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The Early Jurassic full-marine sediments in NW Switzerland accumulated in the slowly subsiding area between the southwestern part of the Swabian Basin and the eastern Paris Basin. These deposits are dominated by fine-grained siliciclastics, but calcarenitic and phosphorite-rich strata are intercalated. Unlike in the adjacent regions of SW Germany and E France, they are arranged in a quite complex stratigraphic architecture characterised by rather abrupt facies changes, erosive truncations and gaps. Despite many common features in NW Switzerland, the sediments are considerably different with deposits of a similar age in SW Germany and E France that the definition of regional lithostratigraphic units is justified constituting the “Staffelegg Formation”. The Staffelegg Formation comprises 11 members and 9 beds. Several of these beds represent distinct correlation horizons. Some of them correspond to strata or erosional unconformities encountered in the Swabian realm, some of them can be correlated with strata in the Paris Basin. The thickness of the Early Jurassic strata varies between 25 and 70 m. In the eastern and central parts of NW Switzerland, sediments Sinemurian in age constitute about 90% of the thickness. To the West, however, in the Mont Terri area, Pliensbachian and Toarcian deposits form 70% of the thickness. The accommodation space of the Early Jurassic strata was controlled mainly by eustatic sea-level changes. While eustatic sea-level rise was low, isopach maps having a chronostratigraphic resolution of one sub-stage provide clear evidence of differential subsidence as pre-existing faults in the basement that formed during the late Palaeozoic became reactivated. Orientation of relative thickness anomalies follow the fault trends either those of the Rhenish Lineament or those of the North Swiss Permocarboniferous Trough. Isopach anomalies are superimposed on a general trend of decreasing thickness to the South. Their small areal extension suggests that strike-slip movements occurred locally with a mosaic of basement blocks. Reactivation of faults in the basement during the Early Jurassic is also evidenced by temporally enhanced hydrothermal activity as documented by chronometric age of veins and mineral alterations.

The Serbo-Macedonian Massif (SMM) is a composite crystalline belt within the Eastern European Alpine orogen, outcropping from the Aegean Sea in the south, to the Pannonian basin in the north. Farther north, it is correlated with the Supragetic nappe sequences of the South Carpathians. The central part of the massif, located in southeastern Serbia, southwestern Bulgaria and eastern Macedonia, consists of the medium- to high-grade metamorphic Lower Complex, and the low-grade metamorphic Vlasina Unit. Due to sparsity of detailed structural studies, geo- and thermochronological constraints, the geodynamic history of this area was considered enigmatic. In this study, U-Pb LA-ICP-MS analyses of zircons, geochemical analyses of major and trace elements of whole-rock samples, outcrop- and micro-scale investigation of ductile structures as well as 40Ar/39Ar and fission-track thermochronology were applied in order to define the provenance and tectonic evolution of the central SMM. The new results of U–Pb LA-ICP-MS analyses, coupled with Hf isotopic analyses of magmatic and detrital zircons, and major and trace element concentrations in whole-rock samples suggest that the central SMM and the basement of the adjacent units (i.e. Eastern Veles series and Struma Unit) originated in the central parts of the northern margin of Gondwana. These data provided a basis for a revised tectonic model of the evolution of the SMM from the late Ediacaran to the Early Triassic. The earliest magmatism in the Lower Complex, Vlasina Unit and the basement of Struma Unit is related to the activity along the late Cadomian magmatic arc (562-522 Ma). A subsequent stage of early Palaeozoic igneous activity is associated with (i) the reactivation of subduction below the Lower Complex and the Eastern Veles series during the Early Ordovician (490-478 Ma), (ii) emplacement of mafic dykes in the Lower Complex due to aborted rifting in the Middle Ordovician (472-456 Ma), and (iii) felsic within-plate magmatism in the early Silurian (439±2 Ma). The third magmatic stage is represented by Carboniferous late- to post-collisional granites (328-304 Ma). These granites intruded the gneisses of the Lower Complex, in which the youngest deformed igneous rocks are of early Silurian age, thus constraining the high-strain deformation and peak metamorphism to the Variscan orogeny. The fourth, Permian-Triassic (255-253 Ma) stage is late- to post-collisional and it is documented by within-plate felsic magmatism, related to the opening of the Mesozoic Tethys. Three major stages of ductile deformation were revealed based on the investigation of outcrop- and micro-scale ductile structures in the central SMM. The earliest stage of deformation D1 is related to isoclinal folding, commonly preserved as quartz-feldspar rootless fold hinges up to decimetre-scale. The second deformational stage D2 is associated with general southeastward tectonic transport and refolding of older structures into recumbent metre- to kilometre-scale tight to isoclinal folds. The deformational stages D1 and D2 could not be temporally separated, and probably occurred in close sequence. The age of these two ductile deformational stages was constrained to the Variscan orogeny based on indirect geological evidence (i.e. ca. 408-ca. 328 Ma). During this time the SMM was involved in a transpressional amalgamation of the western and eastern parts of the Galatian super-terrane and subsequent collision with Laurussia. Outcrop-scale evidence of the final stage of ductile deformation D3 is limited to the spaced and crenulation cleavage, which are probably related to the large-scale folding reported by earlier studies. Results of the 40Ar/39Ar thermochronology revealed three major stages of cooling in the central SMM from the early Carboniferous until the Early Jurassic. Cooling below greenschist facies conditions in the western part of the Vlasina Unit took place in a post-orogenic setting (extensional or transtensional) in the early Permian (ca. 284 Ma). The age of activity along the top-to-the-west shear zone formed within the orthogneiss in the Božica area of the Vlasina Unit was constrained to the Middle Triassic (ca. 246 Ma). This age coincides with widespread extension and magmatism related to the opening of the Mesozoic Tethys. The greenschist facies retrogression in the Lower Complex probably occurred in the Early Jurassic (ca. 195 Ma) and is probably related to thermal processes in the overriding plate above the subducting slab of the Mesozoic Tethys Ocean. Fission-track analyses on apatites and zircons revealed the existence of three major cooling stages from the late Early Cretaceous to the Oligocene. The first stage represents rapid cooling through zircon and apatite closure temperatures (300–60 °C) during the late Early to early Late Cretaceous (ca. 110–ca. 90 Ma). It is related to a post-orogenic extension following the regional nappe-stacking event in the Early Cretaceous. Middle to late Eocene (ca. 48–ca. 39 Ma) cooling is related to the formation of the Crnook-Osogovo-Lisets extensional dome and its exhumation along low-angle normal faults. The third event is related to the regional cooling following the late Eocene magmatic pulse. During this pulse the area surrounding the Surdulica granodiorite (36±1 Ma) and the slightly younger volcanic bodies (ca. 35 Ma) reached temperatures higher than the apatite closure temperature (110±10 °C) but lower than ca. 250 °C. The geochemistry of the igneous rocks reveals a late- to post-orogenic tectonic setting during magma generation.

The definition of planktonic foraminifera species remains a major challenge, despite their central place in biostratigraphy and paleoceanography. During the last decade, combined outcomes of molecular and morphometric studies have brought to the light challenging aspects of their classification: within the formerly and traditionally defined morpho-species exists a considerable degree of genotypic variation that defines biogeographically and ecologically distinct sibling "cryptic" species. The recognition of sibling species requires techniques, which are based on other properties than the sole shell morphology. The present work investigates the morphological variability in planktonic foraminifera of the sub-genus Menardella, a subset within the genus Globorotalia, in a time slice at 3.2Ma (Mid-Pliocene). This time was selected because it includes a major diversification of menardellids, during which 6 homeomorphic species evolved, leading to an intricate taxonomy. Here, a new population-based taxonomical approach is proposed, which relies on the combination of size frequency distributions (SFDs), geometric morphometry of the shells and sequential ontogenetic reconstructions of populations. A total of 7700 specimens collected from 19 localities in the tropical Atlantic, Pacific and Indian Oceans were investigated in great detail. The collection of morphometric data was achieved with the help of an automated device, the robot AMOR. The analysis of Mid-Pliocene menardellid SFDs allowed the identification of 6 different sedimentary populations, which on the basis of morphometric and other properties - allowed the recognition of 8 distinct morphotypes.These morphotypes are differentiated by their size distribution, the shape of their test (given by the ratio of axial diameter (dY)/spiral height (dX)), their wall structure and reflectivity and their number of chambers in the final whorl. The relative abundance of these morphotypes permits the establishment of 5 distinct menardellid provinces at 3.2 Ma: morphotypes MA and MB are cosmopolitans, whereas the morphotypes MC3, SH1 and SH2 are restricted to the Atlantic Ocean, and the morphotype ME to the Pacific Warm Pool. These morphotypes are compared with the formally established menardellid morpho-species. Both morphotypes MA and ME are interpreted as Globorotalia menardii. SFDs of these forms suggest the occurrence of two separated populations with distinct biogeographic ranges. Size is the most important parameter to distinguish these two morphotypes. Specific growth patterns derived from ontogenetic studies confirm that small specimens (

Fission-Track (FT) analysis of the Palaeozoic crystalline bedrock in the area of the southern Upper Rhine Graben (URG) showed complex and rapid changing upper crustal thermal conditions during the Mesozoic and the Cenozoic (Timar-Geng et al. 2004, 2006a). While an Eo-Oligocene thermal pulse accompanying the rifting of the URG is well documented by apatite FT modelling results (Timar-Geng et al. 2006a,b), the Jurassic hydrothermal period leading to a broad scatter of zircon FT data (Timar-Geng et al. 2004) are only weakly constrained. Additionally, due to a large sedimentary hiatus between the Upper Jurassic and the Late Eocene the pre-rift evolution remains still unclear. Knowledge about the thermal evolution of the area is essential for development of crustal scale models, which evaluate the rift-evolution. This study aims to clarify the timing of the Jurassic thermal pulse(s) and its potential to heat the Mesozoic sediments, which covers the Palaeozoic basement. Especially, the temperatures and geothermal-gradients that were reached are of mayor interest. During a hydrothermal period is convective heat transport the important mechanism, which influences the reached temperatures in the upper crust. Therefore, addresses a localised detail study at the URG main border fault the potential of fault-bounded thermal anomalies caused by ascending hot fluids to heat the surrounding rocks. The FT method, which is the base method used here, is a low-temperature thermochronological method widely used to quantify the thermal history of igneous, metamorphic and clastic sedimentary rocks. In particular, the FT analyses of detrital samples provide the advantage to discriminate between a pre-depositional thermal history of the provenance regions and a post-depositional basin related thermal history (e.g. Brandon 1998, Carter 1999, Bernet & Garver 2005, Armstrong 2005). The FT analyses oft the Permian and Mesozoic sediment column in the URG area, this study, compared with previous FT studies from the Black Forest and the Vosges (Michalski 1988, Wyss 2000, Timar-Geng et al. 2004, 2006a, b) led to a complete overview of the FT age signatures of URG pre-rift units. This is a requirement for the interpretation of Cenozoic detrital syn-rift deposits of the region by the FT method. New FT analyses on Cenozoic samples from the southern URG area led to basal insights in the syn-rift river drainage patterns.

Basin evolution in the Upper Rhine Graben (URG) was studied according to palecology, sedimentology, cross-section balancing and numerical modelling, with focus on the genesis of the Palaeogene series of the southern URG. Middle Eocene to Early Oligocene deposits accumulated under restricted conditions during an under filled basin stage. Sedimentation was controlled by differential tectonic subsidence and re-sedimentation of graben shoulder derived clastics within the graben and involved various depositional settings. Evaporites and marls were deposited in the depo-centre and a lacustrine to brackish facies developed in the marginal parts of the basin, while alluvial fans formed along the border faults. During Middle to Late Oligocene the URG was affected by supra-regional subsidence and connected to the overfilled North Alpine Foreland Basin, as reflected by a major marine transgression. The rift basin was converted into an over-filled open depositional system. Palecology of Early Oligocene laminites suggest marine influenced to isolated lake settings that experienced rapid fluctuations in salinity and lake level. Next to fluctuating Palaeo humidity the depositional dynamics were controlled by the elevated rift shoulders forming a barrier against external sediment/ water supply. Syn-rift subsidence was first order controlled by the width of the graben compartments and can be explained with extensional strain partitioning. Cross-section balancing shows that that the extension among the different rift compartments is almost the same and amounts to about 5 km. Consequently high extensional strain led to depo-centre formation in the narrow rift compartments, while relative low strain and subsidence occurred in the broad rift segments. Rifting durated from the Middle Eocene to the Early Miocene, renewed extension occurred during the Pliopleistocene. It occurred at constant but very low strain rates (1.7*10-16s-1) and involved brittle crustal deformation on a high viscous mantle. The necking level in the URG is located near the Moho. Under this circumstanced crustal extension is entirely compensated by rift basin formation. This will lead to strong static unloading equating the load of the replaced crust (Basin volume * crustal density). Flexural Isostasy modelling shows the Recent pattern of shoulder uplift can be explained with long term changes in crustal static loading due to URG rifting and Alpine Orogeny and an elastic plate thickness of 15 km, however the real observed rock uplift is higher than the modelled one. Eocene to Early Oligocene Rifting is likely to have occurred on a wide Alpine subduction related flexural forebulge. Regional subsidence during the middle Oligocene in the URG area might be explained with relaxation of this forebulge due to mechanical slab failure occurring at the transition from syn-post collisional Alpine orogeny stage. Renewed uplift that finalised Palaeogene sedimentary deposition and rifting however corresponds to a change in stress field from extension to compression and caused Neogene rise of the Vosges Black Forest Arc.

Pleistocene fluvial gravel terraces appear to be useful to decipher neotectonic movements. To achieve this, however, chronologic and sedimentologic data on the terraces are required. Thus, this thesis represents a multidisciplinary approach. After presenting methodological aspects of U/Th (Uranium-series disequilibrium) dating, compared to OSL (Optically Stimulated Luminescence), the ages obtained are used, together with sedimentological data, to constrain the formation processes and timing of the Late Pleistocene terraces in the Hochrhein area. Finally, the geometry of these terraces is interpreted in terms of neotectonics. Hitherto, dating coarse-grained sediment has proved often impossible due the lack of datable material, and developing new methods in this domain is thus of crucial importance. U/Th is a well established method, often used for speleothems and coral dating, and it is tested here on pedogenetic crusts growing within the Late Pleistocene gravels of the Hochrhein area. These results are compared to OSL ages from the same sampling sites. Our results show that this method has a development potential, but is highly dependant on a sufficient and stable Uranium content of the samples, which is partly controlled by bacterial activity. Comparisons with OSL ages highlight the fact that the event that is dated by mean of U/Th is the precipitation of the crust, not the deposition of the sediment. Sedimentological and morphological data show that the Late Pleistocene gravels (Lower Terrace) were deposited as a braided river, where flood events played a major shaping role. The gravels are arranged into terrace levels, where the highest level is an accumulation level, and the lower levels are erosion level with minor re-accumulation. The flood deposits are mostly conserved on top of the different terrace levels because the general incision regime prevented them from being reworked. OSL ages show that the main gravel accumulation occurred between 27 an 11 ka in the Hochrhein area, but minor re-accumulation occurred until historical times. The accumulation level was thus formed during the Younger Dryas, and the lower levels were formed from the Youger Dryas on, until historical times. These results are confirmed by radiocarbon ages from fossil trees and U/Th ages from speleothems. Terrace longitudinal profiles are used to assess neotectonic activity in the Hochrhein area. Four main groups of Pleistocene terrace exist in this area: the Earliest Pleistocene Higher Deckenschotter, the Early Pleistocene Lower Deckenschotter, the Middle-Late Pleistocene High Terrace and the Late Pleistocene Lower Terrace. The three older terrace groups do not show original surfaces anymore, so outcrop altitudes are used to build the longitudinal profi le. This profi le shows that the gradient of the terraces increases with their age, and each of the terrace groups show an increased gradient at the location where the profi le crosses the eastern main border fault (MBF) of the Upper Rhine Graben (URG). The terraces converge, cross and fi nally continue as basin fi lling. This suggests a relative uplift of the headwater area and extensional activity for the MBF during Pleistocene. The Lower Terrace features still well preserved surfaces and these are analysed with a high precision Digital Terrain Model (DTM). Using a high precision DTM highlights the complex arrangement of sublevels and the irregularities of the surfaces, which are mostly caused by sedimentary and erosive processes. NW of Basel in the URG, fi eld evidences indicate Late Pleistocene activity of NW-SE striking normal faults.

Planktonic foraminifera are marine, calcite secreting protists. They have a long history of study in both industry and academia. Individual species show distinct biogeographical distributions and ecological tolerances. Traditionally species concepts are based on the gross morphology of the foraminiferal test. The closer the morphology of two species, the closer they are related. This has resulted in a single species being named by several authors from differing global locations and also, in long lived species, differing time intervals. This work investigates morphological variation of Late Pleistocene – Holocene menardiform globorotalids, and links this morphological variation to different ecological and environmental conditions. To achieve this 70 global sample sites are investigated covering a range of differing environmental conditions, but within constrained time limits. Where possible samples dated as Holocene have been used, where absolute dating was unavailable samples from about the Emiliani huxleyi acme zone, giving an upper age is given of 65 – 70 thousand years. Analysis of morphological variation allowed identification ofintergrading morphoclines and a total of six distinct morphotypes (e.g. the menardi-form morphotypes α, β, χ and η and the two tumid form morphotypes ε and φ). The morphotypes are shown to have distinct though overlapping biogeographic distributions. In the bivariate morphospace of spiral height versus axial diameter the equation y = 2.07x –15 separates morphocline(G. menardii morphologies) from morphocline(G. tumida morphologies). Within morphoclinethe line with equation y = 3.2x –160 separates morphotypes α (G. menardii menardii) from morphotype β (G. menardii cultrata). Morphotype β is interpreted as G. menardii cultrata and is seen to dominate environments with mean annual sea surface temperatures over 25°C. Morphotype α is interpreted as G. menardii menardii and becomes more dominant as sea surface temperatures become cooler. In areas where both morphologies are present in a sample we interpreted the situations a vicariant trophic depth adoption. G. menardii cultrata lives at shallow depths, while G. menardii menardii occurs deeper within the water column. This interpretation is supported by stable isotope studies carried out on samples from the Gulf of Mexico and Caribbean region where the two morphologies show significantly different isotopic signals. G. menardii cultrata morphologically has a flattened smooth test with little secondary encrusting, while isotopically it has a shallow depth habitat and possible symbiotic relationship. G. menardii menardii morphometrically shows greater inflation and encrusting of the test and isotopically it shows a deeper and colder depth habitat. The presence of all ontogenetic stages within the two recognized morphological groups with distinct isotopic signatures, suggests that G. menardii may have two distinct subpopulations living at different depths within the Caribbean. Ultrastructural studies on adult forms of morphotypes α and β from the same size fractions taken from a single sample, show that differences are present even in juvenile growth stages. Prolocular size and rate of growth suggest that morphotype α has a r-selected (rapid growth, opportunistic) mode of life. While morphotype β is k-selected (longer living, symbiont bearing, specialist) mode of life. Morphotype η is interpreted as G. menardii gibberula this is the highest spired morphotype within the G. menardii group and is found only at the southerly extent of the sample set. Specimens have been identified in sample sites from the Western Pacific, which extends its known biogeographic range. It also has the highest spire of all the menardii forms and shows a correlation to the coldest sea surface temperatures. Morphotype χ is only found in the northern part of the Indian Ocean and is interpreted as G. menardii neoflexuosa. It has a distinct flexure of the final chamber, but with removal of the final “flexed” chamber, the morphotype falls within morphotype β morphospace, to which is shows similar textural structure. The cause of the flexing is not clear, but as it is found in increased numbers during the summer monsoon, it has been suggested that it is a response to lowered salinity and an increase in turbidity of the surface waters. Within morphocline 2 morphotype ε (G. tumida) is seen to intergrade the morphologically similar but texturally different morphotype φ (G. ungulata). The diminutive size and delicate structure of G. ungulata is suggestive of it being the shallow dwelling juvenile form with being G. tumida the deeper dwelling more robust adult form. However, isotopic studies show differing depth habitats for the two morphotypes, with the heavier encrusted G. tumida showing a constantly deeper signal than the smoother more delicate form of G. ungulata, when comparing size equivalent specimens from the same sample sites. The first occurrence of G. ungulata is unclear but is believed to occur during the late Pleistocene. Because of this the results are interpreted as indicating ecophenotypic variation within a species, rather than just ontogenetic variation, with morphotype φ representing the shallow dwelling morphology, and morphotype ε the deeper dwelling morphology. Secondary encrusting of all specimens used in this present study indicates that encrusting is a function of which the foraminifera lived an not an indication of its stage of ontogeny or gametogenesis.

Combining thermochronological methods with structural field data, this study aims to reconstruct the Tertiary burial and exhumation history of the northeastern part of the Tisza‐ Dacia block during its invasion in the Carpathian embayment and final soft collision with the European margin. Zircon fission track data additionally provide information about the last metamorphic overprint during the Cretaceous. Within the basement units of the northern Central East Carpathians (Bucovinian nappe stack) and the Preluca massif (Biharia unit) zircon fission tracks are largely reset during the last (Cretaceous) orogeny. Temperatures during this Alpine metamorphic overprint increase from external to internal within the northern East Carpathians from sub‐greenschist facies conditions to at least greenschist facies conditions. Greenschist facies conditions are also observed in the Preluca massif. The close neighbourhood of Coniacian to Campanian zircon FT cooling ages with Cenomanian sediments suggests Late Cretaceous tectonic exhumation in the northern East Carpathians. The most likely explanation for this tectonic exhumation is a ‐ so far undocumented ‐ Late Cretaceous extension related to orogenic collapse (Gosau type basins). The Tertiary evolution is characterised by the invasion of the previously amalgamated Tisza‐Dacia and ALCAPA blocks into the Carpathian embayment and Miocene soft collision of both these blocks with the European margin. The juxtaposition of the ALCAPA and Tisza‐Dacia blocks, with Tisza‐Dacia in a lower plate position, is announced by the onset of Oligocene turbiditic sedimentation. The Burdigalian SE‐directed over‐thrusting of the Pienides (non‐ metamorphic flysch units) is interpreted to express the final stages of this juxtaposition. Burial heating caused full annealing of fission tracks in apatite (i.e. >120°C) in the Central East Carpathian basement in the NE of the study area, while in the basement of the Preluca massif in the SW of the study area temperatures related to Paleogene to Early Miocene burial did not exceed 80°C. The post‐Burdigalian (post‐16 Ma) soft collision of Tisza‐Dacia with the European margin occurred in two stages expressed by predominantly sinistral strike‐slip deformation during constant NE‐SW shortening. During and following soft collision, combined uplift and erosion caused exhumation of the buried rocks along the European margin. Uplift reaches up to 9 km in the Rodna horst The first post‐Burdigalian transpressional stage (16‐12 Ma) is related to perpendicular convergence of Tisza‐Dacia with the NW‐SE striking European margin. Minor exhumation during this stage resulted in Middle Miocene apatite fission track cooling ages (15‐13 Ma) in the west of the study area. The transtensional stage (12–10 Ma) led to the formation of the Bogdan‐Dragos‐Voda fault system. Sinistral transtension allowed for the docking and fitting of Tisza‐Dacia with the NW‐ SE striking European margin. Oblique E‐W convergence led to strain partitioning with thrusting in the external thrust belt and internal strike‐slip deformation. Differential lateral movements are distributed and deformation is accommodated by E‐W striking sinistral strike slip faults and SW‐NE striking normal faults, which led to fragmentation into SW‐tilted blocks. Fragmentation and differential offset along the bounding faults resulted in the formation of triangular‐shaped graben and corresponding horst structures. Enhanced exhumation during transtensional activity led to advective heat transport and resulted in Middle to Late Miocene apatite fission track cooling ages (13‐7) in the east of the study area.

The Upper Rhine Graben (URG) is the most discernible part of the European Cenozoic rift system. Uplifted Variscan basement is exposed in the Black Forest and the Vosges and forms the flanks of the southern URG. The impact of the Jurassic hydrothermal activity on the interpretation of fission track (FT) data from the southern URG is elaborated by means of new zircon FT analysis on samples with known U/Pb crystallisation ages. Zircon FT central ages range from 162 Ma to 247 Ma. The analysed samples experienced substantial annealing prior to Cretaceous cooling that cannot be explained by burial alone. Instead, it is suggested that circulating hydrothermal fluids with temperatures in the order of 200-250 °C are responsible for the observed thermal anomaly, which is also evidenced by vein mineralizations. FT ages of 28 outcrop samples collected along two E-W trending transects from the Black Forest and Vosges vary from 136 Ma to 312 Ma (zircon samples) and from 20 Ma to 83 Ma (apatite samples). Broad and/or bimodal track lengths distributions indicate a complex thermal history, which was determined by inverse modelling of apatite FT parameters and tested against the observed dataset and independent geological constraints. Cooling below 120 °C in the Early Cretaceous to Palaeogene was followed by a discrete heating event during the late Eocene and subsequent cooling to surface temperature. The modelled time-temperature paths point to a total denudation of the flanks of the URG in the range of 1.0-1.7 km for a paleogeothermal gradient of 60 °C/km, and 1.3-2.2 km for a paleogeothermal gradient of 45 °C/km since the late Eocene. Zircon and apatite FT data from four boreholes, which penetrate the Mesozoic and pre-Mesozoic sediments and crystalline basement of northern Switzerland, are also presented. Inverse thermal modelling of the apatite FT parameters reveals the low-temperature thermal history of the crystalline basement of northern Switzerland. Moderate to rapid cooling of the samples through the apatite partial annealing zone (PAZ) at the end of the Mesozoic was followed by a distinct thermal event during the Eocene and subsequent slow cooling to present-day temperatures. The Eocene heating episode coincides with the initial rifting phases of the neighbouring URG and associated volcanic activity. Crustal-scale faults of the PermoCarboniferous Trough of northern Switzerland could have acted as major pathways for circulating hydrothermal fluids giving rise to the observed Eocene thermal event.

By integrating detailed structural and sedimentological field-work with paleomagnetic data, this thesis provides constraints for the reconstruction of the Late Tertiary tectonic history of the nner Carpathians in Northern Romania. Central for the understanding of the formation of the Carpathians is the emplacement history of crustal blocks into the so-called ‘Carpathian embayment’. This large-scale bight in the European continental margin is situated between the Bohemian and Moesian promontories. Roll - back of the (partly?) oceanic crust formerly occupying the Carpathian embayment, combined with lateral escape due to indentation in the Eastern Alps are thought to be the driving forces for this emplacement. The irregular shape of the European continental margin ultimately led to the formation of a highly bent orogen, the Carpathians. The study area is a key area for the understanding of the tectonic processes during this emplacement, since it is situated at a triple point where three of the major continental bocks (ALCAPA, Tisza and Dacia) meet. During the time interval covered by this study, the Tisza and Dacia blocks are considered firmly attached to each other, representing one single block. A large fault zone between the ALCAPA block and the Tisza-Dacia block, termed Mid-Hungarian fault zone, accommodated most of the complex deformation caused by their contemporaneous invasion into the Carpathian embayment. During emplacement corner effects at the Bohemian and Moesian promontories resulted in large differential rotations of the invading blocks. The juxtaposition of the Tisza-Dacia block and the ALCAPA block along the MidHungarian fault zone resulted in the formation of a flexural basin on the northern part of Tisza-Dacia. The filling of this basin started in Oligocene times, developing from flysch units into Burdigalian-age molasse-type deposits. The last moment of thrusting of ALCAPA related units onto Tisza-Dacia is reflected by the Early Burdigalian SE - directed emplacement of unmetamorphic flysch nappes (Pienides) onto the autochthonous cover of Tisza-Dacia. Back-arc type extension leading to the formation of the Pannonian basin is in the study area only weakly documented as SW-NE extension. Roughly perpendicular ‘soft collision’ of Tisza-Dacia with the European margin leads to transpressional deformation in the study area after 16 Ma. Due to migration of slab retreat, the convergence direction of Tisza-Dacia becomes more oblique, initiating a deformation stage characterized by transtension (NW – SE extension). The northern rim of Tisza-Dacia is ‘fitted’ to the European continental margin by E-W trending, sinistral strike slip faults coupled to SW – NE trending normal faults. This process leads to a weak (~20°-30°) counterclockwise rotation as well as accelerated uplift of the northern part of Tisza-Dacia. After 16 Ma deformation in the study area is located within the Tisza-Dacia block, but most likely connected to the Mid-Hungarian fault zone.

In the Ajoie-Region, seven in situ collected species of ammonites helped to establish a new biostratigraphical an dlithological frame for the platform sediments of the Reuchenette Formation, i.e. eighteen closely spaced sections have been spliced by means of lithological, sedimentological, microfacial data and index-fossils (ammonites). Three marker beds achieved the exact lithological correlations between the outcrops corroborated by the vertical faciese changes. Based on the biostratigraphical data five 3rd order sedimentary sequences could be asigned to the Late Oxfordian to Late Kimmeridgian time interval. The sequence boundaries lie within the Planula-, Platynota-, Divisum-, Acanthicum- and Eudoxus-Zone. The upper three 3rd order sequences correspond to the Boreal sequences Kim3 to Kim5 of Hardenbol et al. (1998). The deduced "large-scale" sea level trend matches those from other Euoprean regions (Spain, Russia). At platform scale, this time control and further outcrops south of the Ajoie-Region, in combination with mineralostratigraphical and lithological marker beds, allowed the correlation and dating of the thickest sections - including the type-section - of the Reuchenette Formation and thus serve to oimprove the previously estimated ages of their sequence boundaries (see above). The variability of stacking pattern and facies between the sections also reveals distinct changes in facies evolution occurring across Late Palaeozoic basement structures and suggest synsedimentary differential subsidence. These sturctures acted as important controlling factors for the distribution of the sediments of the Reuchenette Formation besides the sea level fluctuations. The interplay of sea level changes and synsedimentary differential subsidence is outlined by lateral thickness variations and conspicuous laterally changing depositional environments. A close examination of these changes also sheds much light on the nature of platform topography in the transition area between the Paris Basin and the Tethys. During the Planula- to Divisum-Zone time interval the study area was a flat platform with a more or less uniform facies distribution, which connected the above-mentioned realms. During the Divisum- to Acanthicum-Zone time interval this platform changed into a pronounced basin-and-swell morphology with specific depositional environments and "separated" the Paris Basin from the Tethys. Dinosaurs might have used this boundary to traverse between the Central Massif and the London-Brabant Massif during sea level lowstands.