%0 Journal Article %1 rietbrock_scherbaum:1999 %A Rietbrock, Andreas %A Scherbaum, Frank %C Institut fr Allgemeine und Angewandte Geophysik, Ludwig-Maximilians-Universitt Mnchen, Theresienstrasse 41, 80333 Mnchen, Germany %D 1999 %I Blackwell Publishing %J Geophysical Journal International %K geophysics seismology %N 1 %P 57--67 %R 10.1046/j.1365-246X.1999.00708.x %T Crustal scattering at the KTB from combined microearthquake and receiver analysis %U http://dx.doi.org/10.1046/j.1365-246X.1999.00708.x %V 136 %X In December of 1994 a fluid injection experiment which triggered several hundreds of microearthquakes was conducted at the KTB main borehole (Oberpfalz, Germany). These events were recorded with a temporal seismic network at the surface. Out of the complete data set, a cluster of five events recorded at four mini-arrays consisting of eight or nine stations was used to investigate the crustal scattering properties in the vicinity of the KTB. For this purpose, the `Double Beam Method' (DBM; Kr&\#252;ger et al. 1993 , 1995, 1996) and the `Double Beam Imaging Method' (Scherbaum, Kr&\#252;ger &\#38; Weber 1997) were extended to curved wave fronts to drop the restriction of plane-wave propagation. This technique is used for imaging the crustal scattering strength using earthquake clusters recorded at close-by mini-arrays. The results of the array analysis show that the composition of the P coda is mainly affected by the site location of the arrays. Near-surface and deeper crustal scattering contribute in a very complicated pattern. Furthermore, with the present data set it was possible to identify reflections from the top of the Erbendorf Body. This is a very pronounced arrival in most of the recorded traces. In one of the arrays its amplitudes are even greater than the direct P phases. Five to eight coherent phases could be identified by the mini-arrays. Using only these phases, synthetic P-coda traces were constructed, which only contain the coherent part of the observed wavefield. By subtracting the synthetic coherent wavefield from the original traces we achieve a variance reduction in the P coda of up to 37 per cent. This leads to the conclusion that a large amount of the P coda at the KTB can be modelled by a simple deterministic single-scattering model using a small number of individual scatterers.

@article{rietbrock_scherbaum:1999, abstract = {In December of 1994 a fluid injection experiment which triggered several hundreds of microearthquakes was conducted at the KTB main borehole (Oberpfalz, Germany). These events were recorded with a temporal seismic network at the surface. Out of the complete data set, a cluster of five events recorded at four mini-arrays consisting of eight or nine stations was used to investigate the crustal scattering properties in the vicinity of the KTB. For this purpose, the `Double Beam Method' (DBM; Kr\&\#252;ger et al. 1993 , 1995, 1996) and the `Double Beam Imaging Method' (Scherbaum, Kr\&\#252;ger \&\#38; Weber 1997) were extended to curved wave fronts to drop the restriction of plane-wave propagation. This technique is used for imaging the crustal scattering strength using earthquake clusters recorded at close-by mini-arrays. The results of the array analysis show that the composition of the P coda is mainly affected by the site location of the arrays. Near-surface and deeper crustal scattering contribute in a very complicated pattern. Furthermore, with the present data set it was possible to identify reflections from the top of the Erbendorf Body. This is a very pronounced arrival in most of the recorded traces. In one of the arrays its amplitudes are even greater than the direct P phases. Five to eight coherent phases could be identified by the mini-arrays. Using only these phases, synthetic P-coda traces were constructed, which only contain the coherent part of the observed wavefield. By subtracting the synthetic coherent wavefield from the original traces we achieve a variance reduction in the P coda of up to 37 per cent. This leads to the conclusion that a large amount of the P coda at the KTB can be modelled by a simple deterministic single-scattering model using a small number of individual scatterers.}, added-at = {2012-09-01T13:08:21.000+0200}, address = {Institut fr Allgemeine und Angewandte Geophysik, Ludwig-Maximilians-Universitt Mnchen, Theresienstrasse 41, 80333 Mnchen, Germany}, author = {Rietbrock, Andreas and Scherbaum, Frank}, biburl = {https://www.bibsonomy.org/bibtex/2f3fd5166e612e3d2c9ed38a5476d971c/nilsma}, doi = {10.1046/j.1365-246X.1999.00708.x}, interhash = {f3ff45ca165c95891ff69fd2ec652d4b}, intrahash = {f3fd5166e612e3d2c9ed38a5476d971c}, issn = {0956-540X}, journal = {Geophysical Journal International}, keywords = {geophysics seismology}, month = jan, number = 1, pages = {57--67}, publisher = {Blackwell Publishing}, timestamp = {2021-02-09T13:27:34.000+0100}, title = {Crustal scattering at the KTB from combined microearthquake and receiver analysis}, url = {http://dx.doi.org/10.1046/j.1365-246X.1999.00708.x}, volume = 136, year = 1999 }