocińskich, piaskowcach z Rybia) oraz w marglach bakulitowych jednostki skolskiej i marglach z Bonarki występujących na monoklinie śląsko-krakowskiej (odsłonięcie Bonarka w Krakowie) stwierdzono liczne formy nanoplanktonu wapiennego wieku kampan-mastrycht. Wyznaczono poziomy nanoplanktonowe, określając wiek badanych osadów. W marglach bakulitowych, nazywanych też marglami z Węgierki, występujących w jednostce skolskiej, odnotowano podobny skład i charakter nanoplanktonu wapiennego jak w szarych marglach typu frydeckiego występujących w jednostce podśląskiej w zachodniej części Karpat. W badanych osadach jednostki podśląskiej nie stwierdzono ciągłego przejścia sedymentacyjnego między osadami mastrychtu i danu. Badania nanoplanktonu potwierdziły istnienie połączenia między strefą borealną i tetydzką na obszarze polskich Karpat zewnętrznych w kampanie i mastrychcie, o czym świadczy obecność w próbkach form nanoplanktonu uważanych za typowo borealne.

EN

In pelagic sediments of the Subsilesian Unit (Węglówka marls, Frydek-type marls, Żegocina marls and Rybie sandstones) and in the bakulit marls from the Skole Unit, and in marls from Bonarka in Silesian-Cracow Monocline many forms of calcareous nannoplankton of Campanian-Maastrichtian age were noted. Distinguishing of several nannoplankton assemblage zones allowed for more detailed time resolution of the studied sediments. Existing of the connection between the boreal and Tethyan realms in Polish Outher Carpathians during Campanian/Maastrichtian has been confirmed. Calcareous nannoplankton of the bakulit marls (Skole Unit) appeared similar to that from the Frydek-type marls (Subsilesian Unit). No continuous transition between sediments of the Maastrichtian and Danian within the studied Subsilesian Unit has been stated. Transition between Boreal and Tethyan realms on the Polish Outher Carpathians area, during Campanian and Maastrichtian age are confirmed.

7

Otwornice warstw cieszyńskich z obszaru Pogórza Cieszyńskiego (Karpaty zewnętrzne)

Szydło A.

Biuletyn Państwowego Instytutu Geologicznego

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2005

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nr 415

59-99

PL

W warstwach cieszyńskich odnotowano liczne otwornice bentoniczne wieku tyton-hoteryw. Generalnie ich liczebność i zróżnicowanie taksonomiczne zmniejszały się podczas depozycji tych osadów. Zubożenie zespołów otwornicowych było związane z transformacją geotektoniczną basenu karpackiego (cieszyńskiego) i ewolucją ówczesnych środowisk na przełomie jury i kredy. Analizy morfogrupowa i tafofacjalna wykazały, iż basen ewoluował od marginalnego i szelfowego zbiornika do otwartego basenu morskiego. Proces ten udokumentowała sukcesja ośmiu zespołów otwornicowych. Początkowo dominowały w nich wapienne otwornice bentoniczne znane z szelfowych i pararafowych środowisk basenów epikontynentalnych i morskich. Na przełomie jury i kredy zostały one wyparte przez głębokomorskie otwornice krzemionkowe. Pierwsza grupa wapiennych otwornic miała charakter allochtoniczny i była związana z końcową fazą regresji morza. Odmienna autochtoniczna mikrofauna pojawiła się z początkiem cyklu regresywno-transgresywnego. W tym czasie, przy nadal utrzymującym się niskim poziomie morza, doszło do wyraźnego pogłębienia zbiornika cieszyńskiego. Następstwo omawianych zespołów otwornic określa przynależność paleobiogeograficzną badanego fragmentu zbiornika karpackiego, który stał się integralną częścią oceanu tetydzkiego już we wczesnej kredzie.

EN

Numerous benthic foraminifers are noted in the Cieszyn Beds. Generally their number and taxonomic variability decreased during the sedimentation of these deposits. The impoverishment of foraminiferal assemblages, which corresponded with geotectonic transformation of the Carpathian (Cieszyn) Basin and evolution of the contemporary environments was noted at the turn of Jurassic-Cretaceous. Morphogroup and taphofacial analyses suggest that this basin evolved from narrow, shelf basin into open marine basin. Succession of foraminiferal assemblages has evidenced this process. At the beginning these assemblages contained calcareous benthic forms, which were known from shelf and para-reef environments of epicontinental and marine basins. At the Jurassic-Cretaceous boundary these ones were replaced by deep-water siliceous foraminifers. The first group of the mentioned foraminifers comprised mainly allochthonous forms, which occurred at the end of the regression of the sea. Autochthonous microfauna, al-though differing, appeared at the beginning of transgression cycle. At this time the basin was deepening while a level of the sea was as low as before. The sequence of the studied foraminiferal assemblages is related to paleobiogeographical position of the Cieszyn Basin, which finally became an integral part of the Tethyan bioprovince at the Early Cretaceous.