Dalías (longitudes between À3
and À3.5
), with the Balanegra Fault being one of
the most significant, and which determine the location of the coastline (GalindoZaldívar et al. 2013) (Figs. 6.1b and 6.7). The sinistral Serrata-Carboneras Fault has
been identified south of Campo de Dalías, and its straight trace is characterized by
push-up ridges and sharp scarps on the seafloor (Vázquez et al. 2016). This sinistral
fault extends 80 km offshore towards Cape Gata (Figs. 6.1b and 6.7) and is one of
the main faults affecting the northeastern Alboran Sea although its present-day
activity is still under discussion (Moreno et al. 2016; Estrada et al. 2018).
6.5.2.2 Seamounts
The Alboran Sea is characterised by the presence of several highs scattered along the
continental margin and basins (Figs. 6.3b and 6.6) (Würtz and Rovere 2015). They
have different origins and sizes related to the complex geodynamic evolution of the
Alboran Sea (e.g. Palomino et al. 2015; Vázquez et al. 2015b). Seamounts mostly
consist of a series of folds of Miocene to Quaternary units (almost all represented by
the Xauen Bank, Frances Pagès Seamount, and the Alboran Ridge) and/or volcanic
bodies (e.g. Ammar et al. 2007; Martinez-Garcia et al. 2013; Vázquez et al. 2015b;
Estrada et al. 2018; Galindo-Zaldívar et al. 2018) (Fig. 6.8). They are hundreds of
metres high (400–1750 m), with the Alboran Ridge—located in the central sector—
being the major elevation that emerges locally, forming Alboran Island and crossing
the Alboran Sea obliquely with a NE-SW trend (Figs. 6.3b and 6.6a). The top of the
seamounts is relatively flat (in most of the shallowest ones, <300 m water depth) and
subrounded, and they usually present folded layers, structural ridges, and biogenic
features that favour the settling of benthic species associated with hard bottoms, like
cold water corals (Palomino et al. 2011). Indeed, these highs comprise heterogeneous habitat types and are considered hotspots for biodiversity. The seamount walls
have high-gradient slopes shaped by downslope features, like turbidite systems and
landslides (Fig. 6.6a). At their feet, seamounts are also characterised by along slope
features, such as contourite drifts and moats (Fig. 6.6).
6.5.2.3 Features Related to Fluid Outflow
Various fluid outflow related features in the Alboran Sea, including mud diapirs,
mud volcanoes, pockmarks, and authigenic carbonates, have been mapped in the
Alboran Sea (Figs. 6.6a and 6.9) (e.g. Pérez-Belzuz et al. 1997; Somoza et al. 2012;
León et al. 2014; Palomino et al. 2016) mostly piercing contourite deposits. They
occur mainly in the western part of the Alboran Basin, mostly affecting the Ceuta
contourite Drift.
Diapirs are dome-shaped features that rupture the overlying mobile sediments,
which in the Alboran Sea are muddy in nature (Fig. 6.9a). Diapirs are mainly located
in the Western Alboran Basin (Pérez-Belzuz et al. 1997). Although most diapirs are
buried below the Pliocene-Quaternary sediments, a few produce a morphological
6 Seafloor Morphology and Processes in the Alboran Sea
173
and À3.5
), with the Balanegra Fault being one of
the most significant, and which determine the location of the coastline (GalindoZaldívar et al. 2013) (Figs. 6.1b and 6.7). The sinistral Serrata-Carboneras Fault has
been identified south of Campo de Dalías, and its straight trace is characterized by
push-up ridges and sharp scarps on the seafloor (Vázquez et al. 2016). This sinistral
fault extends 80 km offshore towards Cape Gata (Figs. 6.1b and 6.7) and is one of
the main faults affecting the northeastern Alboran Sea although its present-day
activity is still under discussion (Moreno et al. 2016; Estrada et al. 2018).
6.5.2.2 Seamounts
The Alboran Sea is characterised by the presence of several highs scattered along the
continental margin and basins (Figs. 6.3b and 6.6) (Würtz and Rovere 2015). They
have different origins and sizes related to the complex geodynamic evolution of the
Alboran Sea (e.g. Palomino et al. 2015; Vázquez et al. 2015b). Seamounts mostly
consist of a series of folds of Miocene to Quaternary units (almost all represented by
the Xauen Bank, Frances Pagès Seamount, and the Alboran Ridge) and/or volcanic
bodies (e.g. Ammar et al. 2007; Martinez-Garcia et al. 2013; Vázquez et al. 2015b;
Estrada et al. 2018; Galindo-Zaldívar et al. 2018) (Fig. 6.8). They are hundreds of
metres high (400–1750 m), with the Alboran Ridge—located in the central sector—
being the major elevation that emerges locally, forming Alboran Island and crossing
the Alboran Sea obliquely with a NE-SW trend (Figs. 6.3b and 6.6a). The top of the
seamounts is relatively flat (in most of the shallowest ones, <300 m water depth) and
subrounded, and they usually present folded layers, structural ridges, and biogenic
features that favour the settling of benthic species associated with hard bottoms, like
cold water corals (Palomino et al. 2011). Indeed, these highs comprise heterogeneous habitat types and are considered hotspots for biodiversity. The seamount walls
have high-gradient slopes shaped by downslope features, like turbidite systems and
landslides (Fig. 6.6a). At their feet, seamounts are also characterised by along slope
features, such as contourite drifts and moats (Fig. 6.6).
6.5.2.3 Features Related to Fluid Outflow
Various fluid outflow related features in the Alboran Sea, including mud diapirs,
mud volcanoes, pockmarks, and authigenic carbonates, have been mapped in the
Alboran Sea (Figs. 6.6a and 6.9) (e.g. Pérez-Belzuz et al. 1997; Somoza et al. 2012;
León et al. 2014; Palomino et al. 2016) mostly piercing contourite deposits. They
occur mainly in the western part of the Alboran Basin, mostly affecting the Ceuta
contourite Drift.
Diapirs are dome-shaped features that rupture the overlying mobile sediments,
which in the Alboran Sea are muddy in nature (Fig. 6.9a). Diapirs are mainly located
in the Western Alboran Basin (Pérez-Belzuz et al. 1997). Although most diapirs are
buried below the Pliocene-Quaternary sediments, a few produce a morphological
6 Seafloor Morphology and Processes in the Alboran Sea
173