Fallas de salto en dirección en el basamento de la cuenca de antepaís del Guadalquivir

  1. V. Tendero-Salmerón 1
  2. J. Galindo-Zaldívar 1
  3. J.A. Peláez 2
  4. M. Martínez-Martos 3
  5. J. Henares 2
  6. C. Marín-Lechado 4
  7. A.J. Gil-Cruz 2
  8. A.C. López-Garrido 1
  1. 1 Instituto Andaluz de Ciencias de la Tierra
    info

    Instituto Andaluz de Ciencias de la Tierra

    Granada, España

    ROR https://ror.org/00v0g9w49

  2. 2 Universidad de Jaén
    info

    Universidad de Jaén

    Jaén, España

    ROR https://ror.org/0122p5f64

  3. 3 Universidad de Granada
    info

    Universidad de Granada

    Granada, España

    ROR https://ror.org/04njjy449

  4. 4 Instituto Geológico y Minero de España
    info

    Instituto Geológico y Minero de España

    Madrid, España

    ROR https://ror.org/04cadha73

Journal:
Geotemas (Madrid)

ISSN: 1576-5172

Year of publication: 2021

Issue Title: X Congreso Geológico de España

Issue: 18

Pages: 854

Type: Article

More publications in: Geotemas (Madrid)

Abstract

Several seismic swarms have affected the Eastern Guadalquivir Basin, located into the basement, which should be non-defor- med as the foreland of the Betic Cordillera. The most recent of them (2016-2018) is in the Guadiana Menor Valley, reaching a m bLg 4.1 event. Focal mechanisms are strike-slip solutions, and seismicity is distributed in a N-S elongated cluster. In addition to seismic analysis, other studies including surface researches, electric resistivity tomographies (ERT) and gra- vity prospecting have been carried out. Signs of active tectonics are scarce, but there are minor N-S vertical faults over the shallowest earthquakes (northern part of the cluster). ERT evidences the continuity of these faults. On the other hand, gravity anomaly models show a sedimentary infill that increases its thickness eastwards, in coherence with a foreland basin. Basement surface does not present big steps, scarps nor structures. Altogether supports that the origin of the seismicity is a NNE-SSW sinistral fault nucleated in the Iberian basement that may be propagating upwards. At regional scale, the generation of this fault has significant implications: this fault is not coherent with a strain partitioning or transfer fault models because of the absence of the geometry of the fault system. We propose a model of an incipient tecto- nic indentation in the Iberian basement, similar to the Palomares fault, associated to the Aguilas Arc.