Neogene of the Alpine-Carpathian Foreland Basin Oead - STC Project SK 09/2018 - at Excursion #1 19-21 October 2018 - Upper and Lower Austria
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Neogene of the Alpine-Carpathian Foreland Basin OeAD - STC Project SK 09/2018 - AT Excursion #1 19-21 October 2018 - Upper and Lower Austria Neogene of the Alpine-Carpathian Foreland Basin OeAD - STC Project SK 09/2018 - AT Excursion #1 19-21 October 2018 - Upper and Lower Austria Prepared by Oleg Mandic1, Mathias Harzhauser1, Christian Rupp2, Reinhard Roetzel3 and Matthias Kranner1 1 Natural History Museum Vienna, Burgring 7, 1010 Wien, Austria. 2 Geological Survey of Austria, Neulinggasse 38, 1030 Wien, Austria. 2018 Natural History Museum Vienna Schedule Light conditions: daylight 7:30 - 18:00 18.10. Thursday 1. Geboltskirchen - Meeting Point at Landgasthof Ledererwirt (18:00-20:00) #1st day - 19.10. Friday Bed & Breakfast - Landgasthof Ledererwirt, Feld 2, 4682 Geboltskirchen 1. Gravelpit Urhamer - Hausruck Fm. and Ampflwang Fm. (upper Miocene) - 48.116360 13.566042* 2. Eberschwang-Straß - brickyard - Ried Fm., stratotype (middle Ottnangian) - 48.116360 13.566042 3. Kalletsberg - Ampflwang Fm., stratotype (upper Miocene) - 48.068654 13.612187 4. Ottnang - Sandpit Fischer - Atzbach Fm. (lower Ottnangian) - 48.094442 13.663962 5. Ottnang Schanze - Ottnang Fm., stratotype, holostratotype (lower Ottnangian) - 48.101944, 13.667778 6. Prambachkirchen - Weinzierlbruck pit - Linz-Melk Fm. (Egerian); Plesching Fm. (="Phosphoritsand"; lower Ottnangian) - 48.322098 13.901664 7. Unterrudling - former brickyard Obermair - Linz-Melk Fm. and Eferding Fm. (stratotype) (lower Egerian) - 48.304686 13.995454 #2nd day - 20.10. Saturday Bed & Breakfast - Cleverhotel, Hotelstraße 2 / St. Pöltnerstraße 120, 3130 Herzogenburg 1. St. Pölten - Prater - Traisen Fm. (upper Ottnangian) - 48.215573 15.621387 2. Obernholz - Fels Fm. (lower Eggenburgian) - 48.510341 15.742254 3. Kirchenbruch - Burgschleinitz Fm., faciostratotype (upper Eggenburgian) - 48.604930 15.816054 4. Johannesbruch - Zogelsdorf Fm., stratotype (lower Ottnangian) - 48.620063 15.810652 5. Limberg - Quarry Hengl - Burgschleinitz Fm. and Zogelsdorf Fm. (lower Ottnangian) - 48.594906 15.854259 6. Limberg - Taubenberg diatomite pit - Limberg Mb. / Zellerndorf Fm. (upper Ottnangian) - 48.597867 15.871917 7. Straning - tuff and tuffite (Karpatian) / Zellerndorf Fm. (Ottnangian) - 48.619167 15.859500 #3rd day - 21.10. Sunday Bed & Breakfast - Gasthof Berger, Hauptplatz 15, 3712 Maissau 1. Mailberg - Buchberg - Mailberg Fm., stratotype (Badenian) - 48.671138 16.156577 2. Breitenwaida - Hollabrunn Fm. (Pannonian) - 48.528074 16.075519 3. Göllersdorf - Laa Fm. (Karpatian) - 48.501315 16.125175 4. Kleinebersdorf - Wohlmuth - Korneuburg Fm. (Karpatian) - 48.493991 16.399017 5. Stetten - "Fossilienwelt" - Korneuburg Fm. (Karpatian) - 48.367392 16.359197 * WGS84 Coordinates (N/E) ii iii Fig. 1-1 (previous side). Geographic position of the Excursion sites; A. with indicated tectonic and paleogeographic units and position of maps beneath; B. Upper Austrian sites (1st day); C. Lower Austrian sites (2nd and 3rd day) (Google Earth, downloaded on 18/10/2018). Fig. 1-2. Oligocene – Miocene geochronology, geomagnetic polarity chrons, biozonations of planktonic foraminifers and calcareous nannoplankton, sequence stratigraphy and sea level, and oxygen isotope stratigraphy partly recalibrated and correlated to regional chronostratigraphy of the Central Paratethys. The black dots on the right column indicate the stratigraphic position of the holostratotypes of the regional stages (modified after Piller et al., 2007, Stratigraphy 4/2-3, p. 153). iv OeAD - STC Project SK 09/2018 - AT Excursion #1 #1st day - 19 Oct 2018 (Friday) Tectonic unit: Molasse Unit, North Alpine Foredeep The Upper Austrian North Alpine Foreland Basin (Molasse Unit) The Molasse Unite is an asymmetrical foreland basin between the crystalline of the Bohemian Massif in the north and the Alpine bodies in the south. Their more or less flat-lying sediments overlay the older rocks (crystalline, autochthonous Mesozoic sediments) of the Eurasian Plate. After a long period of erosion during the Paleogene, marine sedimentation started again in the Late Eocene (Wagner, 1998). The separate evolution of the Molasse zone started in the earliest Oligocene with the expansion of distinct Paratethys faunal and floral elements (Steininger & Wessely, 2000). In Upper Austria, north of the active Alpine Orogeny, relatively deep and partly isolated basins were developed. In the Early Oligocene (Kiscellian) marine deep-water formations like the Schöneck Fm., the Dynow- Fm., the Eggerding Fm. and the Zupfing Fm. were deposited, overlain by the late Oligocene to early Miocene (Egerian) Puchkirchen Fm. with marls and coarse grained deep-water channel sediments (De Ruig & Hubbard, 2006). At the same time, neighboring the Puchkirchen Fm. to the north, the marly Eferding- and Ebelsberg Formations were deposited, partly interfingering with the shallow marine and sandy Linz-Melk Fm., which laps on the Bohemian Massif. In the Eggenburgian, during the deposition of the Hall Fm., the Molasse Basin deep-water sedimentation ended (Grunert et al., 2013). During the early and middle Ottnangian a wide range of neritic formations were deposited (Fig. 2-1). In addition, the character of sedimentation changed distinctly (Steininger & Wessely, 2000). During the Egerian, the Upper Austrian Molasse basin was rather a semi-enclosed sea, bordered by the Bohemian Massif in the north, the Lower Freshwater Molasse in the west and the rising Alpine nappes in the south, where a marine connection across the partly still submerged Alpine system to the Mediterranean basin was postulated by Wagner (1996). With the end of the Eggenburgian a seaway to the west was established connecting the Molasse Basin via the Rhone valley with the Mediterranean (Steininger & Wessely, 2000) and providing the establishment of a tidal dominated sedimentary regime. Sandy tidal channel sediments (Atzbach Fm., Mehrnbach Fm. etc.), interfingering with marly low energy sediments (Ottnang Fm., Ried Fm., etc.), characterize the early to middle Ottnangian Molasse (Fig. 2-1). In the late Ottnangian the Upper Austrian Molasse Basin was almost filled up with sediments, marine sedimentation ended and the shallow brackish water Oncophora beds were deposited. Subsequently exclusively freshwater sediments of Karpatian to Pannonian age, including several coal-bearing formations, are to be found in the Upper Austrian Molasse Basin. The most remarkable formations are the Kobernaußerwald Fm., the Ampflwang Fm. and the Hausruck Fm., which build up the elevations of Hausruck and Kobernaußerwald (Rupp et al., 2011). Quaternary sediments are widespread in Upper Austria but disregarded here. Source: Pervesler & Glowniak, 2015 1. Gravelpit Urhamer Topic: Hausruck Fm. Age: late Miocene The Gravelpit Urhamer is located north of Ampflwang, approximately 1000 meters west of the Urhamerberg. Here the rather thin Ampflwang Formation (Kohlentonserie) is overlain directly by the Hausruck Formation, which is dominated by grey to yellow – brown mid – to coarse gravels within a mid to coarse sand matrix. Occasionally the matrix shows carbonatic cementation (up to 45% carbonate) leading to conglomerated blocks covering large parts of the quarry. Due to alteration, 1 weathering and dissolution these blocks are imbedded in loos gravel (Mackenbach, 1984). Within the not well sorted Hausruckgravel some cross-bedded sand layers or lenses and seldom clay layers or clasts occur. The gravel facies is dominated by quartz and crystalline whereas the matrix shows high contents of Garnet, Epidote, Hornblende and some Staurolite (Aretin, 1988a). Fig. 2-1. Stratigraphical overview of the Molasse Zone of Upper Austria and Salzburg 2 The Hausruckgravel lies on the gravelly Kobernaußerwald Formation in the West and on the coal-bearing Ampflwang Formation in the East and is roughly striking from WSW to ENE, whereas the underlying Kobernaußerwaldgravel is striking from NNW to NNE (Mackenbach, 1984). Age determination of the Hausruckgravel was mostly conducted using vertebrate fossils. Since the 19th century mammal fossils of the genera Dorcatherium, Dicerorhinus, Hipparion and Tetralophodon were described from the area surrounding Haag which allowed a rough age determination to the Pannonian (Thenius, 1952). Currently in re-cultivation and not presentable, the gravelpit Schernham, positioned 7.6 km NNE of the present gravelpit Urhamer (Fig. 2-2), revealed layers bearing gastropods, fish, amphibians, serpents, lizards, turtles and birds, as well as other mammals like rabbits, rodents, horses and elephants. With this fauna a further restriction to the mammal zone MN10 and the mollusk zone G (upper Pannonian, ~9 Ma) was established. Besides from this locality Pseudocollimys steiningeri (Cricetidae, Rodentia, Mammalia) was introduced by Daxner-Höck (2004). Fig. 2-2. Photograph of the gravelpit Urhamer and sediment distribution of the Freshwater-Molasse including the Hausruck Fm. (Daxner-Höck, 2004). The Hausruckgravel represents fluviatile deposits with high currents, whereas limnic deposits are rather seldom and just represented with a few thin sand and clay layers. The allochthonous vertebrate fauna indicates a meandering river system lined with trees and woods with some clearings (interpretation due to larger mammals). Source: Extracted from Rupp et al. 2007 (modified) 2. Eberschwang-Straß - brickyard Topic: Ried Fm., stratotype Age: middle Ottnangian This section, from the eastern Alpine foredeep of northern Austria, displays up to 30 m of clayey silt belonging