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An essential part of the collaborative research project H2STORE (hydrogen to store), which is funded by the German government, was a comparison of various analytical methods for characterizing reservoir sandstones from different stratigraphic units. In this context Permian, Triassic and Tertiary reservoir sandstones were analysed. Rock core materials, provided by RWE Gasspeicher GmbH (Dortmund, Germany), GDF Suez E&P Deutschland GmbH (Lingen, Germany), E.ON Gas Storage GmbH (Essen, Germany) and RAG Rohöl-Aufsuchungs Aktiengesellschaft (Vienna, Austria), were processed by different laboratory techniques; thin sections were prepared, rock fragments were crushed and cubes of 1 cm edge length and plugs 3 to 5 cm in length with a diameter of about 2.5 cm were sawn from macroscopic homogeneous cores. With this prepared sample material, polarized light microscopy and scanning electron microscopy, coupled with image analyses, specific surface area measurements (after Brunauer, Emmet and Teller, 1938; BET), He-porosity and N2-permeability measurements and high-resolution microcomputer tomography (μ-CT), which were used for numerical simulations, were applied. All these methods were practised on most of the same sample material, before and on selected Permian sandstones also after static CO2 experiments under reservoir conditions. A major concern in comparing the results of these methods is an appraisal of the reliability of the given porosity, permeability and mineral-specific reactive (inner) surface area data. The CO2 experiments modified the petrophysical as well as the mineralogical/geochemical rock properties. These changes are detectable by all applied analytical methods. Nevertheless, a major outcome of the high-resolution μ-CT analyses and following numerical data simulations was that quite similar data sets and data interpretations were maintained by the different petrophysical standard methods. Moreover, the μ-CT analyses are not only time saving, but also non-destructive. This is an important point if only minor sample material is available and a detailed comparison before and after the experimental tests on micrometre pore scale of specific rock features is envisaged.

The Rotliegend saline lake periodically covered wide areas of the Southern Permian Basin in Northwest Europe during the Permian. The sedimentology, mineralogy and geochemistry of lake deposits were studied to document very high frequency lake level fluctuations and to evaluate their triggers. Increased precipitation and marine ingressions into the basin resulted in lake extension. Increased run-off is documented by intercalated fluvial deposits in low-salinity deposits of the lake. Because lake deposits reflect mainly deposition in relatively wet climate phases, they are not correlatable to halite deposits in other basin areas. Decreased precipitation is followed by shrinkage of the lake, desiccation at its margins, and higher lake salinity due to concentration of the brine. Carbonate and anhydrite contents of lake deposits increased considerably before the areas fell dry, but halite is not preserved in the study area. Falling lake level is also reflected by the occurrence of wave ripples, reflecting decreased water depth and finally by desiccation and formation of evaporite crusts. Not only the mineralogical content, but also the colour of lake claystones changes with varying salinity. Anhydrite- and carbonate-free red claystones were replaced by violet to green and grey anhydritic and calcareous claystone or marls with increasing salinity. The amount of boron adsorbed on illite also corresponds to changes in salinity and can therefore be used as a palaeosalinity indicator. Rare earth element concentrations within lake deposits do not reflect variations in salinity but different palaeogeographical settings. Marine ingressions into the lake are neither reflected by the amount of boron adsorbed onto illite nor by rare earth element contents of the lake deposits. Highly saline deposits are partly characterised by intensive deformation, which can be interpreted as seismites or dissolution breccias.

To investigate if changes in low-to-high frequency ratio (LF/HF), low frequency (LF) and high frequency (HF) heart rate variability reflect autonomic regulation during spinal anaesthesia (SA) in pregnant women scheduled for elective Caesarean section.Prospective clinical trial. Systolic blood pressure (SBP) and heart rate variability were analysed at baseline, 5 min after SA and 15 min after SA. Patients were assigned by baseline LF/HF. Group LF/HF2.5 (n= 52) was compared to group LF/HF2.5 (n= 48). Non-parametric tests for statistical analysis.Group LF/HF2.5 showed a significant decrease in LF/HF and LF as well as an increase in HF during SA (median, range): baseline LF/HF [4.0 (3.2/4.8)] decreased to 2.3 (1.3/3.4) at event 15 min after SA (P0.001). Baseline LF = 59(43/71)% decreased to 40 (27/55)% at event 15 min after SA (P0.05). Baseline HF = 15(13/22)% increased to 26(15/41)% at event 15 min after SA (P0.05). In contrast, group LF/HF2.5 demonstrated only moderate changes in LF/HF, LF and HF during SA. SBP decreased significantly in group LF/HF2.5 (median and range) lowest SBP group LF/HF2.5: 80 (50/127 mmHg vs. group LF/HF2.5: 109 (104/142) mmHg, P0.001. Decrease of SBP before and after SA was correlated with a decrease in LF/HF, LF, and HF, respectively: LF/HF - SBP: r= 0.30, r(2)= 0.09, P0.001; LF - SBP: r= 0.25, r(2)= 0.06, P0.05, HF, NS.Changes in heart rate variability parameters in the course of SA may reflect a decrease in sympathetic activity and relative increase in parasympathetic activity as a result of the block. In the course of SA, the more pronounced the changes in heart rate variability were the more distinct the hypotension.

The large scale storage of energy is a great challenge arising from the planned transition from nuclear and CO2-emitting power generation to renewable energy production, by e.g. wind, solar, and biomass in Germany. The most promising option for storing large volumes of excess energy produced by such renewable sources is the usage of underground porous rock formations as energy reservoirs. Some new technologies are able to convert large amounts of electrical energy into a chemical form, for example into hydrogen by means of water electrolysis. Porous formations can potentially provide very high hydrogen storage capacities. Several methods have to be studied including high hydrogen diffusivity, the potential reactions of injected hydrogen, formation fluids, rock composition, and the storage complex. Therefore, in August 2012 the collaborative project H2STORE ("hydrogen to store") started to investigate the feasibility of using burial clastic sediments of depleted gas reservoirs as well as recently used gas storage sites as potential hydrogen storage media. In Germany, such geological structures occur at various geographic sites and different geological strata. These deposits are characterized by different geological-tectonic evolution and mineralogical composition, mainly depending on palaeogeographic position and diagenetic burial evolution. Resulting specific sedimentary structures and mineral parageneses will strongly control formation fluid pathways and associated fluid-rock/mineral reactions. Accordingly, H2STORE will analyze sedimentological, petrophysical, mineralogical/geochemical, hydrochemical, and microbiological features of the different geological strata and the German locations to evaluate potential fluid-rock reactions induced by hydrogen injection. Such potential reactions will be experimentally induced in laboratory runs, as analogues for naturally occurring processes in deep seated reservoirs. Finally, rock data determined before and after these experiments will be used as major input parameters for numerical modelling of mineralogical and microbiological reactions. Such reactions are expected to have a strong affect on rock porosity-permeability evolution and therefore the characteristics of flow processes in reservoir and the barrier properties of sealing rocks. The special topic of this study will be the modelling of hydrogen propagation in the subsurface reservoir formation supplemented by its mixing with the residual gases as well as the simulation of coupled bio-dynamic processes and of reactive transport in porous media. These numerical simulations will enable the transfer of experimental results from the laboratory runs to the field-scale and the formulation of the requirements for hydrogen storage in converted gas fields. Thus, the major objectives of H2STORE are to obtain fundamental data on the behaviour of clastic sediments in the presence of formation fluids and injected hydrogen, its impact on petrophysical features and the development of the most realistic modelling for proposed and experimentally induced rock alteration as well as complex gas mixing processes in potential geological hydrogen reservoirs. Moreover these results will be used when discussing the possibility of "green" eco-methane generation by hydrogen and carbon dioxide interaction in the geological underground.

The source of organic acids is commonly attributed to the early maturation of kerogen in source rocks. Organic acids are frequently interpreted as cause of burial related secondary porosity. Major deficiencies of this concept are insufficient oxygen in th

We investigated a 10 x 20 km area approx. 40 km north of Hannover using 3D reflection seismics. The Top Rotliegend surface in this area lies between –4600 m and –4150 m elevation (see Fig.). Rotliegend sandstones are gas plays, but low permabilibities (< 0,6 mD) hinder extraction. We differenciated the following types of faults from seismic analysis: 1) N-S striking normal faults, 2) a NW-SE striking strike-slip fault, and 3) late NE-SW striking faults with along-strike throws of 0-90 m, 0-150 m and 0-50 m, respectively. In the decimetre sandstone/shale units of the Upper Rotliegend these throws tend to increase across-fault connectivity. We suggest type 1 and 2 faults developed in a synsedimentary, dextral transtensive regime. Only faults with more than 50 m throw extend down to the Carboniferous and offer shortcuts for hydrocarbon flow. A compilation of paleostresses from published data (cf. Ziegler 1990), shows all the faults were under dilation during the Triassic and Jurassic, but sealing from Barremian to Eocene times. This is substantiated by the exclusive Jurassic ages of chlorite and illite diagenesis. Top Rotliegend surface of the ‘Tight Gas’ area. Faults are black. Reference: Ziegler, P.A. (1990) Geological Atlas of Western and Central Europe

This 1D/2D petroleum system modelling study intended to reconstruct the temperature, maturation, migration and accumulation history within the „Tight Gas Area“ on the southern edge of the Pompeckj Block in northern Germany. To better understand hydrocarbon migration and to generate a more reliable predictive model of reservoir characteristics, we integrated detailed information from (i) sedimentological analysis of core and log data, and (ii) a structural reconstruction of the Rotliegend reservoir horizons. One cross section and 12 wells were examined using the 1D/2D simulation software PetroMod® 7.1 of IES GmbH, Jülich; subsequently the results of the 1D modelling were incorporated in the 2D model. The W-E section connects well-known gas fields of the Nordhannover concession and runs perpendicular to the prevalent N-S striking horst-and-graben structures within the Paleozoic rocks. The depth to the major source rocks within the area, the coal-bearing Westphalian strata, varies between 5800 m and around 4700 m in some areas (e.g. Top Westphalian B). Along the section, a pre-Permian erosion of between 400 to 1200 m of Upper Carboniferous sediments was assumed, the actual amount depending on the position relative to horst and grabens. During the Upper Carboniferous and the Rotliegend the temperatures within Westphalian B and Lower Westphalian C sediments remained below 100°C and 75°C, respectively. The temperatures within these sediments increased by about 50°C, before they decreased again to 125°C and 100°C, respectively, due to the Late Jurassic inversion. During on-going burial in the Upper Cretaceous, temperatures rose until they reached their present-day values of about 175°C in Lower Westfalian C, 210°C in Westfalian B, and more than 250°C in Namurian C sediments. According to the temperature history, the maturation of organic matter within these rocks occurred in two important stages. During the Triassic, vitrinite reflectance reached values of 1.5% and 1.0% in Westphalian B and Lower Westphalian C sediments, respectively. The second period of intense maturation was coeval with enhanced subsidence during the Upper Cretaceous, when vitrinite reflectance within Westfalian B and C sediments increased from to 3.0% and about 2.2%, respectively. Maturity within the horst block sediments remained lower by about 1.0%. Within Westphalian B sediments gas generation started during the Middle Triassic and lasted until the Late Tertiary. These rocks became overmature whilst Lower Westfalian C rocks generated gas until the present time and transformed 60-90% of their convertible kerogen into hydrocarbons, the actual amount depending on the structural position. During the Jurassic and the Triassic, when the regional stress field allowed N-S striking faults to be dilatant and to act as migration pathways, high gas columns along the fault zones led to a breakthrough and loss of gas, where thinned Zechstein salt exists.

Unter kritischer Wurdigung der einschlagigen Literatur wird uber einen Fall von Meningitis cerebrospinalis purulenta, hervorgerufen durch den Micrococcus catarrhalis (Pfeiffer), berichtet und derselbe hinsichtlich der bakteriellen Atiologie und der Pathogenese ausfuhrlich kritisch beleuchtet.

Es wird uber 3 weitere Sippen von paroxysmaler Lahmung berichtet, von denen 2 eine Ubertragung der Krankheit von Generation zu Generation erkennen lassen, so das hieraus angesichts der grosen Seltenheit des Leidens auf einen einfach dominanten Erbgang geschlossen werden kann. In der 3. Sippe konnte nur ein einziger Fall von paroxysmaler Lahmung festgestellt werden: der Merkmalstrager blieb also in seiner Sippe isoliert. Unter kritischer Berucksichtigung der Literatur wird die Auffassung vertreten, das bisher nichts dafur spricht, das die wiederholt beobachteten sporadischern Falle exogen bedingt werden. Die Annahme, das auch die sporadische paroxysmale Lahmung erbbedingt ist, wird fur durchaus moglich gehalten. Danach ware mit der Moglichkeit zu rechnen, das es zum mindesten 2 Biotypen des klinisch einheitlichen Krankheitsbildes der paroxysmalen Lahmung gibt.

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