of Gibraltar and around the Carchuna Canyon (e.g. the Motril Canyon head) (Alonso
and Ercilla 2003; Vázquez et al. 2015a).
Small-scale submarine valleys comprise prodeltaic channels and/or gullies,
documented in a few prodeltaic deposits along the Iberian shelf (Bárcenas et al.
2016), as well as a prodeltaic deposit located in Al-Hoceima Bay, on the African
shelf (Lafosse et al. 2018) (Fig. 6.5a, c, d). The gullies are straight and very
shallowly incised (Bárcenas et al. 2016). They initiate over the prodeltaic topsets
and generally extend over the foresets (Bárcenas et al. 2016; Lafosse et al. 2018),
although they may be restricted to the outer shelf, as occurred in the case of the
Guadalfeo River prodelta (Lobo et al. 2006).
Wave-cut terraces are represented by abrupt escarpments with high lateral continuity. They are particularly frequent on the westernmost shelf of the northern
margin at various bathymetric levels (Hernández-Molina et al. 1996).
6.5.1.3 Gravitational Features
These are mostly represented by scarce shallow-water slides, occurring at water
depths of more than 60 m (Bárcenas et al. 2016). The slides range from 38 to 1000 m
long and 56 to 629 m wide (Fig. 6.5a, e).
6.5.1.4 Anthropogenic Features
These include spherical mounds and straight lineations, usually found in proximity
to harbours due to dredge activities (Bárcenas et al. 2016) (Fig. 6.5a, f). Mounds with
reliefs of between 25 and 50 m are around 80 m long and up to 100 m wide. The
lineations that have been mapped between water depths of 25 and 47 m, are
420–850 m long and have average widths of 20 m.
6.5.2 Deep-Sea Features
These include features of varying genesis that may be grouped as tectonic, seamount,
fluid-flow, contourite, mass-movement, and biogenic features (Figs. 6.6 and 6.7).
6.5.2.1 Tectonic Features
The main tectonic structures influencing the seafloor morphology are folds and
faults. These affect mainly the central and eastern seafloor of the Alboran Sea
(Fig. 6.7).
Folds have a dominant ENE-WSW strike and are up to several kilometres in
length, with the most representative being the Alboran Ridge, Francesc Pagès and
6 Seafloor Morphology and Processes in the Alboran Sea
169
and Ercilla 2003; Vázquez et al. 2015a).
Small-scale submarine valleys comprise prodeltaic channels and/or gullies,
documented in a few prodeltaic deposits along the Iberian shelf (Bárcenas et al.
2016), as well as a prodeltaic deposit located in Al-Hoceima Bay, on the African
shelf (Lafosse et al. 2018) (Fig. 6.5a, c, d). The gullies are straight and very
shallowly incised (Bárcenas et al. 2016). They initiate over the prodeltaic topsets
and generally extend over the foresets (Bárcenas et al. 2016; Lafosse et al. 2018),
although they may be restricted to the outer shelf, as occurred in the case of the
Guadalfeo River prodelta (Lobo et al. 2006).
Wave-cut terraces are represented by abrupt escarpments with high lateral continuity. They are particularly frequent on the westernmost shelf of the northern
margin at various bathymetric levels (Hernández-Molina et al. 1996).
6.5.1.3 Gravitational Features
These are mostly represented by scarce shallow-water slides, occurring at water
depths of more than 60 m (Bárcenas et al. 2016). The slides range from 38 to 1000 m
long and 56 to 629 m wide (Fig. 6.5a, e).
6.5.1.4 Anthropogenic Features
These include spherical mounds and straight lineations, usually found in proximity
to harbours due to dredge activities (Bárcenas et al. 2016) (Fig. 6.5a, f). Mounds with
reliefs of between 25 and 50 m are around 80 m long and up to 100 m wide. The
lineations that have been mapped between water depths of 25 and 47 m, are
420–850 m long and have average widths of 20 m.
6.5.2 Deep-Sea Features
These include features of varying genesis that may be grouped as tectonic, seamount,
fluid-flow, contourite, mass-movement, and biogenic features (Figs. 6.6 and 6.7).
6.5.2.1 Tectonic Features
The main tectonic structures influencing the seafloor morphology are folds and
faults. These affect mainly the central and eastern seafloor of the Alboran Sea
(Fig. 6.7).
Folds have a dominant ENE-WSW strike and are up to several kilometres in
length, with the most representative being the Alboran Ridge, Francesc Pagès and
6 Seafloor Morphology and Processes in the Alboran Sea
169