439 research outputs found
Bolboforma (Protophyta,incertae sedis) im OligozÀn und MiozÀn des Mediterran und der Zentralen Paratethys
Aus oligozÀnen und miozÀnen Sedimenten im Ablagerungsraum der Zentralen Paratethys, aus
DSDP Bohrungen von Leg 42 A und ODP Leg 107 im Mediterran sowie aus AufschlĂŒssen in Algerien
und Mittelspanien werden Arten und Zysten von Bolboforma (Protophyta, incertae sedis)
nachgewiesen. Die publizierten Vorkommen wurden revidiert und in die Auswertung einbezogen.
Dadurch konnten die bisherigen Kenntnisse ĂŒber die stratigraphische und palĂ€oökologische
Verbreitung dieser wahrscheinlich planktonischen Mikrofossilgruppe im Zeitabschnitt OberoligozÀn
bis ObermiozÀn ergÀnzt werden. In der Zentralen Paratethys ist das OberoligozÀn und tiefere
UntermiozÀn (Egerien bis Eggenburgien) durch Bolboforma rotunda und B. spinosa gekennzeichnet.
Im höheren UntermiozÀn wurde Bolboforma nicht nachgewiesen. Sehr reiche Vorkommen
charakterisieren das MittelmiozÀn (Badenien) und gestatten eine Unterteilung in die B. reticulataund
die B. badenesis-Zone. Die im Atlantik dazwischen liegende, zeitlich sehr kurze B. danielsi-Zone
wurde hier und auch im Mediterran bisher nicht beobachtet. Mit der Reduktion der SalinitÀt ab dem
Sarmatien verschwinden Bolboformen aus der Paratethys. Im Mediterran wurde Bolboforma erst ab
dem MittelmiozÀn nachgewiesen. Die B. reticulata-, B. badenensis- und B. compressispinosa-Zonen sind
im MittelmiozÀn vorhanden. Im ObermiozÀn sind Nachweise von B. laevis und B. aculeata im
Tortonien sowie von B. subfragoris im Tortonien und Messinien zu erwĂ€hnen. FĂŒr Korrelationen wichtig
ist die Beobachtung der B. intermedia-Zone im unteren Messinien (NN lib) der Tyrrhenischen See,
sowie das Vorkommen von B. metzmacheri in AufschlĂŒssen Algeriens. Das faziesbrechende
Vorkommen von Bolboforma ist besonders hervorzuheben
Palaeoenvironmental reconstruction of the Sarmatian (Middle Miocene) Central Paratethys based on palaeontological and geochernical analyses of foraminifera, ostracods, gastropods and rodents
International audiencePaleoenvironmental changes in the upper Middle Miocene Central Parathetys were reconstructed by using qualitative and quantitative palaeontological analyses of foraminifera and ostracods, coupled with trace elemental (Mg/Ca) and stable isotope (delta(18)O and delta(13)C) analyses of their carbonate skeletons and of gastropod sheets. Mean annual air temperatures were estimated using the oxygen isotope composition of contemporaneous rodent teeth. The studied aquatic fossils come from two boreholes in the Zsambek basin (northern central Hungary), while the terrestrial ones are from localities in NE Hungary and E Romania. In the studied Sarmatian successions, three zones could be distinguished, based on palaeontological and geochemical results. At the Badenian/Sarmatian boundary, faunal diversity decreased markedly. In the lower zone a transgressive event culminated in a seawater incursion into the semi-open basin system of the Central Paratheys. Stable bottom-water temperature (similar to 15 degrees C) and variable salinites (20-22\%) are estimated for the Early Sarmatian Sea. The faunal changes (notably a strong reduction in biodiversity) occuring at the boundary between the lower and the middle zone can be explained by a sea-leval highstand with dysoxic conditions. A relative sea-level fall is documented at the end of this middle zone. After a short regressive event, a marine connection between the Paratethys and Mediterranean was established at the beginning of the upper zone. This is indicated by an increased microfaunal diversity and the re-appearance of marine Bademan ostracods and foraminifera, which are completely absent from the older Samatian series. During the upper zone, the temperatures and salmities are estimated to have fluctuated from 15 degrees C to 21 degrees C and from 15 parts per thousand to 43 parts per thousand, respectively
Bildung und kollektive Intelligenz heute
Bildung und kollektive Intelligenz heute.
Eine Untersuchung des Sprachspielers auf Tauglichkeit in einer Gesellschaft, die social media aus dem privaten ins öffentliche Leben ĂŒbertrĂ€gt.
Wie der Titel schon verrĂ€t, untersucht diese Diplomarbeit das Bildungsprinzip des Sprachspielers, das auf Norbert Meder zurĂŒckgeht, in der heutigen elektronisch vernetzten Welt. Besonderes Augenmerk wird auf Gesellschaftsschichten gelegt, die zum einen Vernetzung im Bereich des Gamings betrieben und sich zum anderen ĂŒber social media verbindet. Es wird dabei herausgestrichen, dass diese Formen der Vernetzung im Sinne von Johan Huizinga als eine kulturelle Entwicklung angesehen werden kann, die ihren Ursprung im Spiel hat. Anhand dieser Entstehung von Kultur werden Anzeichen von kollektiver Intelligenz, wie sie Pierre LĂ©vy dargestellt hat, in diesen Gesellschaftsgruppen aufgezĂ€hlt. Aus diesem Grund lautet die Forschungsfrage der Diplomarbeit:
Ist der Sprachspieler als Bildungsideal im Feld der MedienpĂ€dagogik fĂŒr eine Gesellschaft angemessen, die sich durch die Verwendung digitaler Medien tendenziell immer mehr durch kollektive Intelligenz auszeichnet?
Der erste Teil (2) der Arbeit beschĂ€ftigt sich mit den grundlegenden PhĂ€nomenen, die einen Einstieg in das Thema erleichtern sollen. So wird der allgemeine Bildungsbegriff mit Horkheimer und Humboldt genauer expliziert, mit dem Ergebnis, dass bedeutende PĂ€dagogen und Philosophen sehr oft das gleiche Muster bei der Definition ihrer Bildungstheorien benutzten. Nachdem dies festgestellt wurde, folgt eine kleine EinfĂŒhrung in das Feld der MedienpĂ€dagogik sowie der Game Studies, um einen wissenschaftlichen Kontext fĂŒr die im zweiten Teil beschriebenen, spezifischen PhĂ€nomene herstellen zu können. Als populĂ€res Medium wird in der Folge Twitter als Werkzeug fĂŒr viele Gesellschaftsschichten beschrieben, um am Ende des ersten Teils einen kurzen Umriss der IdentitĂ€t und ihren VerĂ€nderungen im elektronischen Raum zu geben.
Im zweiten Teil (3) wird gleich zu Beginn mit Huizinga und Scheuerl das Spiel in anthropologischer und pĂ€dagogischer Hinsicht ausgewiesen, gefolgt von der Theorie des Sprachspielers nach Norbert Meder. Als dritter, wichtiger Punkt wird die kollektive Intelligenz, eine Theorie von Pierre LĂ©vy, angegeben und dargestellt. AnschlieĂend wird der Bereich des Gamings, mit besonderem Augenmerk auf kreative Medienprodukte von Gamern und deren Austausch ĂŒber das Internet, einer genaueren Untersuchung unterzogen. Der zweite Teil schlieĂt mit einer Darstellung von politischem Protest der jĂŒngeren Zeit, der besonders ĂŒber soziale Medien mitorganisiert wurde. Hier wird ein besonders die unibrennt-Bewegung und die Mobilisierung der Massen ĂŒber Twitter erörtert.
Der dritte Teil der Diplomarbeit (4) versucht nun die einzelnen PhĂ€nomene miteinander zu vergleichen und mögliche Ăhnlichkeiten und Ableitungen zu den Themen unibrennt, Spiel, Game bzw. ludic artefacts, kollektive Intelligenz und dem Sprachspieler zu finden. Der letzte Punkt dieses Abschnitts betrachtet die Möglichkeiten der Theorie des Sprachspielers in einer Gesellschaft gĂŒltig zu sein, die sich durch den Gebrauch sozialer Medien oder grundsĂ€tzlich durch Vernetzung im Internet auszeichnet. Als roter Faden sollte hier die Entwicklung der Vernetzung zuerst im spielerischen Bereich erkennbar sein, um in der Folge aus dem privaten Raum herauszutreten und im politischen Ausdruck ein Teil einer kulturellen Entwicklung zu sein. Die Anzeichen der kollektiven Intelligenz in den Gruppen Gamer und unibrennt werden dargestellt und es wird versucht aus dieser Ableitung einen gemeinsamen Nenner in Form des Sprachspielers zu finden.
Die Ergebnisse und SchlĂŒsse sind in der Folge im nĂ€chsten Punkt (5) nachzulesen, der die Forschungsfrage noch einmal ins GedĂ€chtnis ruft und sie zu beantworten versucht
Revised Middle Miocene datum for initial marine fl ooding of North Croatian Basins (Pannonian Basin System, Central Paratethys)
The Pannonian Basin System (PBS) originated during the Early Miocene as a result of extensional processes between the Alpine-Carpathian and the Dinaride Orogenic Belts. The Paratethys Sea flooded the new basins successively during the Karpatian (late Burdigalian, Early Miocene) and the Early Badenian (middle Langhian, Middle Miocene). The North Croatian Basins (NCB) occupied the south-western margin of the PBS and the Central Paratethys Sea.
Their initial marine flooding has until now been dated as Karpatian in age. The transgression into the NCB invaded a lacustrine environment, representing the northern prolongation of the vast Dinaride Lake System extending southwards as far as the Adriatic Plate. We reinvestigate two sections from opposite margins of the NBS â from Mt. Medvednica in the west and from Mt. PoĆŸeĆĄka in the east, including the corresponding lowermost marine Miocene deposits, in order to critically examine the Karpatian datum. Our new biostratigraphic data, integrating calcareous nannoplankton, planktic and benthic foraminifera, diatom and mollusc records, have substantially revised the previous interpretation. The presence of a calcareous nannoplankton assemblage of the NN5 Zone and the planktic and benthic foraminifera of the regional Lower Lagenidae Zone now place the transgression into the main Early Badenian
transgressive pulse of Central Paratethys. Consequently, the initial marine transgression correlates accurately with the middle part of the Early Badenian, which is more than 2 m.y. younger than the previously inferred datum, and at least 1 m.y. younger than the lower boundary of the Badenian and the Middle Miocene, respectively. Finally, the basal lacustrine infill of the NCB, previously dated as Ottnangian (middle Burdigalian, Early Miocene) and continuously grading into marine deposits, has also to be reconsidered as Early Badenian
Badenian evolution of the Central Paratethys Sea : paleogeography, climate and eustatic sea-level changes
The Miocene Central Paratethys Sea covered wide areas of the Pannonian Basin System, bordered by the mountain chains of the Alps, Carpathians and Dinarides. The epicontinental sea spread not only in the back-arc basin area, but flooded even the Alpine-Carpathian Foredeep, situated along the front of gradually uplifting mountains. The Early Badenian (early Langhian) transgressions from the Mediterranean toward the Central Paratethys realm, via Slovenia and northern Croatia (Transtethyan Trench Corridor or Trans Dinaride Corridor) flooded the Pannonian Basin and continued along straits in the Carpathian Chain into the Carpathian Foredeep. The isolation of eastern parts of the Central Paratethys at the end of this period (late Langhian) resulted in the "Middle Badenian" salinity crisis. Thick evaporite sediments, above all halite and gypsum were deposited in the Transcarpathian Basin, Transylvanian
Basin and Carpathian Foredeep. During the Late Badenian (early Serravallian), the latest full marine flooding covered the whole back-arc basin and a great part of the foredeep. The main problem is to create a model of sea connections during that time, because some authors consider the western Transtethyan Trench Corridor (Trans Dinaride Corridor) closed and there is no evidence to prove a supposed strait towards the Eastern Mediterranean. A proposed possibility is a connection towards the Konkian Sea of the Eastern Paratethys. The Badenian climate of the Central Paratethys realm can be characterized as fairly uniform, reflecting the stable subtropical conditions of the Miocene Climatic Optimum. No considerable changes in terrestrial ecosystems were documented. Nevertheless, evolution of steep landscape associated with rapid uplift of the East Alpine and Western Carpathian mountain chains (including high stratovolcanoes) caused development of vertical zonation of dry land and consequently close occurrence of different vegetation zones in a relatively small distance during this time. In the Central Paratethys Sea a slight N-S climatic gradient seems to be expressed already from the Early Badenian, but a biogeographic differentiation between basins in the North and South starts to become more prominent first during the Late Badenian, when a moderate cooling of the seawater can also be documented. The Late Badenian sea-level highstand coincides with the appearance of stress factors such as stratification of the water column and hypoxic conditions at the basin bottom in the whole area. Taking into account all bioevents and changes of paleogeography in the Central Paratethys realm, we can very roughly correlate the Early (and "Middle") Badenian with the eustatic sea-level changes of TB 2.3, TB 2.4 or Bur5/Lan1, Lan2/Ser1 and the Late Badenian with TB 2.5 or Ser2 cycles (sensu Haq et al. 1988; Hardenbol et al. 1998). Generally, we can assign the Early Badenian transgressions to be controlled by both, tectonics (induced mainly by back-arc basin rifting) and eustacy, followed by forced regression. The Late Badenian transgression and regression were dominantly controlled by sea-level changes inside the Central Paratethys realm
Insights in the exhumation history of the NWZagros frombedrock and detrital apatite fission-track analysis: evidence for a long-lived orogeny
We present the Âąrst Âąssion-track (FT) thermochronology results for theNWZagrosBelt (SWIran) in
order to identify denudation episodes that occurred during the protracted Zagros orogeny. Samples
were collected from the two main detrital successions of the NWZagros foreland basin: the
Palaeocene^early Eocene Amiran^Kashkan succession and theMiocene Agha Jari and Bakhtyari
Formations. In situ bedrock samples were furthermore collected in the Sanandaj-Sirjan Zone. Only
apatite Âąssion-track (AFT) data have been successfully obtained, including 26 ages and11track-length
distributions. Five families of AFTages have been documented from analyses of in situ bedrock and
detrital samples: pre-middle Jurassic at 171 and 225Ma, early^late Cretaceous at 91Ma,
Maastrichtian at 66Ma,middle^late Eocene at 38Ma and Oligocene^early Miocene at
22Ma.The most widespread middle^late Eocene cooling phase, around 38Ma, is documented
by a predominant grain-age population in Agha Jari sediments and by cooling ages of a granitic
boulder sample. AFTages document at least three cooling/denudation periods linked to major
geodynamic events related to the Zagros orogeny, during the lateCretaceous oceanic obduction event,
during the middle and late Eocene and during the earlyMiocene. Both late Cretaceous and early
Miocene orogenic processes produced bending of the Arabian plate and concomitant foreland
deposition. Between the two major ÂŁexural foreland episodes, the middle^late Eocene phase mostly
produced a long-lasting slow- or nondepositional episode in the inner part of the foreland basin,
whereas deposition and tectonics migrated to theNE along the Sanandaj-Sirjan domain and its
Gaveh Rud fore-arc basin. As evidenced in this study, the Zagros orogeny was long-lived and multiepisodic,
implying that the timing of accretion of the diÂĄerent tectonic domains that form the Zagros
Mountains requires cautious interpretation
Reconstructing ancient Mediterranean crossroads in Deronectes diving beetles
[Aim] To reconstruct the evolutionary history of a genus of freshwater beetle with a pan-Mediterranean distribution, to test classic hypotheses which proposed a Miocene origin for groups with high biodiversity in the Iberian and Anatolian peninsulas.[Location] Mediterranean basin.[Methods] We sequenced four mitochondrial and one nuclear gene from 51 specimens of 30 of the c. 60 extant species of Deronectes (Dytiscidae), all typical of mid-mountain streams from North Africa and Iberia over most of Europe to the Middle East. We used maximum likelihood, Bayesian probabilities with an a priori evolutionary rate and a dispersalâextinctionâcladogenesis model to reconstruct their biogeographical history.[Results] Deronectes has two major lineages which originated in the mid Miocene; one including mostly eastern and another mainly western and central Mediterranean species. From these two areas, range expansions, mainly at the end of the Miocene and beginning of the Pliocene, resulted in the many species groups and some of the extant species of the genus. Most of the current diversity and distributions are, however, of Plio-Pleistocene origin, particularly in widespread European species.[Main conclusions] In line with traditional hypotheses, we found an ancient division between eastern and western Mediterranean lineages of Deronectes, likely resulting from the isolation of Europe west of the Alps from the Balkans and Anatolia during the early-middle Miocene. The history of the genus was strongly influenced by major geological and climatic events, with successive cycles of fragmentation and subsequent eastward and westward range expansions, resulting in a steady accumulation of species across the basin. Most of these range movements took place through the north side of the Mediterranean, with only local displacements in the south during the Messinian salinity crisis and a recent (Pleistocene) colonization of the Italian Peninsula, which remained largely submerged through most of the genusâ evolutionary history.D.G.V. has a FPI PhD grant from the Spanish Government. This work has been partly funded by projects CGL2010-15755 and CGL2013-48950-C2-1-P to I.R.Peer reviewe
Lithistid sponges from submarine caves in the Mediterranean: taxonomy and affinities
Several lithistid sponges are described from Mediterranean caves occurring in the northwestern and Adriatic basins. In the Corallistidae, Neoschrammeniella bowerbanki and Neophrissospongia nolitangere are recorded for the first time from the Mediterranean, whereas Neophrissospongia radjae n. sp. and Neophrissospongia endoumensis n. sp. are described as new. In the Theonellidae, the common sponge previously identified as Discodermia polydiscus is described as Discodermia polymorpha n. sp. Fossil specimens from the 3PP cave are tentatively attributed to Neoschrammeniella bowerbanki. The distribution and affinities of this lithistid fauna are discussed
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