Rudersdorf, A et al. (2013): Ground penetrating radar (GPR) and electrical resistivity tomography (ERT) survey on the neotectonic activity of the Padul-Nigüelas Fault Zone (PNFZ), Southern Spain. doi:10.1594/PANGAEA.806520, Supplement to:Rudersdorf, Andreas; Hürtgen, Jochen; Grützner, Christoph; Reicherter, Klaus (2011): Neotectonic activity of the Granada Basin - new evidence from the Padul-Nigüelas Fault Zone. In: C. Grützner, R. Pérez-López, T. Fernández-Steeger, I. Papanikolaou, K. Reicherter, P.G. Silva & A. Vött, (Eds.): Earthquake Geology and Archaeology: Science, Society and Critical facilities. ISBN 978-960-466-093-3, 2nd INQUA-IGCP-567 International Workshop on Active Tectonics, Earthquake Geology, Archaeology and Engineering, Corinth, Greece, 214-217, hdl:10013/epic.40770.d024
The Padul-Nigüelas Fault Zone (PNFZ) is situated at the south-western mountain front of the Sierra Nevada (Spain) in an extensive regime and belongs to the internal zone of the Betic Cordilleras. The aim of this study is a collection of new evidence for neotectonic activity of the fault zone with classical geological field work and modern geophysical methods, such as ground penetrating radar (GPR). Among an apparently existing bed rock fault scarp with triangular facets, other evidences, such as deeply incised valleys and faults in the colluvial wedges, are present in the PNFZ. The preliminary results of our recent field work have shown that the synsedimentary faults within the colluvial sediments seem to propagate basinwards and the bed rock fault is only exhumed due to erosion for the studied segment (west of Marchena). We will use further GPR data and geomorphologic indices to gather further evidences of neotectonic activity of the PNFZ.
During a field work campaign in April 2011 we gathered several GPR (ground penetrating radar) and ERT (electrical resistivity tomography) profiles in the area around Padul and Nigüelas (Granada Basin, Southern Spain). We focused on the Padul-Nigüelas Fault Zone (PNFZ), which is located at the south-western border of the Sierra Nevada mountain range. It is a segmented fault zone built up by normal faults dipping towards SW.
GPS: Coordinates of Surveys / Photos
The coordinates for the survey profiles (GPR and ERT) and for the field photographs are provided in the KMZ-file (GPS_PNFZ_Pangea.kmz)
GPR: Ground Penetrating Radar
We used a GPR system from "Geophysical Survey Systems INC" (GSSI) with a control unit (GSSI SIR-3000), a monostatic antenna (GSSI Model 5104A), working at a centre frequency of 270 MHz, a survey wheel for recording the distance and a GPS tracker for locating the profile track.
Processing of the GPR data was done with ReflexW (Version 6.0.5 by Sandmeier Scientific Software). Coordinates of the start and end points and the tracks of the GPR profiles are provided in the KMZ-file (GPS_PNFZ.kmz). Weather conditions were sunny and dry during the field work.
ERT: Electrical Resistivity Tomography
The data was acquired by using a 4Point Light measuring device from "Lippmann Geophysikalische Messgeräte" in a dipole-dipole configuration. We used 80 electrodes with a spacing of 50 cm, resulting in a profile length of 39.5 m.
We have performed only one measurement due to bad underground conditions in the study area (very dry and solid ground). The profile was done parallel to the GPR profile 96 (Electrical_Survey_parallelGPR096_interpretation.pdf)
- raw data of ERT profile (Electrical_Survey_parallelGPR096_Raw_data.dat)
- processed data of ERT profile (Electrical_Survey_parallelGPR096_Proc_data.dat)
- interpreted ERT profile and correlation to GPR profile 96 (Electrical_Survey_parallelGPR096_interpretation.pdf)
The processing of measured data was done with a demo version of RES2DINV from Geotomo Software. Coordinates of the start and end point of the ERT profile are provided in the KMZ-file (GPS_PNFZ.kmz).