@book{LuediStehlHalleretal.2011, author = {L{\"u}di, Georges and Stehl, Thomas and Haller, Hermann W. and Prifti, Elton and Busse, Lena and Wilke, Maria and Steinicke, Lars and Schlaak, Claudia and Selting, Margret and Kern, Friederike and Couper-Kuhlen, Elizabeth and Schlaak, Claudia and Pfaff, Isolde}, title = {Sprachen in mobilisierten Kulturen : Aspekte der Migrationslinguistik}, editor = {Stehl, Thomas}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-51947}, publisher = {Universit{\"a}t Potsdam}, pages = {294}, year = {2011}, abstract = {Thematische Schwerpunkte des Sammelbandes bilden die Inhalte und die Ziele in der Erforschung und Analyse von Migrationsprozessen und die daraus resultierenden Situationen von Sprachkontakt und Kulturtransfer in Europa und {\"U}bersee. Neben der thematischen Einf{\"u}hrung in die Migrationslinguistik widmet sich der Band den migrationsbedingten Formen des Sprachkontaktes und der Sprachverwendung in Nordamerika sowie verschiedenen Sprachdynamiken in Europa. Auch der sprachliche Integrationsdruck zwischen Asien und Lateinamerika wird in diesem Band thematisiert. Neben Beitr{\"a}gen von bekannten Migrationslinguisten wie Georges L{\"u}di (Universit{\"a}t Basel) und Hermann Haller (City University, New York) finden sich theoretische und deskriptive Ans{\"a}tze zu Sprachkontakt, Sprachwandel und Sprachverfall infolge von Migration aus der Perspektive verschiedener Einzelphilologien. Mit Beitr{\"a}gen von Lena Busse, Elizabeth Couper-Kuhlen, Hermann Haller, Friederike Kern, Georges L{\"u}di, Isolde Pfaff, Elton Prifti, Claudia Schlaak, Margret Selting, Thomas Stehl, Lars Steinicke und Maria Wilke.}, language = {de} } @phdthesis{BaumannWilke2013, author = {Baumann-Wilke, Maria}, title = {Combining body wave tomography, surface wave inversion, seismic interferometry and laboratory measurements to characterize the black shales on Bornholm at different scales}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-69007}, school = {Universit{\"a}t Potsdam}, year = {2013}, abstract = {Black shales are sedimentary rocks with a high content of organic carbon, which leads to a dark grayish to black color. Due to their potential to contain oil or gas, black shales are of great interest for the support of the worldwide energy supply. An integrated seismic investigation of the Lower Palaeozoic black shales was carried out at the Danish island Bornholm to locate the shallow-lying Alum Shale layer and its surrounding formations and to characterize its potential as a source rock. Therefore, two seismic experiments at a total of three crossing profiles were carried out in October 2010 and in June 2012 in the southern part of the island. Two different active measurements were conducted with either a weight drop source or a minivibrator. Additionally, the ambient noise field was recorded at the study location over a time interval of about one day, and also a laboratory analysis of borehole samples was carried out. The seismic profiles were positioned as close as possible to two scientific boreholes which were used for comparative purposes. The seismic field data was analyzed with traveltime tomography, surface wave inversion and seismic interferometry to obtain the P-wave and S-wave velocity models of the subsurface. The P-wave velocity models which were determined for all three profiles clearly locate the Alum Shale layer between the Komstad Limestone layer on top and the L{\ae}s{\aa} Sandstone Formation at the base of the models. The black shale layer has P-wave velocities around 3 km/s which are lower compared to the adjacent formations. Due to a very good agreement of the sonic log and the vertical velocity profiles of the two seismic lines, which are directly crossing the borehole where the sonic log was conducted, the reliability of the traveltime tomography is proven. A correlation of the seismic velocities with the content of organic carbon is an important task for the characterization of the reservoir properties of a black shale formation. It is not possible without calibration but in combination with a full 2D tomographic image of the subsurface it gives the subsurface distribution of the organic material. The S-wave model obtained with surface wave inversion of the vibroseis data of one of the profiles images the Alum Shale layer also very well with S-wave velocities around 2 km/s. Although individual 1D velocity models for each of the source positions were determined, the subsurface S-wave velocity distribution is very uniform with a good match between the single models. A really new approach described here is the application of seismic interferometry to a really small study area and a quite short time interval. Also new is the selective procedure of only using time windows with the best crosscorrelation signals to achieve the final interferograms. Due to the small scale of the interferometry even P-wave signals can be observed in the final crosscorrelations. In the laboratory measurements the seismic body waves were recorded for different pressure and temperature stages. Therefore, samples of different depths of the Alum Shale were available from one of the scientific boreholes at the study location. The measured velocities have a high variance with changing pressure or temperature. Recordings with wave propagation both parallel and perpendicular to the bedding of the samples reveal a great amount of anisotropy for the P-wave velocity, whereas the S-wave velocity is almost independent of the wave direction. The calculated velocity ratio is also highly anisotropic with very low values for the perpendicular samples and very high values for the parallel ones. Interestingly, the laboratory velocities of the perpendicular samples are comparable to the velocities of the field experiments indicating that the field measurements are sensitive to wave propagation in vertical direction. The velocity ratio is also calculated with the P-wave and S-wave velocity models of the field experiments. Again, the Alum Shale can be clearly separated from the adjacent formations because it shows overall very low vP/vS ratios around 1.4. The very low velocity ratio indicates the content of gas in the black shale formation. With the combination of all the different methods described here, a comprehensive interpretation of the seismic response of the black shale layer can be made and the hydrocarbon source rock potential can be estimated.}, language = {en} } @article{Wilke2011, author = {Wilke, Maria}, title = {Die sinoperuanische Gemeinschaft in Peru}, series = {Mobilisierte Kulturen}, journal = {Mobilisierte Kulturen}, number = {2}, issn = {2192-3019}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-53682}, pages = {127 -- 149}, year = {2011}, language = {de} } @article{GruenebergerSchmidtJahnetal.2016, author = {Gr{\"u}neberger, Anja Maria and Schmidt, Christian and Jahn, Sandro and Rhede, Dieter and Loges, Anselm and Wilke, Max}, title = {Interpretation of Raman spectra of the zircon-hafnon solid solution}, series = {European journal of mineralogy}, volume = {28}, journal = {European journal of mineralogy}, publisher = {Schweizerbart}, address = {Stuttgart}, issn = {0935-1221}, doi = {10.1127/ejm/2016/0028-2551}, pages = {721 -- 733}, year = {2016}, abstract = {Zircon (ZrSiO4), hafnon (HfSiO4) and five intermediate compositions were synthesized from a Pb silicate melt. The resulting crystals were 20-300 mu m in size and displayed sector and growth zoning. Raman spectra were acquired at locations in the sample for which preceding electron microprobe (EMP) analyses revealed sufficient compositional homogeneity. The dataset documents shifts of Raman bands with changing composition. In this study, bands that have previously not been reported were found for the intermediate compositions and for pure hafnon, in particular at wavenumbers less than 200 cm(-1). For these external modes, the dataset provides new insight into the compositional dependence of their frequencies. Density-functional theory calculations support the observations and are used for a detailed interpretation of the spectra. The pitfalls of the EMP analysis along the zircon-hafnon join are highlighted.}, language = {en} } @article{KlemmeFeldhausPotapkinetal.2021, author = {Klemme, Stephan and Feldhaus, Michael and Potapkin, Vasily and Wilke, Max and Borchert, Manuela and Louvel, Marion and Loges, Anselm and Rohrbach, Arno and Weitkamp, Petra and Welter, Edmund and Kokh, Maria A. and Schmidt, Christian and Testemale, Denis}, title = {A hydrothermal apparatus for x-ray absorption spectroscopy of hydrothermal fluids at DESY}, series = {Review of scientific instruments : a monthly journal devoted to scientific instruments, apparatus, and techniques}, volume = {92}, journal = {Review of scientific instruments : a monthly journal devoted to scientific instruments, apparatus, and techniques}, number = {6}, publisher = {AIP Publishing}, address = {Melville}, issn = {0034-6748}, doi = {10.1063/5.0044767}, pages = {6}, year = {2021}, abstract = {We present a new autoclave that enables in situ characterization of hydrothermal fluids at high pressures and high temperatures at synchrotron x-ray radiation sources. The autoclave has been specifically designed to enable x-ray absorption spectroscopy in fluids with applications to mineral solubility and element speciation analysis in hydrothermal fluids in complex compositions. However, other applications, such as Raman spectroscopy, in high-pressure fluids are also possible with the autoclave. First experiments were run at pressures between 100 and 600 bars and at temperatures between 25 degrees C and 550 degrees C, and preliminary results on scheelite dissolution in fluids of different compositions show that the autoclave is well suited to study the behavior of ore-forming metals at P-T conditions relevant to the Earth's crust.}, language = {en} }