Details of the abstract
Title of paper |
Multidimensional inversion of transient electromagnetic data for the exploration of clay pans in the Atacama Desert, Chile |
List of authors | Blanco-Arrué, B., Yogeshwar, P., Tezkan, B., Liu, Y., Peng, R., Wennrich, V. |
Affiliation(s) |
University of Cologne, Institute of Geophysics and Meteorology, Pohligstrasse 3, 50969 Cologne, Germany, University of Cologne, Institute of Geophysics and Meteorology, Pohligstrasse 3, 50969 Cologne, Germany, University of Cologne, Institute of Geophysics and Meteorology, Pohligstrasse 3, 50969 Cologne, Germany, University of Geosciences, Institute of Geophysics and Geomatics, 430074 Wuhan, China. University of Geosciences, Institute of Geophysics and Geomatics, 430074 Wuhan, China. University of Cologne, Institute of Geology and Mineralogy, Zülpicher Str.49a, 50674 Cologne, Germany, |
Summary | We present a geoscientific study to investigate clastic sediment successions of clay pans located in the hyperarid and arid core of the Atacama Desert along the Chilean Coastal Cordillera. The loop source transient electromagnetic method was performed to provide the sedimentary architecture and bedrock topography of selected clay pans through multidimensional inversion. A total of 116 soundings were carried out on a 3D grid in the Paranal clay pan during December 2019. The TEM-1D inversion results reveal a three-layered resistivity structure with reliable information down to a depth of 250 m. Colluvial and fluvial sediments reach a maximum thickness of about 160 ± 10 m. Additionally, a recent coring/drilling campaign confirmed our modeling results with an exceptional agreement (172 m depth). In order to avoid misinterpretations of TEM data due to multidimensional effects within the 1D models, a 2D inversion using the recently developed TEM3DInv code is performed. The 2D inversion of the TEM data derives a more accurate geometry of the clay pan with a basement of around ~160 m depth, and a good fit of the data is observed. The 2D or even 3D inversion of the entire TEM data set resolves the clay pan's complex geometry, giving an unbiased and independent interpretation. |
Session Keyword | 3.0 Exploration, Monitoring and Hazards |
File upload |
3.0_multidimensional_inversio_blanco.pdf
|