EGU21-12653, updated on 04 Mar 2021
https://doi.org/10.5194/egusphere-egu21-12653
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

36Cl exposure dating of post-glacial features along the Mt Vettore Fault (Central Apennines, Italy) constraining fault slip rate and last glacial advance.

Lea Pousse-Beltran1,3, Lucilla Benedetti1, Jules Fleury1, Paolo Boncio2, Valery Guillou1, Bruno Pace2, Magali Rizza1, Irene Puliti2, and Aster Team1
Lea Pousse-Beltran et al.
  • 1Aix Marseille Univ, CNRS, IRD, Coll France, CEREGE, Aix-en-Provence, France
  • 2University “G. d'Annunzio”, Chieti-Pescara, Italy
  • 3School of Earth and Ocean Sciences, University of Victoria, Victoria, British Columbia, Canada

In the Central Apennines (Italy), up to now, no absolute dating directly based on the moraines has been carried out to constrain glacial oscillation. However, climatic constrains are often used in the Central Apennine to estimate long term (> 10 ka) fault slip rate. In addition slip rate assessments based on offset morphotectonic markers on the main branches of fault systems and encompassing several seismic cycles (> 10 ka) are sparse. This is particularly true for the Monte Vettore-Monte Bove fault system which triggered the 2016-2017 seismic sequence. We thus provide new assessment for the vertical slip rates along the Mt Vettore-Mt Bove fault system.  Offset measurements were made using a 5-cm resolution DEM obtained through a drone survey and constrain a fault scarp height of 15.5 ± 1.4 m and a cumulative offset of 32-40.5 m. Samples were collected from the Valle Lunga terminal moraine at 1710 m asl and yield 36Cl exposure ages of 12.7 + 2.2/-1.9 ka while the flat, abraded surface located on top of the tectonic scarp yield 36Cl exposure ages of 23.4 + 5.3/-4.3 ka. Assuming the offset started to accumulate when climate conditions allow its preservation, thus once the surface was abandoned, we constrain a vertical slip rate of 1.2 ± 0.2 mm/yr along the master branch of the Mt Vettore normal fault.  This rate is higher than the ones previously obtained from trenches along secondary splays of the Mt Vettore-Mt Bove and on the Norcia fault systems. Besides, the yielded chronology for the last glacial maximum in that area at ~23 ka is in good agreement with the timing previously proposed for the LGM in the Apennines.

How to cite: Pousse-Beltran, L., Benedetti, L., Fleury, J., Boncio, P., Guillou, V., Pace, B., Rizza, M., Puliti, I., and Team, A.: 36Cl exposure dating of post-glacial features along the Mt Vettore Fault (Central Apennines, Italy) constraining fault slip rate and last glacial advance., EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-12653, https://doi.org/10.5194/egusphere-egu21-12653, 2021.

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