1887

Abstract

Summary

This study reveals the importance of reprocessing vintage seismic data, originally focused on deep targets, in order to retrieve near-surface velocity model and structure. This information can be verified and complemented using cost-effective geophysical methods (passive seismic and audio-magnetotelluric -AMT data technique). This methodology has been applied to the Empordà Neogene basin (NE of Spain) where oil reflection datasets are available. 41 H/V stations were deployed along one seismic reflection profile to detect seismic impedance contrast between Quaternary/Neogene sediments and basement (Palaeozoic and Mesozoic). In order to calculate this contrast depth, shear-wave velocity profile has been obtained using seismic noise array technique. The final model obtained from the different seismic datasets show a basin shape with a gentle dip at the SW end of profile and an abrupt dip at the NE side interpreted as the Roses Fault. Bedrock depth reaches 660 m at the center of the profile according to H/V results. Finally, an AMT survey was undertaken at 10 sites to report a detailed 2D geoelectrical image across the Roses fault. The electrical resistivity model allows to characterize both structure and fluid properties associated with fractures network within the fault.

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/content/papers/10.3997/2214-4609.20141977
2014-09-08
2020-06-02
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