@article{AbdrakhmatovWalkerCampbelletal.2016, author = {Abdrakhmatov, Kanatbek E. and Walker, R. T. and Campbell, G. E. and Carr, A. S. and Elliott, A. and Hillemann, Christian and Hollingsworth, J. and Landgraf, Angela and Mackenzie, D. and Mukambayev, A. and Rizza, M. and Sloan, R. A.}, title = {Multisegment rupture in the 11 July 1889 Chilik earthquake (M-w 8.0-8.3), Kazakh Tien Shan, interpreted from remote sensing, field survey, and paleoseismic trenching}, series = {Journal of geophysical research : Solid earth}, volume = {121}, journal = {Journal of geophysical research : Solid earth}, publisher = {American Geophysical Union}, address = {Washington}, issn = {2169-9313}, doi = {10.1002/2015JB012763}, pages = {4615 -- 4640}, year = {2016}, abstract = {The 11 July 1889 Chilik earthquake (M-w 8.0-8.3) forms part of a remarkable sequence of large earthquakes in the late nineteenth and early twentieth centuries in the northern Tien Shan. Despite its importance, the source of the 1889 earthquake remains unknown, though the macroseismic epicenter is sited in the Chilik valley, similar to 100 km southeast of Almaty, Kazakhstan (similar to 2 million population). Several short fault segments that have been inferred to have ruptured in 1889 are too short on their own to account for the estimated magnitude. In this paper we perform detailed surveying and trenching of the similar to 30 km long Saty fault, one of the previously inferred sources, and find that it was formed in a single earthquake within the last 700 years, involving surface slip of up to 10 m. The scarp-forming event, likely to be the 1889 earthquake, was the only surface-rupturing event for at least 5000 years and potentially for much longer. From satellite imagery we extend the mapped length of fresh scarps within the 1889 epicentral zone to a total of similar to 175 km, which we also suggest as candidate ruptures from the 1889 earthquake. The 175 km of rupture involves conjugate oblique left-lateral and right-lateral slip on three separate faults, with step overs of several kilometers between them. All three faults were essentially invisible in the Holocene geomorphology prior to the last slip. The recurrence interval between large earthquakes on any of these faults, and presumably on other faults of the Tien Shan, may be longer than the timescale over which the landscape is reset, providing a challenge for delineating sources of future hazard.}, language = {en} } @phdthesis{Abon2015, author = {Abon, Catherine Cristobal}, title = {Radar-based rainfall retrieval for flood forecasting in a meso-scale catchment}, school = {Universit{\"a}t Potsdam}, pages = {93 S.}, year = {2015}, language = {en} } @article{AbonKneisCrisologoetal.2016, author = {Abon, Catherine Cristobal and Kneis, David and Crisologo, Irene and Bronstert, Axel and David, Carlos Primo Constantino and Heistermann, Maik}, title = {Evaluating the potential of radar-based rainfall estimates for streamflow and flood simulations in the Philippines}, series = {GEOMATICS NATURAL HAZARDS \& RISK}, volume = {7}, journal = {GEOMATICS NATURAL HAZARDS \& RISK}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {1947-5705}, doi = {10.1080/19475705.2015.1058862}, pages = {1390 -- 1405}, year = {2016}, abstract = {This case study evaluates the suitability of radar-based quantitative precipitation estimates (QPEs) for the simulation of streamflow in the Marikina River Basin (MRB), the Philippines. Hourly radar-based QPEs were produced from reflectivity that had been observed by an S-band radar located about 90 km from the MRB. Radar data processing and precipitation estimation were carried out using the open source library wradlib. To assess the added value of the radar-based QPE, we used spatially interpolated rain gauge observations (gauge-only (GO) product) as a benchmark. Rain gauge observations were also used to quantify rainfall estimation errors at the point scale. At the point scale, the radar-based QPE outperformed the GO product in 2012, while for 2013, the performance was similar. For both periods, estimation errors substantially increased from daily to the hourly accumulation intervals. Despite this fact, both rainfall estimation methods allowed for a good representation of observed streamflow when used to force a hydrological simulation model of the MRB. Furthermore, the results of the hydrological simulation were consistent with rainfall verification at the point scale: the radar-based QPE performed better than the GO product in 2012, and equivalently in 2013. Altogether, we could demonstrate that, in terms of streamflow simulation, the radar-based QPE can perform as good as or even better than the GO product - even for a basin such as the MRB which has a comparatively dense rain gauge network. This suggests good prospects for using radar-based QPE to simulate and forecast streamflow in other parts of the Philippines where rain gauge networks are not as dense.}, language = {en} } @article{AbouserieZehbeMetzneretal.2017, author = {Abouserie, Ahed and Zehbe, Kerstin and Metzner, Philipp and Kelling, Alexandra and G{\"u}nter, Christina and Schilde, Uwe and Strauch, Peter and K{\"o}rzd{\"o}rfer, Thomas and Taubert, Andreas}, title = {Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior}, series = {European journal of inorganic chemistry : a journal of ChemPubSoc Europe}, journal = {European journal of inorganic chemistry : a journal of ChemPubSoc Europe}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1434-1948}, doi = {10.1002/ejic.201700826}, pages = {5640 -- 5649}, year = {2017}, abstract = {Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.}, language = {en} } @article{AbouserieZehbeMetzneretal.2017, author = {Abouserie, Ahed and Zehbe, Kerstin and Metzner, Philipp and Kelling, Alexandra and G{\"u}nter, Christina and Schilde, Uwe and Strauch, Peter and K{\"o}rzd{\"o}rfer, Thomas and Taubert, Andreas}, title = {Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior}, series = {European journal of inorganic chemistry : a journal of ChemPubSoc Europe}, journal = {European journal of inorganic chemistry : a journal of ChemPubSoc Europe}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1434-1948}, doi = {10.1002/ejic.201700826}, pages = {5640 -- 5649}, year = {2017}, abstract = {Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.}, language = {en} } @article{AcostaSchildgenClarkeetal.2015, author = {Acosta, Veronica Torres and Schildgen, Taylor F. and Clarke, Brian A. and Scherler, Dirk and Bookhagen, Bodo and Wittmann, Hella and von Blanckenburg, Friedhelm and Strecker, Manfred}, title = {Effect of vegetation cover on millennial-scale landscape denudation rates in East Africa}, series = {Lithosphere}, volume = {7}, journal = {Lithosphere}, number = {4}, publisher = {American Institute of Physics}, address = {Boulder}, issn = {1941-8264}, doi = {10.1130/L402.1}, pages = {408 -- 420}, year = {2015}, abstract = {The mechanisms by which climate and vegetation affect erosion rates over various time scales lie at the heart of understanding landscape response to climate change. Plot-scale field experiments show that increased vegetation cover slows erosion, implying that faster erosion should occur under low to moderate vegetation cover. However, demonstrating this concept over long time scales and across landscapes has proven to be difficult, especially in settings complicated by tectonic forcing and variable slopes. We investigate this problem by measuring cosmogenic Be-10-derived catchment-mean denudation rates across a range of climate zones and hillslope gradients in the Kenya Rift, and by comparing our results with those published from the Rwenzori Mountains of Uganda. We find that denudation rates from sparsely vegetated parts of the Kenya Rift are up to 0.13 mm/yr, while those from humid and more densely vegetated parts of the Kenya Rift flanks and the Rwenzori Mountains reach a maximum of 0.08 mm/yr, despite higher median hillslope gradients. While differences in lithology and recent land-use changes likely affect the denudation rates and vegetation cover values in some of our studied catchments, hillslope gradient and vegetation cover appear to explain most of the variation in denudation rates across the study area. Our results support the idea that changing vegetation cover can contribute to complex erosional responses to climate or land-use change and that vegetation cover can play an important role in determining the steady-state slopes of mountain belts through its stabilizing effects on the land surface.}, language = {en} } @article{AdhikariGlombitzaNickeletal.2016, author = {Adhikari, Rishi Ram and Glombitza, Clemens and Nickel, Julia C. and Anderson, Chloe H. and Dunlea, Ann G. and Spivack, Arthur J. and Murray, Richard W. and Kallmeyer, Jens}, title = {Hydrogen Utilization Potential in Subsurface Sediments}, series = {Frontiers in microbiology}, volume = {7}, journal = {Frontiers in microbiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-302X}, doi = {10.3389/fmicb.2016.00008}, pages = {16}, year = {2016}, abstract = {Subsurface microbial communities undertake many terminal electron-accepting processes, often simultaneously. Using a tritium-based assay, we measured the potential hydrogen oxidation catalyzed by hydrogenase enzymes in several subsurface sedimentary environments (Lake Van, Barents Sea, Equatorial Pacific, and Gulf of Mexico) with different predominant electron-acceptors. Hydrogenases constitute a diverse family of enzymes expressed by microorganisms that utilize molecular hydrogen as a metabolic substrate, product, or intermediate. The assay reveals the potential for utilizing molecular hydrogen and allows qualitative detection of microbial activity irrespective of the predominant electron-accepting process. Because the method only requires samples frozen immediately after recovery, the assay can be used for identifying microbial activity in subsurface ecosystems without the need to preserve live material. We measured potential hydrogen oxidation rates in all samples from multiple depths at several sites that collectively span a wide range of environmental conditions and biogeochemical zones. Potential activity normalized to total cell abundance ranges over five orders of magnitude and varies, dependent upon the predominant terminal electron acceptor. Lowest per-cell potential rates characterize the zone of nitrate reduction and highest per-cell potential rates occur in the methanogenic zone. Possible reasons for this relationship to predominant electron acceptor include (i) increasing importance of fermentation in successively deeper biogeochemical zones and (ii) adaptation of H(2)ases to successively higher concentrations of H-2 in successively deeper zones.}, language = {en} } @article{AdhikariKallmeyer2010, author = {Adhikari, Rishi Ram and Kallmeyer, Jens}, title = {Detection and quantification of microbial activity in the subsurface}, issn = {0009-2819}, doi = {10.1016/j.chemer.2010.05.003}, year = {2010}, abstract = {The subsurface harbors a large fraction of Earth's living biomass, forming complex microbial ecosystems. Without a profound knowledge of the ongoing biologically mediated processes and their reaction to anthropogenic changes it is difficult to assess the long-term stability and feasibility of any type of geotechnical utilization, as these influence subsurface ecosystems. Despite recent advances in many areas of subsurface microbiology, the direct quantification of turnover processes is still in its infancy, mainly due to the extremely low cell abundances. We provide an overview of the currently available techniques for the quantification of microbial turnover processes and discuss their specific strengths and limitations. Most techniques employed so far have focused on specific processes, e.g. sulfate reduction or methanogenesis. Recent studies show that processes that were previously thought to exclude each other can occur simultaneously, albeit at very low rates. Without the identification of the respective processes it is impossible to quantify total microbial activity. Even in cases where all simultaneously occurring processes can be identified, the typically very low rates prevent quantification. In many cases a simple measure of total microbial activity would be a better and more robust measure than assays for several specific processes. Enzyme or molecular assays provide a more general approach as they target key metabolic compounds. Depending on the compound targeted a broader spectrum of microbial processes can be quantified. The two most promising compounds are ATP and hydrogenase, as both are ubiquitous in microbes. Technical constraints limit the applicability of currently available ATP-assays for subsurface samples. A recently developed hydrogenase radiotracer assay has the potential to become a key tool for the quantification of subsurface microbial activity.}, language = {en} } @article{AertsBotzenClarkeetal.2018, author = {Aerts, J. C. J. H. and Botzen, W. J. Wouter and Clarke, K. C. and Cutter, S. L. and Hall, J. W. and Merz, Bruno and Michel-Kerjan, E. and Mysiak, J. and Surminski, Swenja and Kunreuther, H.}, title = {Integrating human behaviour dynamics into flood disaster risk assessment}, series = {Nature climate change}, volume = {8}, journal = {Nature climate change}, number = {3}, publisher = {Nature Publ. Group}, address = {London}, issn = {1758-678X}, doi = {10.1038/s41558-018-0085-1}, pages = {193 -- 199}, year = {2018}, abstract = {The behaviour of individuals, businesses, and government entities before, during, and immediately after a disaster can dramatically affect the impact and recovery time. However, existing risk-assessment methods rarely include this critical factor. In this Perspective, we show why this is a concern, and demonstrate that although initial efforts have inevitably represented human behaviour in limited terms, innovations in flood-risk assessment that integrate societal behaviour and behavioural adaptation dynamics into such quantifications may lead to more accurate characterization of risks and improved assessment of the effectiveness of risk-management strategies and investments. Such multidisciplinary approaches can inform flood-risk management policy development.}, language = {en} } @article{AgadaChenGeigeretal.2014, author = {Agada, S. and Chen, F. and Geiger, S. and Toigulova, G. and Agar, Susan M. and Shekhar, R. and Benson, Gregory S. and Hehmeyer, O. and Amour, Fr{\´e}d{\´e}ric and Mutti, Maria and Christ, Nicolas and Immenhauser, A.}, title = {Numerical simulation of fluid-flow processes in a 3D high-resolution carbonate reservoir analogue}, series = {Petroleum geoscience}, volume = {20}, journal = {Petroleum geoscience}, number = {1}, publisher = {Geological Soc. Publ. House}, address = {Bath}, issn = {1354-0793}, doi = {10.1144/petgeo2012-096}, pages = {125 -- 142}, year = {2014}, abstract = {A high-resolution three-dimensional (3D) outcrop model of a Jurassic carbonate ramp was used in order to perform a series of detailed and systematic flow simulations. The aim of this study was to test the impact of small- and large-scale geological features on reservoir performance and oil recovery. The digital outcrop model contains a wide range of sedimentological, diagenetic and structural features, including discontinuity surfaces, shoal bodies, mud mounds, oyster bioherms and fractures. Flow simulations are performed for numerical well testing and secondary oil recovery. Numerical well testing enables synthetic but systematic pressure responses to be generated for different geological features observed in the outcrops. This allows us to assess and rank the relative impact of specific geological features on reservoir performance. The outcome documents that, owing to the realistic representation of matrix heterogeneity, most diagenetic and structural features cannot be linked to a unique pressure signature. Instead, reservoir performance is controlled by subseismic faults and oyster bioherms acting as thief zones. Numerical simulations of secondary recovery processes reveal strong channelling of fluid flow into high-permeability layers as the primary control for oil recovery. However, appropriate reservoir-engineering solutions, such as optimizing well placement and injection fluid, can reduce channelling and increase oil recovery.}, language = {en} }