Archaeoseismology and Palaeoseismology in the Alpine ... - Tierra

1 st INQUA‐IGCP‐567 International Workshop on Earthquake Archaeology and Palaeoseismology)
Fig. 3: Trench walls from Los Trances site where Quaternary sediments can be observed faulted up to the surface. A total of 4 events are
identified. Location of trenches in Fig. 2.
Offshore Carboneras Fault
The high‐resolution IMPULS multichannel seismic profiles
allows to identify up to 7 seismostratigraphic units above
the Messinian uncomformity (Fig. 4a,e,f).
The profiles show a great variability of structures along
the fault zone, in part due to the interaction between “en
echelon” traces: positive flower structures can be
observed at the shelf, southwards simple reverse faults
block the gullies draining from the shelf (Gràcia et al.,
2006) (Fig. 4e), and complex compresive structures
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appear at the southern segment like pressure ridges (Fig.
4f) slowly dimed towards the south and finally buried by
hemipelagic sediments.
TOPAS profiles show the shallowest geometries of the
fault and evidence recent activity by fault scarps and
displaced reflectors (Fig. 4b,c,d). Also towards the south,
sediments overlay the fault zone suggesting a decrease of
the fault activity. From existing sediment core analyses
from the Almería channel (Bozzano et al., accepted)
sedimentation rates are calculated and slip rates can be
Fig. 4: a) Bathymetric map of the study area south of the Almería margin and location of MCS profiles, TOPAS profiles and sediment cores
acquired during the marine surveys. b,c,d) TOPAS profiles showing the Carboneras Fault Zone and Late Quaternary sediments faulted up to
the surface. Sediment cores are located in each profile. e,f) High‐resolution multichannel seismic profiles with reflectors defining the
seismostratigraphic units at the Carboneras Fault Zone, units appear faulted up to the surface.