IN SEARCH OF THE EGGENBURGIAN – OTTNANGIAN BOUNDARY AT THE SOUTHEASTERN MARGIN OF THE BOHEMIAN MASSIF (LOWER AUSTRIA)

At the south-eastern margin of the Bohemian Massif in Lower Austria Eggenburgian to Ottnangian sediments are widespread. In the wider surroundings of Eggenburg nearshore clastic deposits of the upper Eggenburgian (Kühnring Mb., Burgschleinitz Fm., Gauderndorf Fm.) occur, which are discordantly overlain by shallow marine sublittoral bioclastic limestone of the Zogelsdorf Fm. Due to the ongoing transgression the Zogelsdorf Fm. shows a fining and deepening upward succession, passing upsection and laterally into marine clays and marls of the Zellerndorf Fm.Two completely cored logs from Limberg and Pulkau show this sedimentary succession above the crystalline basement. As in many outcrops, in the well Limberg KB2 on top of the Burgschleinitz Fm. a transgressional conglomerate occurs at the base of typical Zogelsdorf Fm. followed by pelites of the Zellerndorf Fm. The well Pulkau S1 exhibits between clastics of the Burgschleinitz Fm. and sands and limestone of the Zogelsdorf-Fm. a 4.5 m pelitic sequence with two tuffitic horizons. Between those notdateable tuffitic clays, badly sorted gravelly and sandy clay with molluscs like Granulolabium plicatum, Ostrea digitalina, Perna aquitanica, Cerastoderma edule, Taras rotundatus, Tellina planata, Cordiopsis incrassatus, Turritella sp., and Natica sp. indicates a deepening upward lagoonal environment. In dark gray fine bedded silty clays above thin shelled bivalves (Cardiidae, Veneridae, Lucinidea) and gastropods (Turritella eryna, Granulolabium plicatum) also point to shallow marine lagoonal conditions. This pelitic sequence is concordantly overlain by sands and sandy limestone of the Zogelsdorf Fm. and silty clay of the Zellerndorf Fm.Calcareous nannoplankton associations from the Burgschleinitz Fm. in Limberg KB2 can be correlated by Triquatrorhabdulus carinatus and Helicosphaera ampliaperta with the upper part of NN2. Sediments from the Zogelsdorf Fm. in the lower part of Limberg KB2 can be assigned to NN2/NN3 by H. ampliaperta and T. carinatus. Assemblages with H. ampliaperta and Reticulofenestra excavata in the lowermost part of the Zellerndorf Fm. in Pulkau S1 point to NN3.The successions in both wells show at the base upper Eggenburgian marine deposit (Burgschleinitz Fm.) followed by a regressional phase and a renewed transgression initiating the deposition in lagoonal facies in Pulkau S1. This regression presumably correlates with the main regional hiatus at the base of the Zogelsdorf Fm. and can be consequently correlated with the 3rd Order Sequence Stratigraphic Boundary Bur 3

Pedological and geochemical investigations at the „Red Outcrop“ of Langenlois (Lower Austria)

In einem Aufschluss von Löss-Paläoboden-Sequenzen über Rehberger Amphibolit NW von Langenlois wurden sechs Bodenprofile (Lois 1 bis Lois 6) beprobt und pedologisch, mineralogisch und geochemisch analysiert. Am Profil Lois 7 wurden bodenmikromorphologische Untersuchungen durchgeführt. Zwei Bodenprofile (Lois 1 und 2) haben sich über Amphibolit entwickelt, zwei über einer Amphibolit/Marmor-Wechsellagerung (Lois 5 und 6) und drei Bodenprofile sind Sequenzen von polyzyklischen Paläoböden mit fossilen Bodenhorizonten ohne unterlagerndes kristallines Gestein (Lois 3, 4 und 7). In den Profilen Lois 1–4 und Lois 7 konnten intensive Karbonatanreicherungen beobachtet werden. Diese hohen Mengen an Karbonat können nicht Produkt einer rezenten Bodenbildung sein, sondern sprechen für eine Infiltration von ursprünglich das Profil überlagernden kalzitreichen Sedimenten (Löss), die erodiert wurden. Zudem wurde in Profil Lois 2 ein Kalksinter angetroffen. Dieser Kalksinter könnte aus der Verwitterung der im Profil Lois 6 aufgeschlossenen Marmorlagen stammen. Die Kalksinter-Schicht scheint die Stoffflüsse zwischen unterliegendem Gestein und Solum in den Profilen Lois 1 und 2 mehr oder weniger zu unterbinden, was auch durch die Ergebnisse der geochemischen Analytik unterstrichen wird. In den fossilen Horizonten wurden auch ältere Anzeichen von Tonverlagerung in Form von Tonkutanen über den Aggregaten und darüber hinaus leichte Pseudovergleyungserscheinungen angetroffen. Die mächtigen Profile ohne aufgeschlossenes Grundgebirge (Lois 3, 4 und 7) weisen mehrere polyzyklische Sedimentationsphasen und dadurch mehrere Generationen von fossilen Horizonten auf. Aufgrund der bodenmikromorphologischen Analyse können die Böden vom „Roten Aufschluss“ altersmäßig im unteren bis mittleren Pleistozän oder älter angesiedelt werden.researc

Is this settlement intersected by a ditch? A comparison between magnetic prospection data, ALS data, and archaeological and geological excavation results from the Early Bronze Age fortified hilltop settlement of Ratzersdorf, Lower Austria

In this case study we present preliminary results from a joint analysis of magnetometry data, remote sensing data, and excavation results generated in the course of research on the Early Bronze Age fortified hilltop settlement of Ratzersdorf/Am Dachsgraben in Lower Austria. In an effort to evaluate the interpretive potential of each data set we conclude that a combined analysis of all available data is essential for a comprehensive understanding of anthropogenic and natural features and formation processes. At the Ratzersdorf site specifically, the visibility of both anthropogenic and geological structures in the magnetometry data demonstrates the importance of the combination of complementary data for the verification or falsification of preliminary interpretive ideas

SPECTACULAR INSIGHTS INTO ESTUARINE TO SHALLOW MARINE SEDIMENTS OF THE KARPATIAN (LOWER MIOCENE) IN THE KORNEUBURG BASIN (LOWER AUSTRIA)

The Korneuburg Basin in Lower Austria, about 18 km north of Vienna, is a ca 20 km long and at most 7 km wide asymmetric pull-apart basin formed within the Alpine-Carpathian thrustbelt during last Alpine movements in the Karpatian (late Early Miocene). During the construction of the S1 motorway south of Stetten a ca 1.8 km long section between the Tradenberg tunnel and the city of Korneuburg was geologically documented in detail (fig. 1). A flysch-elevation in the area of profile E (fig. 1) divides the section in an eastern (profiles A, F) and a western part (profiles G, D, D1, B, C1, C) causing an increasing number of faults in the Miocene sediments towards the vicinity of the flysch. In the western part constantly 20° to 30° westward dipping marl, marly silts and fine to medium sands, in some parts with intercalations of lignite and coaly clay were cropping out, whereas in the eastern part the westward dipping of similar sediments is changing to an eastward nearby the flysch high.Rich fossil content documents sedimentation in mudflats, coastal swamps and shallow sublittoral settings within an estuary. Autochthonous Lower Miocene nannofossils represented by stratigraphical important forms like Helicosphaera ampliaperta Bramlette et Wilcoxon, 1967, H. carteri (Wallich 1877) Kamptner 1954, Reticulofenestra excavata Lehotayova, 1975, Sphenolithus cf. heteromorphus Deflandre 1953, indicating nannoplankton Zone NN4 (Martini 1971). The mollusc fauna documents changing environmental conditions along the sampled transect. Nearby terrestrial habitats and freshwater influence are indicated by planorbids, hydrobiids and Melanopsis impressa. An enormous biodiversity with more than 650 taxa was documented from these paleoenvironments, allowing also precise climatic reconstruction from palynologic data: within subtropical climatic conditions intertidal to very shallow subtidal marine environments and brackish water with Agapilia pachii, Granulolabium plicatum, Terebralia bidentata, Crassostrea gryphoides, and Perna aquitanica; whereas deeper subtidal and fully marine conditions are documented by Turritella, Nassarius, Anadara, muricid gastropods, or venerids. Foraminiferal assemblages are dominated by benthic foraminifera and document brackish to shallow marine paleoenvironments. Most frequent genera are Ammonia, Aubignyna and elphidiids. Quiet water assemblages are indicated by higher portions of Caucasina and Nonion. The found assemblages enable us to trace sea level changes within the sections. They correspond largely to those described earlier by Rögl (1998). A complete measurement by hand-held gammalog spectral analysis detected throughout the succession prominent, highly significant periodicities with stratigraphic distance ranging from 12 m to 25 m, which have been interpreted as 21-kyr-precession signal. This indication for astronomical forcing allows further discussion of a reliable age-model for this section of the Korneuburg Basin

Casting new light on the chronology of the loess/paleosol sequences in Lower Austria

Der vorliegende Artikel gibt einen Überblick über neu datierte Abschnitte in bekannten Löss/Paläoboden-Sequenzen Niederösterreichs. Die Ergebnisse der Datierungen im Profil Joching deuten darauf hin, dass es im letzten Hochglazial zur Lösssedimentation kam. Die meisten erfassten Alter sind jedoch älter als das letzte Hochglazial, was auf Erosionsprozesse hindeutet, die zur Abtragung der jüngeren Lösse geführt hat. In dem Abschnitt zwischen ~28 ka and ~35 ka wurden überwiegend Tundragleye gebildet. Eine intensivere interstadiale Bodenbildung ist nicht nachzuweisen. Dieses Ergebnis kann auch für die stratigraphische Einstufung von ‚Stillfried B‘ (sensu Fink) von Bedeutung sein. Der folgende chronologische Abschnitt liegt zwischen ~35 ka and ~57 ka in Lösssedimenten mit eingeschalteten Tundragleyen. Auch dieser Abschnitt ist durch Umlagerungsprozesse charakterisiert. Im Zeitraum von ~57 ka bis ~106 ka befindet sich eine markante Zeitlücke, die vermutlich auf langandauernde und intensive Erosionsprozesse im Untersuchungsgebiet zurückzuführen ist. Die älteste Datierung in den Sedimenten des letzten Glazials mit 106 ± 12 ka befindet sich in Paudorf direkt über dem ‚Stillfried A‘- Komplex (Paudorfer Bodenbildung). Direkt unter diesem Pedokomplex, bzw. vergleichbaren Pedokomplexen treten in Lössablagerungen Alter von 124 ± 2 5 ka (Göttweig-Aigen), 159 ± 20 ka (Paudorf 1), and 170 ± 16 ka (Joching) auf. Darüber hinausgehende Alter konnten in Stratzing, Paudorf 2, Göttweig-Furth und Langenlois nachgewiesen werden

Coastal sandy spit deposits (Lower Burdigalian/Eggenburgian) in the Alpine-Carpathian Foredeep of Lower Austria

In the type-area of the Eggenburgian regional stage (Lower Burdigalian) sands with large-scale clinoforms were studied north-west of Eggenburg (Lower Austria). Stratigraphic and facies architecture, palaeocurrent pattern and inferred palaeogeographic setting show that these sands are deposits of W-E trending and SW to SSE prograding coastal spit systems, attached to crystalline shoals or islets in the shallow marine Eggenburg Bay. The spits were dominantly formed by shoal parallel accretion above fair-weather wave base due to longshore transport. The 4-5 m thick clinoforms with bottomset, foreset and topset structures contain up to 3.6 m thick, steeply inclined foresets, dominated by sediment gravity-flow deposition. Relatively stable depositional conditions, characterized by strong unidirectional currents, high sand supply and sufficient accommodation space are assumed for their formation. However, internal reactivation surfaces indicate variations in current activity, orientation and velocity. The deposits of spit systems are interpreted as part of a transgressive systems tract. The provenance analysis reveals the local Moravian and Moldanubian crystalline rocks as principal source. The spit sands of the Burgschleinitz Formation show the highest mineralogical maturity within the studied Lower Miocene succession. Intense reworking and redeposition of material from older deposits is evident. Due to the ongoing transgression deposits of the following Gauderndorf Formation and Zogelsdorf Formation exhibit a larger catchment area with input of high amounts of fresh weathered material

High-energy, microtidal nearshore deposits and their provenance (Lower Miocene, Burdigalian/Eggenburgian, Alpine-Carpathian Foredeep, Lower Austria)

During the Early Miocene (Early Burdigalian/Eggenburgian) marine transgression at the southeastern margin of the Bohemian Massif, gradual flooding occurred along a rocky coast on granitic bedrock of the Thaya Batholith under high-energy, wave-dominated, microtidal and mixed fair-weather and storm conditions. Deposits of the Burgschleinitz Formation overlie a basal unconformity above a subaerial weathered basement surface (transgressive erosional surface) and are interpreted as a transgressive systems tract. The deposits can be divided into four facies associations/depositional environments, i.e., upper-shoreface, foreshore, gravelly beach and backshore/lagoon. Two stages of transgression and successive overtopping of the basement, with different coastal physiographies, were documented. During the initial stage of transgression a barrier island system developed with relatively fine-grained deposits, reflecting the flooding of the distant parts of the Thaya Batholith with a relative flat basement morphology. The subsequent continuation of the transgression led to the flooding of the more proximal parts of the Thaya Batholith with a steeper relief and formation of a rocky shoreline with deposition of gravelly sedi- ments along palaeo-sea cliffs or wave-cut platforms. While gravel clasts of the deposits investigated originate directly from the underlying granites of the Thaya Batholith, provenance studies show that metamorphic rocks of the Moravian Superunit in the hinterland were the main source of sands. This distant source material was probably delivered mainly by small creeks and alluvial fans to the nearshore. Significant differences in heavy mineral composition of the same formation in the wider vi cinity indicate primarily local sources and rapid deposition with subordinate longshore transport, which may reflect a complex coastal palaeogeography. The Lower Miocene deposits of the Burgschleinitz Formation investigated are a rare example of ancient rocky shore deposits, which generally have low preservation potential in the geological record

Wachau World Heritage Site: A Diverse Riverine Landscape

The Wachau is a famous and picturesque riverine landscape along the Danube River in Lower Austria. It is a valley incised into the crystalline rocks of the Bohemian Massif. Middle Miocene (Badenian) sediments in the eastern part between Krems and Spitz indicate a pre-existent fjord-like bay of the Badenian Sea. Fluvial sediments in valleys north of the recent course of the Danube show a different, more northerly course of the Palaeo-Danube in the late Miocene. In the late Pliocene and Pleistocene, the Danube deeply incised into the southeastern margin of the Bohemian Massif along its recent course, presumably triggered by uplift caused by the northward moving Alpine units. Due to the influence of a warm Pannonian climate, the Wachau is suited for wine and apricot production. Since the Middle Ages terraces with simple rock walls, which are now a characteristic feature of the valley, have been constructed for easier cultivation. The Wachau has been inhabited since Palaeolithic times. Several important artefacts like sculptures of women found in Stratzing and Willendorf document the early human habitation that led to a continuous development until today. Along the valley historical buildings from Roman times, the Middle Ages, Renaissance and Baroque can be found. In 2000, the Wachau became a UNESCO World Heritage Site to protect the unique combination of cultural and natural sites. The World Heritage Trail connects the 13 municipalities of the Cultural Landscape Wachau and encompasses 20 ruins and castles, monasteries and the Wachau wine region. Natural hazards threatening the World Heritage Site are mainly floods and rockfalls

Transgressive rocky coasts in the geological record : Insights from Miocene granitic rocky shorelines and modern examples

Funding Information: We gratefully acknowledge the Norwegian Research Council (grant agreement 295208 ) and the companies Equinor, Lundin, Spirit Energy and Aker BP for sponsoring the Suprabasins project where this research is englobed. We would also like to thank the Hengl Company for allowing the fieldwork in the Limberg Quarry. Thanks to the editor-in-chief Dr. Catherine Chagué and two anonymous reviewers for their useful comments which have improved the content of the manuscript.Peer reviewedPublisher PD