Coalification, shale diagenesis and thermal modelling in the Alpine Foreland basin: the Western Molasse basin (Switzerland/France)

<p>Foreland basin sediments mirror the history of an orogeny. Deformation and geodynamic processes in low spatial extend (e.g. dozens of km) can be quantified using kinematic restoration. Processes happening deep underneath an orogen show a large spatial manifestation that is difficult to quantify in time and space. Marine units at surface outcrops show 900 m of net uplift since deposition in undeformed parts of the alpine foreland basin. Existing low-temperature thermochronology data from the Swiss part of the Molasse Basin show a thermal overprint that indicates exhumation of more than 1.5 km. We quantify the wavelength of deep seated processes of the Alpine orogen by generating and analyzing a holistic dataset of the entire alpine foreland basin. In addition to compiling existing data from the western part of the basin we have generated a new apatite (U-Th)/He and vitrinite reflectance data set from the central and eastern part of the basin. The new apatite (U-Th)/He ages in the German part of the basin show exhumation below or close to the detection limit (~1.5 km). Within the folded and thrusted Molasse, exhumation is localized along thrusts and the thermochronological data indicates thrusting between 10 to 20 Ma. Vitrinite reflectance data reveals a trend of exhumation increasing from East to West. Parts of the central German Molasse basin have been exhumed as well. Thus, on the large scale we can see longwave exhumation patterns in the western part of the basin that affect both the deformed and undeformed parts of the basin which cannot only be related to Jura thrusting.</p>

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Detailed Fluid Inclusion and Stable Isotope Analysis on Deep Carbonates from the North Alpine Foreland Basin to Constrain Paleofluid Evolution

Geofluids ◽

10.1155/2019/8980794 ◽

2019 ◽

Vol 2019 ◽

pp. 1-23 ◽

Cited By ~ 2

Author(s):

Elena Mraz ◽

Markus Wolfgramm ◽

Inga Moeck ◽

Kurosch Thuro

Keyword(s):

Fluid Inclusions ◽

Foreland Basin ◽

Upper Jurassic ◽

Molasse Basin ◽

Drill Cuttings ◽

The North ◽

North Alpine Foreland Basin ◽

Alpine Foreland ◽

Alpine Foreland Basin ◽

Reservoir Evolution

The recent interest on environmentally friendly energy resources has increased the economic interest on the Upper Jurassic carbonate rocks in the North Alpine Foreland Basin, which serves as a hydrogeothermal reservoir. An economic reservoir use by geothermal fluid extraction and injection requires a decent understanding of porosity–permeability evolution of the deep laying Upper Jurassic strata at depths greater than 2000 m. The analysis of paleofluids caught in cements of the rock mass helps to determine the postdepositional reservoir evolution and fluid migration. Therefore, the high- and low-permeability areas of the Upper Jurassic in the North Alpine Foreland Basin referred to as Molasse Basin were analyzed by means of encountered postdepositional cements to determine the reservoir evolution. The cements were sampled at different hydrocarbon and geothermal wells, as well as at outcrops in the Franconian and Swabian Alb. To determine the composition and temperature of the paleofluids, fluid inclusions and cements of the Upper Jurassic carbonate rocks were analyzed by microthermometry and stable isotope measurements. Since drill cuttings are a rather available sample material compared to drill cores, a new microthermometry measurement method was achieved for the around 1 mm drill cuttings. Salinity and formation temperature of paleofluids in fluid inclusions and isotope data are consistent with previous studies and reveal a 5-stage evolution: the main cementation phases are composed of (I) the early diagenesis in limestones (200-400 m, 40-50°C), (II) early diagenetic dolomitization, and (III) burial dolomitization (1-2 km, II: 40-90°C; III: 70-100°C; 40 g/L NaCl equiv.), and (IV) late burial calcification (IIIa: 110-140°C, IIIb: 140-200°C) linked to tectonic features in the Molasse Basin. In the outcrop samples, a subsequent (V) cementation phase was determined controlled by karstification. In the southwest, an increase in salinity of the fluid inclusions in vein calcites, above the salinity of the Jurassic seawater, highlights the influence of basin fluids (diagenetic, evaporitic). In the other eastern wells, vein calcites have precipitated from a low saline fluid of around 10-20 g/L NaCl equiv. The low salinity and the isotope values support the theory of a continuous influence of descending meteoric fluids. Consequently, the Upper Jurassic seawater has been diluted by a meteoric fluid to a low saline fluid (<1 g/L), especially in areas with high permeability. Here, we show how a better understanding of cementation trajectory at depth can help to generate a better understanding of geothermal usability in deep carbonate reservoirs.

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Miocene high elevation in the Central Alps

Solid Earth ◽

10.5194/se-12-2615-2021 ◽

2021 ◽

Vol 12 (11) ◽

pp. 2615-2631

Author(s):

Emilija Krsnik ◽

Katharina Methner ◽

Marion Campani ◽

Svetlana Botsyun ◽

Sebastian G. Mutz ◽

...

Keyword(s):

Sea Level ◽

Foreland Basin ◽

European Alps ◽

Molasse Basin ◽

Central Alps ◽

Pedogenic Carbonate ◽

Northern Alpine Foreland ◽

History Of ◽

Alpine Foreland ◽

Alpine Foreland Basin

Abstract. Reconstructing Oligocene–Miocene paleoelevation contributes to our understanding of the evolutionary history of the European Alps and sheds light on geodynamic and Earth surface processes involved in the development of Alpine topography. Despite being one of the most intensively explored mountain ranges worldwide, constraints on the elevation history of the European Alps remain scarce. Here we present stable and clumped isotope measurements to provide a new paleoelevation estimate for the mid-Miocene (∼14.5 Ma) European Central Alps. We apply stable isotope δ–δ paleoaltimetry to near-sea-level pedogenic carbonate oxygen isotope (δ18O) records from the Northern Alpine Foreland Basin (Swiss Molasse Basin) and high-Alpine phyllosilicate hydrogen isotope (δD) records from the Simplon Fault Zone (Swiss Alps). We further explore Miocene paleoclimate and paleoenvironmental conditions in the Swiss Molasse Basin through carbonate stable (δ18O, δ13C) and clumped (Δ47) isotope data from three foreland basin sections in different alluvial megafan settings (proximal, mid-fan, and distal). Combined pedogenic carbonate δ18O values and Δ47 temperatures (30±5 ∘C) yield a near-sea-level precipitation δ18Ow value of -5.8±1.2 ‰ and, in conjunction with the high-Alpine phyllosilicate δD value of -14.6±0.3 ‰, suggest that the region surrounding the Simplon Fault Zone attained surface elevations of >4000 m no later than the mid-Miocene. Our near-sea-level δ18Ow estimate is supported by paleoclimate (iGCM ECHAM5-wiso) modeled δ18O values, which vary between −4.2 ‰ and −7.6 ‰ for the Northern Alpine Foreland Basin.

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Miocene high elevation and high relief in the Central Alps

10.5194/se-2021-59 ◽

2021 ◽

Author(s):

Emilija Krsnik ◽

Katharina Methner ◽

Marion Campani ◽

Svetlana Botsyun ◽

Sebastian G. Mutz ◽

...

Keyword(s):

Sea Level ◽

Foreland Basin ◽

European Alps ◽

Molasse Basin ◽

Central Alps ◽

Pedogenic Carbonate ◽

Northern Alpine Foreland ◽

History Of ◽

Alpine Foreland ◽

Alpine Foreland Basin

Abstract. Reconstructing Oligocene-Miocene paleoelevation contributes to our understanding of the evolutionary history of the European Alps and sheds light on geodynamic and Earth’s surface processes involved in the development of Alpine topography. Despite being one of the most intensively explored mountain ranges worldwide, constraints on the elevation history of the European Alps, however, remain scarce. Here we present stable and clumped isotope geochemistry measurements to provide a new paleoelevation estimate for the mid-Miocene (~14.5 Ma) European Central Alps. We apply stable isotope δ-δ paleoaltimetry on near sea level pedogenic carbonate oxygen isotope (δ18O) records from the Northern Alpine Foreland Basin (Swiss Molasse Basin) and high-Alpine phyllosilicate hydrogen isotope (δD) records from the Simplon Fault Zone (Swiss Alps). We further explore Miocene paleoclimate and paleoenvironmental conditions in the Swiss Molasse Basin through carbonate stable (δ18O, δ13C) and clumped (Δ47) isotope data from three foreland basin sections in different alluvial megafan settings (proximal, mid-fan, and distal). Combined pedogenic carbonate δ18O values and Δ47 temperatures (30 ± 5 °C) yield a near sea level precipitation δ18Ow value of −5.8 ± 0.2 ‰ and in conjunction with the high-Alpine phyllosilicate δD record suggest that the region surrounding the SFZ attained surface elevations of > 4000 m no later than the mid-Miocene. Our near sea level δ18Ow estimate is supported by paleoclimate (iGCM Echam5-wiso) modeled δ18O values, which vary between −4.2 and −7.6 ‰ for the Northern Alpine Foreland Basin.

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Quantifying Multiple Erosion Events in the Distal Sector of the Northern Alpine Foreland Basin (North-Eastern Switzerland), by Combining Basin Thermal Modelling with Vitrinite Reflectance and Apatite Fission Track Data

Geosciences ◽

10.3390/geosciences11020062 ◽

2021 ◽

Vol 11 (2) ◽

pp. 62

Author(s):

Silvia Omodeo-Salé ◽

Yanis Hamidi ◽

Diego Villagomez ◽

Andrea Moscariello

Keyword(s):

Vitrinite Reflectance ◽

Foreland Basin ◽

Thermal Modelling ◽

North Eastern ◽

Northern Alpine Foreland ◽

Alpine Foreland ◽

Alpine Foreland Basin ◽

Stratigraphic Evolution ◽

Reflectance Data ◽

Modelling Approach

This work quantifies the amount of erosion associated with the Cretaceous and Miocene erosional unconformities recognised in the distal part of the Northern Alpine Foreland Basin (NAFB), north-eastern Switzerland. To achieve this goal, the basin thermal modelling approach is applied, calibrated by two different sets of data collected in previous studies: vitrinite reflectance (%Ro) and the temperature estimated from apatite fission tracks (AFT) data modelling. The novelty of this approach is the possibility to constrain the timing and magnitude of multiple erosion events by integrating thermal modelling with thermochronologic data. Combining these two methods allows the erosional events to be separated which would not be possible using only irreversible paleothermometers, such as vitrinite reflectance data. Two scenarios were tested, based on the data of two published thermochronology studies. For the Cretaceous unconformity, similar results are obtained for the two scenarios, both indicating that the deposition and the subsequent complete erosion of Lower Cretaceous deposits, in the order of 500–1300 m, depending on the area, are necessary, in order to attain the temperatures estimated by the thermal history modelling of AFT data. Thus, a depositional hiatus for this period is not likely. For the Miocene-Quaternary unconformity, the magnitude of erosion calculated for the two scenarios differs by 300–1400 m, depending on the AFT data considered. The two scenarios lead to a different evaluation of the subsidence and uplift rate of the study area, thus to a different interpretation of the tectono-stratigraphic evolution of this distal sector of the NAFB.

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Vertebrate microfossils from the Upper Freshwater Molasse in the Swiss Molasse Basin: Implications for the evolution of the North Alpine Foreland Basin during the Miocene Climate Optimum

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/j.palaeo.2015.02.028 ◽

2015 ◽

Vol 426 ◽

pp. 22-33 ◽

Cited By ~ 14

Author(s):

Jürg Jost ◽

Daniel Kälin ◽

Saskia Börner ◽

Davit Vasilyan ◽

Daniel Lawver ◽

...

Keyword(s):

Foreland Basin ◽

Molasse Basin ◽

The North ◽

Upper Freshwater Molasse ◽

North Alpine Foreland Basin ◽

Alpine Foreland ◽

Alpine Foreland Basin

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Volcanism and Volcanogenic Submarine Sedimentation in the Paleogene Foreland Basins of the Alps: Reassessing the Source-to-Sink Systems with an Actualist View

Geosciences ◽

10.3390/geosciences11010023 ◽

2021 ◽

Vol 11 (1) ◽

pp. 23

Author(s):

Andrea Di Capua ◽

Federica Barilaro ◽

Gianluca Groppelli

Keyword(s):

Foreland Basin ◽

Fault System ◽

Foreland Basins ◽

The North ◽

Source To Sink ◽

The Alps ◽

Alpine Foreland ◽

Alpine Foreland Basin ◽

Tectonic Lineament ◽

First Time

This work critically reviews the Eocene–Oligocene source-to-sink systems accumulating volcanogenic sequences in the basins around the Alps. Through the years, these volcanogenic sequences have been correlated to the plutonic bodies along the Periadriatic Fault System, the main tectonic lineament running from West to East within the axis of the belt. Starting from the large amounts of data present in literature, for the first time we present an integrated 4D model on the evolution of the sediment pathways that once connected the magmatic sources to the basins. The magmatic systems started to develop during the Eocene in the Alps, supplying detritus to the Adriatic Foredeep. The progradation of volcanogenic sequences in the Northern Alpine Foreland Basin is subsequent and probably was favoured by the migration of the magmatic systems to the North and to the West. At around 30 Ma, the Northern Apennine Foredeep also was fed by large volcanogenic inputs, but the palinspastic reconstruction of the Adriatic Foredeep, together with stratigraphic and petrographic data, allows us to safely exclude the Alps as volcanogenic sources. Beyond the regional case, this review underlines the importance of a solid stratigraphic approach in the reconstruction of the source-to-sink system evolution of any basin.

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