Other language confidence: 0.8802967859568929
Ziel des Vorhabens ist die Erforschung des Rift-Prozesses in kontinentaler Kruste und die dabei beginnende Ozeanbodenbildung. Im Einzelnen sollen die Wechselwirkungen zwischen Tektonik, Magmatismus und Hydrothermalismus beim Rifting der Kontinentalkruste im Woodlark Becken durch Beprobung entlang und quer zur Spreizungsachse und hochauflösende Kartierung des Meeresbodens und der Wassersäule mittels AUV (Autonomous Underwater Vehicle) entschlüsselt werden. Durch strukturgeologische, bathymetrische, vulkanologische, geochemische und geochronologische Methoden soll das Verhalten des kontinentalen Lithosphärenmantels bei der Öffnung eines Kontinentes (hier Papua Neuguineas) untersucht werden. Die Beprobung der verschiedenen Strukturen erfolgt dabei mittels Dredge und Vulkanitstoßrohr. Um die Öffnung direkt zu beobachten und die Proportionen von ozeanischer und kontinentaler Kruste in der aktiven Riftzone abzuschätzen, werden im Bereich der propagierenden Spreizung mikrobathymetrische Profile mittels AUV durchgeführt. Um den Einfluss des Riftings auf den Hydrothermalismus wird sowohl im Bereich der propagierenden Spreizungsachse als auch im Bereich der zentralen und östlichen Spreizungszone nach Anzeichen hydrothermaler Aktivität gesucht und anschließend beprobt. Die geplanten Untersuchungen sind in Zusammenhang mit der Untersuchung der Prozesse in der kontinentalen und ozeanischen Kruste relevant und fügen sich damit in die forschungspolitischen Schwerpunkte des BMBF ein. Das Vorhaben ist wissenschaftlich aktuell und der Antragsteller ist qualifiziert entsprechende Untersuchungen erfolgreich durchzuführen. Der Fahrtbericht wird als Hardcopy bei der Technischen Informationsbibliothek in Hannover vorliegen und die Wochenberichte der Forschungsfahrt finden sich auf der Internetplattform des FS SONNE (BGR).
This dataset contains geological data from the Western Afar Margin (WAM) in East Africa. These in-clude (reprocessed) earthquake data from previously published surveys and publically accessible databases (Keir et al. 2006, 2009; Ebinger et al 2008; Belachew et al. 2011; Illsley-Kemp et al. 2018a, b and the GCMT Project 2019), which form the basis for Seismic Moment Release (SMR) mapping as well as and tectonic stress analysis, revealing the location and intensity of ongoing deformation, as well as the direction of current extension, respectively. In addition, we present various large-scale maps of the WAM, depicting faults, dikes and sedimentary basins as interpreted from topographic indicators.Field data (GPS locations, fault measurements, field book), acquired during two field campaigns in Ethiopia and Eritrea are included, as well as the kinematic interpretation of the field data using Wintensor software (Delvaux & Sperner 2003). These results are combined with previously published kinematic data from Eritrea and Ethiopia (i.e. the northernmost and southern segments of the WAM, studied by Chorowicz et al. 1999 and Sani et al. 2017), yielding the first coherent overview of (current) tectonic deformation covering the whole margin. Note that we also provide a field book with detailed descriptions of every outcrop, including photographs. Finally, we include unique borehole data from the Kobo graben area, based on well logs from irrigation projects kindly provided to us by local geologists during the Ethiopian field campaign (see section 2.5 and the acknowledgements) .Applications and interpretation of the data provided in this dataset can be found in Zwaan et al. (in review). For more description please refer to the data description. This data publication consists of 90 files: (digital) maps, GPS locations, tables, text and Wintensor files. A detailed overview of all files within this dataset is given in the List of Files.
Geochronological data allowed constraining the tectonostratigraphic evolution of a European terrane stacked in the Western Alps and consisting of a Palaeozoic basement overlain by a Mesozoic metasedimentary cover. Four samples belonging to the basement have been analyzed. They correspond to two metasediments (VS113: 7°9'0"E, 45°9'8"N; VS114: 7°7'26"E, 45°9'0"N) and two orthogneisses (VS60: 7°9'8"E, 45°9'5"N; VS77 7°15'52"E, 45°6'54"N). Zircons from the studied samples were separated and analyzed to obtain the younger population age of the metasediments, and the crystallization age of the orthogneiss.
In this dataset we provide top-view photos and perspective photos (to create topographic data, i.e. Digital Elevation Models, DEMs) documenting analogue model deformation. For more details on modelling setup, experimental series Wang et al. (2021), to which this dataset is supplementary material. For details on analogue materials refer to Del Ventisette et al., 2019, Maestrelli et al. (2020). The analogue modelling experiments were carried out at the TOOLab (Tectonic Modelling Laboratory) of the Institute of Geosciences and Earth Resources of the National Research Council of Italy, Italy, and the Department of Earth Sciences of the University of Florence. The laboratory work that produced these data was supported by the European Plate Observing System (EPOS) and by the Joint Research Unit (JRU) EPOS Italia. Additional analysis, following the original work, was supported by the “Monitoring Earth’s Evolution and Tectonics” (MEET) project
This data set includes the results of high-resolution digital elevation models (DEM) and digital image correlation (DIC) analysis applied to analogue modelling experiments. Twenty generic analogue models are extended on top of a rubber sheet. Two benchmark experiments are also reported. Detailed descriptions of the experiments can be found in Liu et al. (submitted) to which this data set is supplement. The data presented here are visualized as topography and the horizontal cumulative surface strain (principal strain and slip rake).
This data set includes videos depicting the surface evolution of 29 analogue models on crustal extension, as well as 4D CT imagery (figures and videos) of two of these experiments. The experiments examined the influence of the method for driving extension (orthogonal or rotational) on the interaction between rift segments using a brittle-viscous set-up. All experiments were performed at the Tectonic Modelling Laboratory of the University of Bern, Bern, Switzerland (UB). Brittle and viscous layers are both 4 cm thick, extension velocities are 8 mm/h so that a model duration of 5 h yields a total extension of 40 mm (e = ca. 13%, given an initial model width of ca. 30 mm). Next to the mode of extension (orthogonal or rotational), we also test the effect of the degree of onderlap (angle φ). Detailed descriptions of the experiments and monitoring techniques can be found in Zwaan et al. (2020).
This dataset shows the original data of a series of enhanced-gravity (centrifuge) analogue models, which were performed to test the influence of the pre-existing fabrics in the brittle upper crust on the evolution of structures resulting from oblique rifting. The obliquity of the rift (i.e., the angle between the rift axis and the direction of extension) was kept constant at 30° in all the models. The main variable of this experimental series was the orientation of the pre-existing fabrics (indicated as the angle between the trend of the fabric and the orthogonal to extension), which varied from 0° to 90° (i.e., from orthogonal to parallel to the extension direction). The inherited discontinuities were reproduced by cutting with a knife through the top brittle layer of models. An overview of the experimental series is shown in Table 1. In this dataset, four different data types are provided for further analysis: 1) Top-view photos of model deformation, taken at different time intervals and showing the deformation process of each model; they can be used to interpret the geometrical characteristics of rift-related faults; 2) Digital Elevation Models (DEMs) used to reconstruct the 3D deformation of the analogue models, allowing for quantitative analysis of the fault pattern. 3) Movies of model deformation, built from top-view photos, which help to visualize the evolution of model deformation; 4) Faults line-drawings to be used for statistical quantification of rift-related structures. Further information on the modelling strategy and setup can be found in the publication associated to this dataset and in Corti (2012), Philippon et al. (2015), Maestrelli et al. (2020), Molnar et al. (2020), Zwaan et al. (2021), Zou et al. (2023). Materials used to perform these enhanced-gravity analogue models were described in Montanari et al. (2017), Del Ventisette et al. (2019) and Zwaan et al. (2020).
This data set includes videos depicting the surface evolution (time-lapse photography, topography data and Digital Image Correlation [DIC] analysis) of 11 analogue models, divided in three model series (A, B and C), simulating rifting and subsequent inversion tectonics. In these models we test how orthogonal or oblique extension, followed by either orthogonal or oblique compression, as well as syn-rift sedimentation, influenced the reactivation of rift structures and the development of new inversion structures. We compare these models with an intracontinental inverted basin in NE Brazil (Araripe Basin). All experiments were performed at the Tectonic Modelling Laboratory of the University of Bern (UB). We used an experimental set-up involving two long mobile sidewalls, two rubber sidewalls (fixed between the mobile walls, closing the short model ends), and a mobile and a fixed base plate. We positioned a 5 cm high block consisting of an intercalation of foam (1 cm thick) and Plexiglas (0.5 cm thick) bars on the top of the base plates. Then we added layers of viscous and brittle analogue materials representing the ductile and brittle lower and upper crust in our experiments, which were 3 cm and 6 cm thick, respectively. A seed made of the same viscous material was positioned at the base of the brittle layer, in order to localize the formation of an initial graben in our models. The standard model deformation rate was 20 mm/h, over a duration of 2 hours for a total of 40 mm of divergence, followed by 2 hours of convergence at the same rate (except for Models B3 and C3, since the oblique rifting did not create space for 40 mm of orthogonal inversion). For syn-rift sedimentation, we applied an intercalation of feldspar and quartz sand in the graben. Model parameters and detailed description of model set-up are summarized in Table 1, and results and their interpretation can be found in Richetti et al. (2023).
This data set includes images and videos depicting the evolution of deformation and topography of 17 analogue experiments c passive margin development, to better understand the ongoing tectonics along the western margin of Afar, East Africa. The tectonic background that forms the basis for the experimental design is found in Zwaan et al. 2019 and 2020a-b, and references therein. The experiments, in an enhanced gravity field in a large-capacity centrifuge, examined the influence of brittle layer thickness, strength contrast, syn-rift sedimentation and oblique extension on a brittle-viscous system with a strong and weak viscous domain. All experiments were performed at the Tectonic Modelling Laboratory of of the Istituto di Geoscience e Georisorse - Consiglio Nazionale delle Ricerche (CNR-IGG) and of the Earth Sciences Department of the University of Florence (CNR/UF). The brittle layer (sand) thickness ranged between 6 and 20 mm, the underlying viscous layer, split in a competent and weak domain (both viscous mixtures), was always 10 mm thick. Asymmetric extension was applied by removing a 1.5 mm thick spacer at the side of the model at every time step, allowing the analogue materials to spread when enhanced gravity was applied during a centrifuge run. Differential stretching of the viscous material creates flexure and faulting in the overlying brittle layer. Total extension amounted to 10.5 mm over 7 intervals for Series 1 models that aimed at understanding generic passive margin development in a generic orthogonal extension setting, whereas up to 16.5 mm of extension was applied for the additional Series 2 models aiming at reproducing the tectonic phases in Afar. In models involving sedimentation, sand was filled in at time steps 2, 4 and 6 (i.e. after 3, 6 and 9 mm of extension). Detailed descriptions of the experiments, monitoring techniques and tectonic interpretation of the model results are presented in Zwaan et al. (2020c) to which these data are supplementary.
This data set includes videos depicting the surface evolution (time-lapse photographs and Particle Image Velocimetry or PIV analysis) of 38 analogue models, in five model series (A-E), simulating rift tectonics. In these experiments we examined the influence of differently oriented mantle and crustal weaknesses on rift system development during multiphase rifting (i.e. rifting involving changing divergence directions or -rates) using brittle-viscous set-ups. All experiments were performed at the Tectonic Modelling Laboratory of the University of Bern (UB). The brittle and viscous layers, representing the upper an lower crust, were 3 cm and 1 cm thick, respectively, whereas a mantle weakness was simulated using the edge of a moving basal plate (a velocity discontinuity or VD). Crustal weaknesses were simulated using “seeds” (ridges of viscous material at the base of the brittle layers that locally weaken these brittle layers). The divergence rate for the Model A reference models was 20 mm/h so that the model duration of 2:30 h yielded a total divergence of 5 cm (so that e = 17%, given an initial model width of ca. 30 cm). Multiphase rifting model series B and C involved both a slow (10 mm/h) and fast (100 mm/h) rifting phase of 2.5 cm divergence each, for a total of 5 cm of divergence over a 2:45 h period. Multiphase rifting models series D and E had the same divergence rates (20 mm/h) as the Series A reference models, but involved both an orthogonal (α = 0˚) and oblique rifting (α = 30˚) phase of 2.5 cm divergence each, for a total of 5 cm of divergence over a 2:30 h period. In our models the divergence obliquity angle α was defined as the angle between the normal to the central model axis and the direction of divergence. The orientation and arrangements of the simulated mantle and crustal weaknesses is defined by angle θ (defined as the direction of the weakness with respect to the model axis. An overview of model parameters is provided in Table 1, and detailed descriptions of the model set-up and results, as well as the monitoring techniques can be found in Zwaan et al. (2021).
| Organisation | Count |
|---|---|
| Bund | 1 |
| Wissenschaft | 14 |
| Type | Count |
|---|---|
| Förderprogramm | 1 |
| unbekannt | 14 |
| License | Count |
|---|---|
| Offen | 15 |
| Language | Count |
|---|---|
| Deutsch | 1 |
| Englisch | 14 |
| Resource type | Count |
|---|---|
| Keine | 14 |
| Webseite | 1 |
| Topic | Count |
|---|---|
| Boden | 9 |
| Lebewesen und Lebensräume | 6 |
| Luft | 1 |
| Mensch und Umwelt | 13 |
| Wasser | 10 |
| Weitere | 15 |