TY  - JOUR
A1  - Frank, Dorothe A.
A1  - Reichstein, Markus
A1  - Bahn, Michael
A1  - Thonicke, Kirsten
A1  - Frank, David
A1  - Mahecha, Miguel D.
A1  - Smith, Pete
A1  - Van der Velde, Marijn
A1  - Vicca, Sara
A1  - Babst, Flurin
A1  - Beer, Christian
A1  - Buchmann, Nina
A1  - Canadell, Josep G.
A1  - Ciais, Philippe
A1  - Cramer, Wolfgang
A1  - Ibrom, Andreas
A1  - Miglietta, Franco
A1  - Poulter, Ben
A1  - Rammig, Anja
A1  - Seneviratne, Sonia I.
A1  - Walz, Ariane
A1  - Wattenbach, Martin
A1  - Zavala, Miguel A.
A1  - Zscheischler, Jakob
T1  - Effects of climate extremes on the terrestrial carbon cycle: concepts, processes and potential future impacts
JF  - Global change biology
N2  - Extreme droughts, heat waves, frosts, precipitation, wind storms and other climate extremes may impact the structure, composition and functioning of terrestrial ecosystems, and thus carbon cycling and its feedbacks to the climate system. Yet, the interconnected avenues through which climate extremes drive ecological and physiological processes and alter the carbon balance are poorly understood. Here, we review the literature on carbon cycle relevant responses of ecosystems to extreme climatic events. Given that impacts of climate extremes are considered disturbances, we assume the respective general disturbance-induced mechanisms and processes to also operate in an extreme context. The paucity of well-defined studies currently renders a quantitative meta-analysis impossible, but permits us to develop a deductive framework for identifying the main mechanisms (and coupling thereof) through which climate extremes may act on the carbon cycle. We find that ecosystem responses can exceed the duration of the climate impacts via lagged effects on the carbon cycle. The expected regional impacts of future climate extremes will depend on changes in the probability and severity of their occurrence, on the compound effects and timing of different climate extremes, and on the vulnerability of each land-cover type modulated by management. Although processes and sensitivities differ among biomes, based on expert opinion, we expect forests to exhibit the largest net effect of extremes due to their large carbon pools and fluxes, potentially large indirect and lagged impacts, and long recovery time to regain previous stocks. At the global scale, we presume that droughts have the strongest and most widespread effects on terrestrial carbon cycling. Comparing impacts of climate extremes identified via remote sensing vs. ground-based observational case studies reveals that many regions in the (sub-)tropics are understudied. Hence, regional investigations are needed to allow a global upscaling of the impacts of climate extremes on global carbon-climate feedbacks.
KW  - carbon cycle
KW  - climate change
KW  - climate extremes
KW  - climate variability
KW  - disturbance
KW  - terrestrial ecosystems
Y1  - 2015
U6  - https://doi.org/10.1111/gcb.12916
SN  - 1354-1013
SN  - 1365-2486
VL  - 21
IS  - 8
SP  - 2861
EP  - 2880
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Trauth, Martin H.
A1  - Bergner, Andreas G. N.
A1  - Foerster, Verena
A1  - Junginger, Annett
A1  - Maslin, Mark A.
A1  - Schäbitz, Frank
T1  - Episodes of environmental stability versus instability in Late Cenozoic lake records of Eastern Africa
JF  - Journal of human evolution
N2  - Episodes of environmental stability and instability may be equally important for African hominin speciation, dispersal, and cultural innovation. Three examples of a change from stable to unstable environmental conditions are presented on three different time scales: (1) the Mid Holocene (MH) wet dry transition in the Chew Bahir basin (Southern Ethiopian Rift; between 11 ka and 4 ka), (2) the MIS 5-4 transition in the Naivasha basin (Central Kenya Rift; between 160 ka and 50 ka), and (3) the Early Mid Pleistocene Transition (EMPT) in the Olorgesailie basin (Southern Kenya Rift; between 1.25 Ma and 0.4 Ma). A probabilistic age modeling technique is used to determine the timing of these transitions, taking into account possible abrupt changes in the sedimentation rate including episodes of no deposition (hiatuses). Interestingly, the stable-unstable conditions identified in the three records are always associated with an orbitally-induced decrease of insolation: the descending portion of the 800 kyr cycle during the EMPT, declining eccentricity after the 115 ka maximum at the MIS 5-4 transition, and after similar to 10 ka. This observation contributes to an evidence-based discussion of the possible mechanisms causing the switching between environmental stability and instability in Eastern Africa at three different orbital time scales (10,000 to 1,000,000 years) during the Cenozoic. This in turn may lead to great insights into the environmental changes occurring at the same time as hominin speciation, brain expansion, dispersal out of Africa, and cultural innovations and may provide key evidence to build new hypotheses regarding the causes of early human evolution. (C) 2015 Elsevier Ltd. All rights reserved.
KW  - Paleoclimate
KW  - East Africa
KW  - Human evolution
KW  - Lakes
KW  - Sediments
Y1  - 2015
U6  - https://doi.org/10.1016/j.jhevol.2015.03.011
SN  - 0047-2484
VL  - 87
SP  - 21
EP  - 31
PB  - Elsevier
CY  - London
ER  - 
TY  - JOUR
A1  - Musson, R. M. W.
A1  - Toro, G. R.
A1  - Coppersmith, Kevin J.
A1  - Bommer, Julian J.
A1  - Deichmann, N.
A1  - Bungum, Hilmar
A1  - Cotton, Fabrice Pierre
A1  - Scherbaum, Frank
A1  - Slejko, Dario
A1  - Abrahamson, Norman A.
T1  - Evaluating hazard results for Switzerland and how not to do it : a discussion of "Problems in the application of the SSHAC probability method for assessing earthquake hazards at Swiss nuclear power plants" by J-U Klugel
N2  - The PEGASOS project was a major international seismic hazard study, one of the largest ever conducted anywhere in the world, to assess seismic hazard at four nuclear power plant sites in Switzerland. Before the report of this project has become publicly available, a paper attacking both methodology and results has appeared. Since the general scientific readership may have difficulty in assessing this attack in the absence of the report being attacked, we supply a response in the present paper. The bulk of the attack, besides some misconceived arguments about the role of uncertainties in seismic hazard analysis, is carried by some exercises that purport to be validation exercises. In practice, they are no such thing; they are merely independent sets of hazard calculations based on varying assumptions and procedures, often rather questionable, which come up with various different answers which have no particular significance. (C) 2005 Elsevier B.V. All rights reserved
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Brown, Maxwell C.
A1  - Donadini, Fabio
A1  - Nilsson, Andreas
A1  - Panovska, Sanja
A1  - Frank, Ute
A1  - Korhonen, Kimmo
A1  - Schuberth, Maximilian
A1  - Korte, Monika
A1  - Constable, Catherine G.
T1  - GEOMAGIA50.v3: 2. A new paleomagnetic database for lake and marine sediments
JF  - Earth, planets and space
N2  - Background: GEOMAGIA50.v3 for sediments is a comprehensive online database providing access to published paleomagnetic, rock magnetic, and chronological data obtained from lake and marine sediments deposited over the past 50 ka. Its objective is to catalogue data that will improve our understanding of changes in the geomagnetic field, physical environments, and climate.
 Findings: GEOMAGIA50.v3 for sediments builds upon the structure of the pre-existing GEOMAGIA50 database for magnetic data from archeological and volcanic materials. A strong emphasis has been placed on the storage of geochronological data, and it is the first magnetic archive that includes comprehensive radiocarbon age data from sediments. The database will be updated as new sediment data become available.
 Conclusions: The web-based interface for the sediment database is located at http://geomagia.gfz-potsdam.de/geomagiav3/SDquery.php. This paper is a companion to Brown et al. (Earth Planets Space doi:10.1186/s40623-015-0232-0,2015) and describes the data types, structure, and functionality of the sediment database.
KW  - Geomagnetism
KW  - Paleomagnetism
KW  - Sediment magnetism
KW  - Rock magnetism
KW  - Environmental magnetism
KW  - Database
KW  - GEOMAGIA50
Y1  - 2015
U6  - https://doi.org/10.1186/s40623-015-0233-z
SN  - 1880-5981
VL  - 67
PB  - Springer
CY  - Heidelberg
ER  - 
TY  - JOUR
A1  - Dengler, Jürgen
A1  - Wagner, Viktoria
A1  - Dembicz, Iwona
A1  - Garcia-Mijangos, Itziar
A1  - Naqinezhad, Alireza
A1  - Boch, Steffen
A1  - Chiarucci, Alessandro
A1  - Conradi, Timo
A1  - Filibeck, Goffredo
A1  - Guarino, Riccardo
A1  - Janisova, Monika
A1  - Steinbauer, Manuel J.
A1  - Acic, Svetlana
A1  - Acosta, Alicia T. R.
A1  - Akasaka, Munemitsu
A1  - Allers, Marc-Andre
A1  - Apostolova, Iva
A1  - Axmanova, Irena
A1  - Bakan, Branko
A1  - Baranova, Alina
A1  - Bardy-Durchhalter, Manfred
A1  - Bartha, Sandor
A1  - Baumann, Esther
A1  - Becker, Thomas
A1  - Becker, Ute
A1  - Belonovskaya, Elena
A1  - Bengtsson, Karin
A1  - Benito Alonso, Jose Luis
A1  - Berastegi, Asun
A1  - Bergamini, Ariel
A1  - Bonini, Ilaria
A1  - Bruun, Hans Henrik
A1  - Budzhak, Vasyl
A1  - Bueno, Alvaro
A1  - Antonio Campos, Juan
A1  - Cancellieri, Laura
A1  - Carboni, Marta
A1  - Chocarro, Cristina
A1  - Conti, Luisa
A1  - Czarniecka-Wiera, Marta
A1  - De Frenne, Pieter
A1  - Deak, Balazs
A1  - Didukh, Yakiv P.
A1  - Diekmann, Martin
A1  - Dolnik, Christian
A1  - Dupre, Cecilia
A1  - Ecker, Klaus
A1  - Ermakov, Nikolai
A1  - Erschbamer, Brigitta
A1  - Escudero, Adrian
A1  - Etayo, Javier
A1  - Fajmonova, Zuzana
A1  - Felde, Vivian A.
A1  - Fernandez Calzado, Maria Rosa
A1  - Finckh, Manfred
A1  - Fotiadis, Georgios
A1  - Fracchiolla, Mariano
A1  - Ganeva, Anna
A1  - Garcia-Magro, Daniel
A1  - Gavilan, Rosario G.
A1  - Germany, Markus
A1  - Giladi, Itamar
A1  - Gillet, Francois
A1  - Giusso del Galdo, Gian Pietro
A1  - Gonzalez, Jose M.
A1  - Grytnes, John-Arvid
A1  - Hajek, Michal
A1  - Hajkova, Petra
A1  - Helm, Aveliina
A1  - Herrera, Mercedes
A1  - Hettenbergerova, Eva
A1  - Hobohm, Carsten
A1  - Huellbusch, Elisabeth M.
A1  - Ingerpuu, Nele
A1  - Jandt, Ute
A1  - Jeltsch, Florian
A1  - Jensen, Kai
A1  - Jentsch, Anke
A1  - Jeschke, Michael
A1  - Jimenez-Alfaro, Borja
A1  - Kacki, Zygmunt
A1  - Kakinuma, Kaoru
A1  - Kapfer, Jutta
A1  - Kavgaci, Ali
A1  - Kelemen, Andras
A1  - Kiehl, Kathrin
A1  - Koyama, Asuka
A1  - Koyanagi, Tomoyo F.
A1  - Kozub, Lukasz
A1  - Kuzemko, Anna
A1  - Kyrkjeeide, Magni Olsen
A1  - Landi, Sara
A1  - Langer, Nancy
A1  - Lastrucci, Lorenzo
A1  - Lazzaro, Lorenzo
A1  - Lelli, Chiara
A1  - Leps, Jan
A1  - Loebel, Swantje
A1  - Luzuriaga, Arantzazu L.
A1  - Maccherini, Simona
A1  - Magnes, Martin
A1  - Malicki, Marek
A1  - Marceno, Corrado
A1  - Mardari, Constantin
A1  - Mauchamp, Leslie
A1  - May, Felix
A1  - Michelsen, Ottar
A1  - Mesa, Joaquin Molero
A1  - Molnar, Zsolt
A1  - Moysiyenko, Ivan Y.
A1  - Nakaga, Yuko K.
A1  - Natcheva, Rayna
A1  - Noroozi, Jalil
A1  - Pakeman, Robin J.
A1  - Palpurina, Salza
A1  - Partel, Meelis
A1  - Paetsch, Ricarda
A1  - Pauli, Harald
A1  - Pedashenko, Hristo
A1  - Peet, Robert K.
A1  - Pielech, Remigiusz
A1  - Pipenbaher, Natasa
A1  - Pirini, Chrisoula
A1  - Pleskova, Zuzana
A1  - Polyakova, Mariya A.
A1  - Prentice, Honor C.
A1  - Reinecke, Jennifer
A1  - Reitalu, Triin
A1  - Pilar Rodriguez-Rojo, Maria
A1  - Rolecek, Jan
A1  - Ronkin, Vladimir
A1  - Rosati, Leonardo
A1  - Rosen, Ejvind
A1  - Ruprecht, Eszter
A1  - Rusina, Solvita
A1  - Sabovljevic, Marko
A1  - Maria Sanchez, Ana
A1  - Savchenko, Galina
A1  - Schuhmacher, Oliver
A1  - Skornik, Sonja
A1  - Sperandii, Marta Gaia
A1  - Staniaszek-Kik, Monika
A1  - Stevanovic-Dajic, Zora
A1  - Stock, Marin
A1  - Suchrow, Sigrid
A1  - Sutcliffe, Laura M. E.
A1  - Swacha, Grzegorz
A1  - Sykes, Martin
A1  - Szabo, Anna
A1  - Talebi, Amir
A1  - Tanase, Catalin
A1  - Terzi, Massimo
A1  - Tolgyesi, Csaba
A1  - Torca, Marta
A1  - Torok, Peter
A1  - Tothmeresz, Bela
A1  - Tsarevskaya, Nadezda
A1  - Tsiripidis, Ioannis
A1  - Tzonev, Rossen
A1  - Ushimaru, Atushi
A1  - Valko, Orsolya
A1  - van der Maarel, Eddy
A1  - Vanneste, Thomas
A1  - Vashenyak, Iuliia
A1  - Vassilev, Kiril
A1  - Viciani, Daniele
A1  - Villar, Luis
A1  - Virtanen, Risto
A1  - Kosic, Ivana Vitasovic
A1  - Wang, Yun
A1  - Weiser, Frank
A1  - Went, Julia
A1  - Wesche, Karsten
A1  - White, Hannah
A1  - Winkler, Manuela
A1  - Zaniewski, Piotr T.
A1  - Zhang, Hui
A1  - Ziv, Yaron
A1  - Znamenskiy, Sergey
A1  - Biurrun, Idoia
T1  - GrassPlot - a database of multi-scale plant diversity in Palaearctic grasslands
JF  - Phytocoenologia
N2  - GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board.
KW  - biodiversity
KW  - European Vegetation Archive (EVA)
KW  - Eurasian Dry Grassland Group (EDGG)
KW  - grassland vegetation
KW  - GrassPlot
KW  - macroecology
KW  - multi-taxon
KW  - nested plot
KW  - scale-dependence
KW  - species-area relationship (SAR)
KW  - sPlot
KW  - vegetation-plot database
Y1  - 2018
U6  - https://doi.org/10.1127/phyto/2018/0267
SN  - 0340-269X
VL  - 48
IS  - 3
SP  - 331
EP  - 347
PB  - Cramer
CY  - Stuttgart
ER  - 
TY  - JOUR
A1  - Malischewsky, Peter G.
A1  - Scherbaum, Frank
T1  - Love's formula and H/V-ratio (ellipticity) of Rayleigh waves
N2  - The ellipticity of Rayleigh surface waves, which is an important parameter characterizing the propagation medium, is studied for several models with increasing complexity. While the main focus lies on theory, practical implications of the use of the horizontal to vertical component ratio (H/V-ratio) to Study the subsurface structure are considered as well. Love's approximation of the ellipticity for an incompressible layer over an incompressible half-space is critically discussed especially concerning its applicability for different impedance contrasts. The main result is an analytically exact formula of H/V for a 2-layer model of compressible media, which is a generalization of Love's formula. It turns out that for a limited range of models Love's approximation can be used also in the general case. (C) 2003 Elsevier B.V. All rights reserved
Y1  - 2004
SN  - 0165-2125
ER  - 
TY  - JOUR
A1  - Schmedes, J.
A1  - Hainzl, Sebastian
A1  - Reamer, S. K.
A1  - Scherbaum, Frank
A1  - Hinzen, K. G.
T1  - Moment release in the Lower Rhine Embayment, Germany : seismological perspective of the deformation process
N2  - An important task of seismic hazard assessment consists of estimating the rate of seismic moment release which is correlated to the rate of tectonic deformation and the seismic coupling. However, the estimations of deformation depend on the type of information utilized (e.g. geodetic, geological, seismic) and include large uncertainties. We therefore estimate the deformation rate in the Lower Rhine Embayment (LRE), Germany, using an integrated approach where the uncertainties have been systematically incorporated. On the basis of a new homogeneous earthquake catalogue we initially determine the frequency-magnitude distribution by statistical methods. In particular, we focus on an adequate estimation of the upper bound of the Gutenberg-Richter relation and demonstrate the importance of additional palaeoseis- mological information. The integration of seismological and geological information yields a probability distribution of the upper bound magnitude. Using this distribution together with the distribution of Gutenberg-Richter a and b values, we perform Monte Carlo simulations to derive the seismic moment release as a function of the observation time. The seismic moment release estimated from synthetic earthquake catalogues with short catalogue length is found to systematically underestimate the long-term moment rate which can be analytically determined. The moment release recorded in the LRE over the last 250 yr is found to be in good agreement with the probability distribution resulting from the Monte Carlo simulations. Furthermore, the long-term distribution is within its uncertainties consistent with the moment rate derived by geological measurements, indicating an almost complete seismic coupling in this region. By means of Kostrov's formula, we additionally calculate the full deformation rate tensor using the distribution of known focal mechanisms in LRE. Finally, we use the same approach to calculate the seismic moment and the deformation rate for two subsets of the catalogue corresponding to the east- and west-dipping faults, respectively
Y1  - 2005
SN  - 0956-540X
ER  - 
TY  - JOUR
A1  - Sirocko, Frank
A1  - Dietrich, Stephan
A1  - Veres, Daniel
A1  - Grootes, Pieter M.
A1  - Schaber-Mohr, Katja
A1  - Seelos, Klemens
A1  - Nadeau, Marie-Josee
A1  - Kromer, Bernd
A1  - Rothacker, Leo
A1  - Roehner, Marieke
A1  - Krbetschek, Matthias
A1  - Appleby, Peter G.
A1  - Hambach, Ulrich
A1  - Rolf, Christian
A1  - Sudo, Masafumi
A1  - Grim, Stephanie
T1  - Multi-proxy dating of Holocene maar lakes and Pleistocene dry maar sediments in the Eifel, Germany
JF  - Quaternary science reviews : the international multidisciplinary research and review journal
N2  - During the last twelve years the ELSA Project (Eifel Laminated Sediment Archive) at Mainz University has drilled a total of about 52 cores from 27 maar lakes and filled-in maar basins in the Eifel/Germany. Dating has been completed for the Holocene cores using 6 different methods (Pb-210 and Cs-137 activities, palynostratigraphy, event markers, varve counting, C-14) In general, the different methods consistently complement one another within error margins. Event correlation was used for relating typical lithological changes with historically known events such as the two major Holocene flood events at 1342 AD and ca 800 BC. Dating of MIS2-MIS3 core sections is based on greyscale tuning, radiocarbon and OSL dating, magnetostratigraphy and tephrochronology. The lithological changes in the sediment cores demonstrate a sequence of events similar to the North Atlantic rapid climate variability of the Last Glacial Cycle. The warmest of the MIS3 interstadials was GI14, when a forest with abundant spruce covered the Eifel area from 55 to 48 ka BP, i.e. during a time when also other climate archives in Europe suggested very warm conditions. The forest of this "Early Stage 3 warm phase" developed subsequently into a steppe with scattered birch and pine, and finally into a glacial desert at around 25 ka BP. Evidence for Mono Lake and Laschamp geomagnetic excursions is found in two long cores. Several large eruptions during Middle and Late Pleistocene (Ulmener Maar - 11,000 varve years BP, Laacher See - 12,900 varve years BP, Mosenberg volcanoes/Meerfelder Maar 41-45 cal ka BP, Dumpel Maar 116 ka BP, Glees Maar - 151 ka BP) produced distinct ash-layers crucial for inter-core and inter-site correlations. The oldest investigated maar of the Eifel is Ar-40/Ar-39 dated to the time older than 520 ka BP.
KW  - Eifel maar
KW  - Laminated lake sediments
KW  - Tuning
KW  - Historical events
KW  - C-14-derived chronology
KW  - Varve counting
KW  - Luminescence dating
KW  - Palynostratigraphy
KW  - (CS)-C-137 and Pb-210 dating
KW  - Palaeomagnetism
KW  - Tephrostratigraphy
KW  - Argon-Argon dating
KW  - GIS
Y1  - 2013
U6  - https://doi.org/10.1016/j.quascirev.2012.09.011
SN  - 0277-3791
VL  - 62
SP  - 56
EP  - 76
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Tran Thanh Tuan, 
A1  - Scherbaum, Frank
A1  - Malischewsky, Peter G.
T1  - On the relationship of peaks and troughs of the ellipticity (H/V) of Rayleigh waves and the transmission response of single layer over half-space models
JF  - Geophysical journal international
N2  - One of the key challenges in the context of local site effect studies is the determination of frequencies where the shakeability of the ground is enhanced. In this context, the H/V technique has become increasingly popular and peak frequencies of H/V spectral ratio are sometimes interpreted as resonance frequencies of the transmission response. In the present study, assuming that Rayleigh surface wave is dominant in H/V spectral ratio, we analyse theoretically under which conditions this may be justified and when not. We focus on 'layer over half-space' models which, although seemingly simple, capture many aspects of local site effects in real sedimentary structures. Our starting point is the ellipticity of Rayleigh waves. We use the exact formula of the H/V-ratio presented by Malischewsky & Scherbaum (2004) to investigate the main characteristics of peak and trough frequencies. We present a simple formula illustrating if and where H/V-ratio curves have sharp peaks in dependence of model parameters. In addition, we have constructed a map, which demonstrates the relation between the H/V-peak frequency and the peak frequency of the transmission response in the domain of the layer's Poisson ratio and the impedance contrast. Finally, we have derived maps showing the relationship between the H/V-peak and trough frequency and key parameters of the model such as impedance contrast. These maps are seen as diagnostic tools, which can help to guide the interpretation of H/V spectral ratio diagrams in the context of site effect studies.
KW  - Site effects
KW  - Theoretical seismology
KW  - Wave propagation
Y1  - 2011
U6  - https://doi.org/10.1111/j.1365-246X.2010.04863.x
SN  - 0956-540X
VL  - 184
IS  - 2
SP  - 793
EP  - 800
PB  - Wiley-Blackwell
CY  - Malden
ER  - 
TY  - JOUR
A1  - Hinzen, K. G.
A1  - Weber, B.
A1  - Scherbaum, Frank
T1  - On the resolution of H/V measurements to determine sediment thickness, a case study across a normal fault in the Lower Rhine Embayment, Germany
N2  - In recent years, H/V measurements have been increasingly used to map the thickness of sediment fill in sedimentary basins in the context of seismic hazard assessment. This parameter is believed to be an important proxy for the site effects in sedimentary basins (e.g. in the Los Angeles basin). Here we present the results of a test using this approach across an active normal fault in a structurally well known situation. Measurements on a 50 km long profile with 1 km station spacing clearly show a change in the frequency of the fundamental peak of H/V ratios with increasing thickness of the sediment layer in the eastern part of the Lower Rhine Embayment. Subsequently, a section of 10 km length across the Erft-Sprung system, a normal fault with ca. 750 m vertical offset, was measured with a station distance of 100 m. Frequencies of the first and second peaks and the first trough in the H/V spectra are used in a simple resonance model to estimate depths of the bedrock. While the frequency of the first peak shows a large scatter for sediment depths larger than ca. 500 m, the frequency of the first trough follows the changing thickness of the sediments across the fault. The lateral resolution is in the range of the station distance of 100 m. A power law for the depth dependence of the S-wave velocity derived from down hole measurements in an earlier study [Budny, 1984] and power laws inverted from dispersion analysis of micro array measurements [Scherbaum et al., 2002] agree with the results from the H/V ratios of this study
Y1  - 2004
SN  - 1363-2469
ER  -