The North Alfeo fault extends from the SE flank of Mount Etna, offshore Eastern Sicily 150 km to the SE. It is interpreted to be the primary surface expression of a lateral slab tear fault (a lithospheric scale fault which bounds the W edge of the subducting Ionian slab). Ultra high-resolution micro-bathymetric data (1m grid) were acquired during the FocusX1 and FocusX2 cruises by the ROV Victor and AUV idefX. These data image the fine structure of a dextral strike-slip fault, with transpressive ridges and narrow lozenge shaped pull apart basins. A network of N-S oriented normal faults are also observed throughout, most prominently on a triangular plateau, but also further south along the horse-tail termination of a NW-SE oriented splay of the Malta Escarpment. Analog modeling using granular materials tested a range of boundary conditions (layer thickness, pre-existing plateaus above the fault trace, an oblique fault with respect to a step in the morphology and layer thickness, 15° change in orientation of the fault orientation below the layer of granular material, etc.). Certain large-scale features observed in the natural example can be reproduced; e.g. - regularly spaced transpressive ridges with 30° oblique fault splays (clockwise with respect to the fault trace at depth) and an imbricated pop-up within a larger transpressive plateau. Other features, like the pervasive N-S oriented domino faults are not easily reproduced. Their characteristic spacing (about 150m) implies the presence of a shallow detachment for these structures, probably ≤1 km.
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