000K utf8 1100 $c2004 1500 eng 2050 urn:nbn:de:gbv:8-diss-11382 3000 Leythaeuser, Thomas 4000 Origin and nature of the regional detachment fault in the area of the deep Galicia margin$hChristian-Albrechts-Universität zu Kiel [Leythaeuser, Thomas] 4030 Kiel$nChristian-Albrechts-Universität zu Kiel 4209 In the area of the Deep Galicia Margin two multi-channel seismic lines (ISE-1 and ISE-2) have been processed and interpreted in the present study. The main objective was to attempt clarification of the precise nature and origin of the so-called S-reflector. For this purpose a full waveform inversion was carried out for a selected CMP gather besides prestack depth migration and poststack time migration. The results of the full waveform inversion lead to the conclusion that the S-reflector represents an approx. 50m thick low-velocity zone wedged in a stepwise velocity increase between continental crust and mantle. For this zone a compressional wave velocity of 5.2 km/s was determined as compared to 5.45 km/s for the overlying continental crust and 7.0 km/s for the mantle interval below. These p-wave velocities in the uppermost mantle are interpreted to result from a particular serpentinisation history involving two separate stages of seawater influx leading to the development of a detachment fault seismically imaged as the S-reflector. 4950 https://nbn-resolving.org/urn:nbn:de:gbv:8-diss-11382$xR$3Volltext$534 4961 https://macau.uni-kiel.de/receive/diss_mods_00001138 5051 550 5550 Common-mid-point-Refraktionsseismik 5550 detachment fault 5550 full waveform inversion 5550 Geophysik 5550 Iberische Halbinsel <West> 5550 Kontinentalrand 5550 passive continental margin 5550 peridotite ridge 5550 rifting 5550 Rifting 5550 serpentinisation 5550 Spanien 5550 S-reflector