Response: Commentary: Deformation Pattern of the Northern Sector of the Malta Escarpment (Offshore SE Sicily, Italy): Fault Dimension, Slip Prediction, and Seismotectonic Implications

Argnani (2021) provides a commentary (hereafter ARGN) on our paper titled: “Deformation Pattern
of the Northern Sector of the Malta Escarpment: Fault Dimension, Slip Prediction, and
Seismotectonic Implications,” which was published in the journal Frontiers in Earth Science in
January 2021 (Gambino et al., 2021, hereafter GAMB). Through the interpretation of eight new
seismic profiles (six of which are reported in Supplementary Figure S1 of GAMB) crossing the Malta
Escarpment, GAMB pointed to a better definition of the geometry of three active faults (F1, F2, F3)
and their seismic potential by employing slip tendency modeling and forward analysis. The results
suggest that F3 is prone to be reactivated under the achieved stress field and has the capacity of
generating M > 7 earthquakes. ARGN raises concerns about the higher resolution and less
penetration of the eight newly acquired high-resolution multichannel reflection seismic profiles
and the seismic-stratigraphic pattern proposed by GAMB. According to ARGN, “the seismic profiles
analyzed by GAMB belong to different sets and have very different seismic characters and resolution,
making seismic facies correlation pretty difficult, also because no tie lines are available. As a result,
stratigraphic correlations are highly speculative and the ensuing uncertainties undermine the timing
of the tectonic evolution envisaged by GAMB, as well as the age and rate of activity of tectonic
structures.” Furthermore, ARGN argues on the hypothesis of an early large-scale slope instability
affecting the area. Most of the statements of ARGN seem to be based on his available older
multichannel reflection seismic profiles, which have, indeed, a higher penetration but less resolution.
We also agree that high-resolution digital multichannel seismic profiles are not easily comparable
with low-resolution multichannel seismic lines, but we see the clear advantage of a state-of-the-art
technology to image the upper strata of sedimentary systems. The used system proved its robustness
in many different settings worldwide and has been successfully used for many pre-site surveys for
drilling campaigns for the IODP and ICDP. As a result, we rebut point-by-point ARGN’s comments
and stand by our model on the active deformation pattern and seismotectonics of the northern sector
of the Malta Escarpment.