Gathering different marine geology data (seismics, acoustics, sedimentological) to investigate active fluid seepage (AFS) in the southern region of the central Mediterranean Sea

Abstract

Active Fluid Seepage (AFS) at the seafloor is a global phenomenon associated with seafloor morphologies in different geodynamic contexts. Advances geophysical techniques have allowed geoscientists to characterise pockmarks, mounds and flares associated with AFS. We present a range of marine geological data acquired in the central Mediterranean Sea (northern Sicily continental margin, northwestern Sicily Channel and offshore the Maltese Islands), which allow us to identify AFSs. The AFSs are spatially distributed as clusters, aligned or isolated at different depths, ranging from few decametres offshore the Maltese Islands, up to 400 m offshore north Sicily and in the northwestern Sicily channel. Mounds have heights ranging from 2 to 15 m and form hummocky surfaces. Pockmarks with sub-circular planform shapes and U/V-shaped cross-sections are found in sizes ranging from 5 to 530 m. Gas flares occur on both the continental shelf and upper slope.