Geological, geophysical and geotechnical highlights of the southern part of the Al Idrissi strike-slip fault system from the Alboran sea
- 1Sorbonne Université, CNRS-INSU, UMR 7193, Institut des Sciences de la Terre Paris, ISTeP, F-75005 Paris, France
- *A full list of authors appears at the end of the abstract
In the Alboran Sea, oblique convergence between the African and Eurasian plates led to the establishment of the Al Idrissi sinistral strike-slip fault system, initiating a new plate boundary, 1 Ma ago. Several moderate magnitude earthquakes (Mw > 6) have been recorded on different segments of this fault system. The objective of this study is to analyse the dynamics of this plate boundary by studying the tectonic activity and physical properties of the sedimentary series along a key transect of the fault system. To do so, we used a panel of geological, geophysical and geotechnical tools, some of which were acquired during the ALBACORE oceanographic campaign (R/V Pourquoi Pas? 2021).
The data analysed are derived from (i) sediment cores of the ALBACORE oceanographic cruise (with multi-sensor core logger - MSCL), (ii) heat flux measurements, (iii) penetration tests with the Ifremer Penfeld piezocone (CPTU) as well as (iv) multibeam bathymetry data and (v) seismic reflection/depth data. These data were acquired along a transect of the Bokkoya fault system, south of the Al Idrissi fault system. The length of the sedimentary series investigated allows the dating of major sedimentary events that occurred during the late Pleistocene and Holocene. Along this segment, isotope analysis of the carbonate biogenic components provided a 𝛿18O evolution curve that was converted into time series. Thus, a chronostratigraphic framework up to 80 ky could be constrained as well as variations in sedimentation rate between compartments on either side of the fault. The analysis of physical properties using heat flow, CPTU and MSCL data allows a detailed lithological and geophysical stratigraphy to be established along the transect and highlights the variability of geological, geotechnical and geophysical signatures on either side of the fault system. This work is part of the ANR ALBANEO project, which aims to understand the dynamics of this new plate boundary and, in the longer term, to assess the hazards in this area of the western Mediterranean Sea.
Gorini C.; Alonso B.; Le Roy P.; Benmarha O.; Besso R. ; Campderros S.; Corbera G.; Dano A. ; De la Fuente M.; Duval A-M.; Emmanuel L. ; Estrada F. ; Frigola J.; Latni E. M.; Lopez-Gonzalez N.; Medina Ketzer M.; Oliveira de Sa A.; Palomino D. ; Praeg D. ; Scalabrino B. ; Sheremet Y. ; Tenderon Salmeron V.; Ercilla G.,; Vazquez J.T. ; Migeon S. ; Ammar A.; Benmakhlouf M. ; El Moumni B. Brouillet JF, Le Callonnec L., Poort J., Cubas N., Thomas M., Migeon S., Ratzov G., Souloumiac P., Chamot-Rooke N., Casas D., Galindo-Zaldivar J.,
How to cite: Vidil, L., d'Acremont, E., Leroy, S., Lafuerza, S., Emmanuel, L., and Rabaute, A. and the ALBACORE and ALBANEO teams: Geological, geophysical and geotechnical highlights of the southern part of the Al Idrissi strike-slip fault system from the Alboran sea, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-6872, https://doi.org/10.5194/egusphere-egu23-6872, 2023.
