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Cruise EMB217 - The role of the bottom boundary turbulence for the transport of tracers in marine basins

The EMB217 cruise was dedicated to the DFG-Funded project ROBOTRACE (The role of bottom boundary layer turbulence for the exchange of tracer) and was the third in the project. The purpose was to sample the ROBOTRACE stations during a calm summer season. This allows to understand the seasonality of the oxygen transport in the central Baltic Sea. The sampled stations and main transect were on the eastern part of the Gotland Basin (TS1, Fig. 3.1). For the background condition during the cruise, two moorings chains, including ADCP, T, S and oxygen sensors, were deployed along the transect. Short term deployments of oxygen microprofilers, oxygen eddy-covariance and chamber landers were performed along the transect. The transect was sampled several times with a shear microstructure probe (MSS-90L) including a fast response oxygen optode and accompanied by nutrient samples taken with watersamplers mounted on a standard CTD rosette. Besides these main tasks, maintenance of the IOW longterm mooring NE and GODESS were performed and a lagrangian drifter (Jetsam, Univ. Florida) was tested for its use in the Baltic Sea.

Cruise EMB265 - Three-dimensional acoustic mapping of small-scale physical processes in the North Sea and Baltic Sea

During this short cruise, we explored the potential of acoustic echo sounding techniques (wideband single-beam and multibeam systems) for the quantitative investigation of turbulence and other small-scale processes in the water column. These activities were embedded in the research project „Four dimensional Research applying Modeling and Observations for the Sea and Atmosphere“ (FORMOSA), funded by the German Leibniz-Association (WGL) in the framework of the national funding line “Cooperative Excellence”. The cruise took place in May 2021 in the Kattegat region and the western Baltic Sea (Arkona Basin). Our activities focused on the mixing of salty North Sea waters and brackish outflow waters from the Baltic Sea in the Kattegat region with the help of turbulence microstructure and acoustic observations. Measurements were conducted by scientists from IOW in collaboration with project partners from Stockholm University (Sweden) and an additional engineering group from Rostock University (Germany).

High-angular resolution electron backscatter diffraction data (HR-EBSD) from olivine and quartz

This dataset is supplemental to the paper Wallis et al. (2019) and contains data derived from distortion of crystal lattices measured using conventional electron backscatter diffraction (EBSD) and high-angular resolution electron backscatter diffraction (HR-EBSD). The datasets include lattice misorientation, elastic-strain heterogeneity, residual-stress heterogeneity, and densities of geometrically necessary dislocations in olivine and quartz. We intend the data and associated paper to demonstrate key aspects of the HR-EBSD technique and to draw comparisons with conventional EBSD. As the paper by Wallis et al. (2019) is a review paper, several of the datasets have also been present in, or are otherwise related to, additional previous publications listed below .Data are provided as 55 tab delimited .txt files organised by the figure in which they appear within Wallis et al. (2019). Data types are indicated in the file names. Please consult the data description file for detailed explanations.

Mechanical and microstructural data used in the article Pijnenburg et al., Deformation behaviour of sandstones from the seismogenic Groningen gas field: Role of inelastic versus elastic mechanisms

Hydrocarbon or groundwater production from sandstone reservoirs can result in surface subsidence and induced seismicity. Subsidence results from combined elastic and inelastic compaction of the reservoir due to a change in the effective stress state upon fluid extraction. The magnitude of elastic compaction can be accurately described using poroelasticity theory. However inelastic or time-dependent compaction is poorly constrained. We use sandstones recovered by the field operator (NAM) from the Slochteren gas reservoir (Groningen, NE Netherlands) to study the importance of elastic versus inelastic deformation processes upon simulated pore pressure depletion. We conducted conventional triaxial tests under true in-situ conditions of pressure and temperature. To investigate the effect of applied differential stress (σ1 – σ3 = 0 - 50 MPa) and initial sample porosity (φi = 12 – 25%) on instantaneous and time-dependent inelastic deformation, we imposed multiple stages of axial loading and relaxation.The obtained data include:1) Mechanical data obtained in conventional triaxial compression experiments performed on reservoir sandstone. In these experiments, we imposed multiple stages of active loading, each followed by 24 hours of stress relaxation.2) Microstructural data obtained on undeformed and deformed samples.

Randomized rock microstructures - Collection of raster data, properties, and finite element simulation package

This collection contains 10500 computationally generated, randomised 2D microstructures, their geometrical and electrical properties, and the Matlab software package used to calculate these properties. The two-phase microstructures (mineral matrix, pore space) represent three different pore space types (microfracture networks, intergranular pore space, oomoldic pore space) and are organised into 35 ensembles - with common modelling parameters - of 100 individual microstructure realisations each. For all realisations, several geometrical properties (percolation, total porosity, connected porosity, isolated porosity, surface area, fractal dimension) and physical properties (formation factor from electrical resistivity, electrical tortuosity) are given. The collection also includes a Matlab-based finite element simulation package derived from the FEMALY library, which can be used to compute the properties of any given 2D raster microstructure.

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