Palaeogene and Neogene
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Palaeogene and Neogene MICHAEL W RASSER, MATHIAS HARZHAUSER (co-ordinators), OLGA Y. ANISTRATENKO, VITALIY V. ANISTRATENKO, DAVIDE BASSI, MIRKO BELAK, JEAN-PIERRE BERGER, GIANLUCA BIANCHINI, SAFET CICIC, VLASTA COSOVIC, NELA DOLA.KOVA., KATICA DROBNE, SORIN FILIPESCU, KARL GÜRS, SA.RKA HLADILOVA., HAZIM HRVATOVIC, BOGOMIR JELEN, _ JACEK ROBERT KASINSKI, MICHAL KOVA.C, POLONA KRALJ, TIHOMIR MARJANAC, EMÖ MA.RTON, PAOLO MIETTO, ALAN MORO, ANDRA.S NAGYMAROSY, JAMES H. NEBELSICK, SLAVOMIR NEHYBA, BOJAN OGORELEC, NESTOR OSZCZYPKO, DAVOR PAVELIC,, RAJKO PAVLOVEC, JERNEJ PAVSIC, PAVLA PETROVA, MARCIN PIWOCKI, MARIJAN POLJAK, NEVIO PUGLIESE, REJHANA REDZEPOVIC, HELENA RIFELJ, REINHARD ROETZEL, DRAGOMIR SKABERNE, VUBOMIR SLIVA, GERDA STANDKE, GIORGIO TUNIS, DIONYZ VASS, MICHAEL WAGREICH & FRANK WESSELINGH Over the last 65 Ma, our world assumed its modem shape. This Miocene to Plioeene sueeessor Lake Pannon. At its maximum timespan is divided into the Palaeogene Period, lasting from 65 extent, the Paratethys extended from the Rhöne Basin in Franee to 23 Ma and the Neogene, which extends up to the present day towards Inner Asia. Subsequently, it was partitioned into a (see Gradstein & Ogg (2004) and Gregory et al. (2005) for smaller western part eonsisting of the Western and the Central diseussion about the Quaternary). Paratethys and the larger Eastern Paratethys. The Western Throughout the Cenozoie Era, Afriea was moving towards Paratethys eomprises the Rhöne Basin and the Alpine Foreland Eurasia in a northward direetion and with a eountercloekwise Basin of Switzerland, Bavaria and Austria. The Central Para- rotation. Numerous mieroplates in the Mediterranean area were tethys extends from the Vienna Basin in the west to the eompressed, gradually fusing, and Eurasiaunderwent a shift from Carpathian Foreland in the east where it abuts the area of the a marine arehipelago to eontinental environments, related to the Eastem Paratethys. Eurasian eeosystems and landseapes were rising Alpine mountain ehains (Figs 17.1 & 17.2). Around the impaeted by a eomplex pattern of ehanging seaways and land Eoeene-Oligoeene boundary, Afriea's movement and subduetion bridges between the Paratethys, the North Sea and the Mediterra- beneath the European plate led to the final disintegration of the nean as well as the western Indo-Paeifie (e.g. Rögl 1998; Popov aneient Tethys Oeean. The Indo-Paeifie Oeean eame into ex- et al. 2004). This geodynamieally eontrolled biogeographie istenee in the east while various reliet marine basins remained in differentiation neeessitates the establishment of different ehron- the west. In addition to the emerging early Mediterranean Sea, ostratigraphie/geoehronologic seales. another reliet of the closure of the Tethys was the vast Eurasian The geodynamie ehanges in landscapes and environments were Paratethys Sea. further amplified by drastie climate ehanges during the Cenozoie. The Oligoeene and Mioeene deposits of Central Europe are The warm Cretaeeous elimate eontinued into the early Palaeo- largely related to the North Sea in the north, the Mediterranean gene with a distinet optimum near the Palaeoeene-Eoeene Sea in the south and the intermediate Paratethys Sea and its late boundary (Palaeoeene-Eoeene Thermal Maximum) and the 1032 PALAEOGENE AND NEOGENE 1033 ,'~'~.-._."- included a single result from stable Central Europe, or more recentty by Besse & Courtitlot (2002, 2003) who used five. (all representing the 16.5-34 Ma time interval). Thus, the Cenozoie apparent polar wander eurve (APWC), which serves to represent .•.. the displacements of stable Europe with respect to the present- ; day north and its shift in latitude, is a synthetic one computed by using palaeomagnetie data from all eontinents and transferred to stable Europe through a plate tectonic reconstruction model (e.g. Besse & Courtitlot 2002). Palaeomagnetie directions eomputed from the synthetic APWC suggest that stable Europe travelIed a few hundred kilometres northward during the Cenozoic, but did not change its orientation (within the limit of the resolution of palaeomagnetic observations, whieh in this case is c. ::i:5°).This implies that the expeeted stable European declinations are more or less aligned with the present meridians. The actually measured declinations at several points in stable Europe (e.g. France, Germany, Poland, Czech Republic; Global Palaeomagnetic Database 2005) deviate more from the present meridian than the coeval deelination computed rrom the synthetic APWC. Nonetheless, these devia- tions cannot be interpreted in terms of tectonics, since the Fig.17.2. Maiß physiographie and geological units ofCentral Europe. studied rocks, without exeeption, are igneous rocks, where Grey line marks the horder between the European Plale and the Alpine- securar variation of the Earth's magnetic field and poor control Late Eocene (Priabonian)35 Ma Carpathian orogenie system. Abbreviations correspond to official country on loeal tectonics can cause bias from the direction of the code plates. geomagnetic field. The stable European pattern of Cenozoic declinations breaks 500 km Transition indieated by the eooling of surfaee waters and the down as soon as we enter the North Alpine Foreland Basin at the expansion of the East Antarctic ieesheet (Shevenell et al. 2004). southern margin of stable Europe and south of this. The pattern A final trend reversal during the Early Pliocene is reflected by a here suggests large-scale movements during the Cenozoie Era, gentle warming until 3.2 Ma (Zachos et al. 2001) when the onset aceompanied by counterclockwise (CCW) rotations of variable of permanent Arctie glaciation heralded the Pleistoeene iee ages angles and timings; observations for dominant clockwise rota- (see Litt et al. 2008). tions are known only from the Apuseni Mountains (Romania) o The Cenozoie history of Central Europe is ehronieled in a and from the area between the Periadriatie and Sava faults. dense pattern of Palaeogene and Neogene basins. In addition to Sedi~ents Iying directly on the stable European margin exhibit the more stable North Sea Basin, the majority of these basins moderate CCW rotation (Scholger & Stingl 2004; Mi\rton et al. were strongly influenced by the Alpine eompressive tectonics 2003a). The mean angle of rotation is the same in every segment which caused a general uplift of Europe during the Cenozoic (Fig. 17.3), which is remarkable, since the age of the studied (see Froitzheim et al. 2008; Reicherter et al. 2008). The marginal sediments varies between 20 and 7 Ma. The termination of the position of the seas eovering the area and the eonsiderable rotations is not eonstrained in any of the segments. Therefore, synsedimentary geodynamie eontrol resulted in ineomplete strati- there are alternative solutions to explain these observations. One graphie sequences with frequent uneonformities, erosional sur- is that thc rotations were simultaneous between longitudes of faces and depositional gaps. 12°E and 23°E. In this case, the Bohemian Massif (which is This chapter deals with the Paleogene and Neogene ("Ter- considered to be part of stable Europe) must have been involved tiary") geological development of Central Europe and its in rotation. The other possibility is that the rotations are not adjaeent areas. It is struetured aeeording to the maiIl..geological eoeval and the sediments were detaehed from the stable regions relevant for the Cenozoie: (1) The European Plate; European basement. In either ease, the observations would ""i"i"i-~~I~ilerr~:n$~~m",,>,,",,~.," (2) the Alps and Alpine Foredeep; (3) the Carpathians, their require dramatic modifieation of existing tectonie models. foredeep and the Pannonian Basins System; and (4) the Southern As we move into thc mobile part of Europe, the palaeo- MiddleMiocene(Langhian) 15 Ma Latesl Miocene(Messinian) 6 Ma Alps and Dinarides. Eaeh subchapter is arranged from west to magnetie picture beeomes fairly eomplicated. During the Palaeo- east, and north to south. gene, there is no palaeomagnetic evidence for mobility, apart from a general northward travel for all tectonic units (Märton Land I;ÜHtbl Deep shelf f1~~1Anhydrite, gypsum 200 I). Rotations begin in the Miocene. Some of these can be D Palaeomagnelism and palaeogeography (KM.) related to tectonie escape from thc East Alpine realm, others to Mountain range Deep shelfal depression, Freshwater lake, I?'I 11II contlnental slope and ~ marshes Central Europe is eomposed of two tectonically contrasting subduetion pull in the Carpathians and the rest to the motion of Shallow shelf basin bottom regions: a northem Variscian region and a southem Alpine region the Adriatic micropiate (Adria). ~ (Figs 17.2 & 17.3). The former is called stable Europe in the Notable cases with rotations related to escape tectonics are palaeomagnetic literature, sinee the generally accepted view is known rrom the Eastem Alps and from the Periadrialic-Sava Fig. 1'.". Palaeogene- Neogene palaeogeography of Cenlral Europe (after Popov el al. 2004). that Europe, north of the Alpine rront, behaved as a rigid plate fault system (Fig. 17.3B, areas 10 and 11). In the first case, e. during the Cenozoie Era. However, the number of palaeomag- 30° of the CCW rotation observed in the sediments of the netic results supporting this view is surprisingly few and most of Miocene intramontane basins (Fig. 17.3B, area 10) are related to Early Eocene (Early Eocene Climate Optimum). A gradual 2003). A renewed warming trend that began during the Late them were acquired hefore 1980.