Preliminary paleomagnetic survey of cretaceous dykes from Eastern Paraguay

  1. K. L. Kapper 1
  2. M. Calvo-Rathert 2
  3. R. Cejudo Ruiz 1
  4. L. Sanchez 3
  5. A. Irurzun 4
  6. A. Carrancho 2
  7. A. Gogichaishvili 1
  8. J. Morales 1
  9. A. Sinito 4
  1. 1 Universidad Nacional Autónoma de México
    info

    Universidad Nacional Autónoma de México

    Ciudad de México, México

    ROR https://ror.org/01tmp8f25

  2. 2 Universidad de Burgos
    info

    Universidad de Burgos

    Burgos, España

    ROR https://ror.org/049da5t36

  3. 3 Universidad de la República
    info

    Universidad de la República

    Montevideo, Uruguay

    ROR https://ror.org/030bbe882

  4. 4 Universidad Nacional del Centro de la Provincia de Buenos Aires
    info

    Universidad Nacional del Centro de la Provincia de Buenos Aires

    Tandil, Argentina

    ROR https://ror.org/011gakh74

Journal:
Latinmag Letters

ISSN: 2007-9656

Year of publication: 2016

Volume: 6

Issue: B17

Pages: 1-6

Type: Article

More publications in: Latinmag Letters

Abstract

We present preliminary rock magnetic results and paleodirections from a Cretaceous alkaline dyke swarmin the Asunción Rift, Eastern Paraguay. Previous investigations suggest that these dykes extruded in a rathershort period of time, in the period 126-127 Ma, during normal and reversed polarity field configuration(Velazquez et al., 2011). Paleodirectional results of alternating field and thermal demagnetization showedlinear vector diagrams, but also two components and erratic behavior. Six out of 22 sites have clustereddirections with a α95 ≤ 10.0°. Most of the accepted sites reveal inverse polarity, but we also observe reliablenormal and intermediate polarity sites. Rock magnetic experiments yield reversible thermomagnetic curveswith magnetite as carrier of remanence in 67% of the studied cases and samples characterized by pseudosingle-domain (PSD) behavior. The present preliminary study will be complemented with further rockmagnetic measurements, directional determinations and paleointensity experiments.