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  - 
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  - Weber, Michael H.
A1  - Abu-Ayyash, Khalil
A1  - Abueladas, Abdel-Rahman
A1  - Agnon, Amotz
A1  - Al-Amoush, H.
A1  - Babeyko, Andrey
A1  - Bartov, Yosef
A1  - Baumann, M.
A1  - Ben-Avraham, Zvi
A1  - Bock, Günter
A1  - Bribach, Jens
A1  - El-Kelani, R.
A1  - Forster, A.
A1  - Förster, Hans-Jürgen
A1  - Frieslander, U.
A1  - Garfunkel, Zvi
A1  - Grunewald, Steffen
A1  - Gotze, Hans-Jürgen
A1  - Haak, Volker
A1  - Haberland, Christian
A1  - Hassouneh, Mohammed
A1  - Helwig, S.
A1  - Hofstetter, Alfons
A1  - Jackel, K. H.
A1  - Kesten, Dagmar
A1  - Kind, Rainer
A1  - Maercklin, Nils
A1  - Mechie, James
A1  - Mohsen, Amjad
A1  - Neubauer, F. M.
A1  - Oberhänsli, Roland
A1  - Qabbani, I.
A1  - Ritter, O.
A1  - Rumpker, G.
A1  - Rybakov, M.
A1  - Ryberg, Trond
A1  - Scherbaum, Frank
A1  - Schmidt, J.
A1  - Schulze, A.
A1  - Sobolev, Stephan Vladimir
A1  - Stiller, M.
A1  - Th, 
T1  - The crustal structure of the Dead Sea Transform
N2  - To address one of the central questions of plate tectonics-How do large transform systems work and what are their typical features?-seismic investigations across the Dead Sea Transform (DST), the boundary between the African and Arabian plates in the Middle East, were conducted for the first time. A major component of these investigations was a combined reflection/ refraction survey across the territories of Palestine, Israel and Jordan. The main results of this study are: (1) The seismic basement is offset by 3-5 km under the DST, (2) The DST cuts through the entire crust, broadening in the lower crust, (3) Strong lower crustal reflectors are imaged only on one side of the DST, (4) The seismic velocity sections show a steady increase in the depth of the crust-mantle transition (Moho) from 26 km at the Mediterranean to 39 km under the Jordan highlands, with only a small but visible, asymmetric topography of the Moho under the DST. These observations can be linked to the left-lateral movement of 105 km of the two plates in the last 17 Myr, accompanied by strong deformation within a narrow zone cutting through the entire crust. Comparing the DST and the San Andreas Fault (SAF) system, a strong asymmetry in subhorizontal lower crustal reflectors and a deep reaching deformation zone both occur around the DST and the SAF. The fact that such lower crustal reflectors and deep deformation zones are observed in such different transform systems suggests that these structures are possibly fundamental features of large transform plate boundaries
Y1  - 2004
ER  -