partially distorted due to renewed uplift of the structural highs produced by the postTortonian compressive deformation, especially in the central sector of the
Alboran Sea.
The main sedimentary basin formed on the strongly thinned crust of the Alboran
Domain corresponds to the WAB, which is also the deepest depression and reaches
8 s twtt at Morocco offshore and 7 s twt at Spain offshore (Figs. 5.4 and 5.10). It is
the thickest sedimentary depocenter in the Alboran Basin, estimated to lie at a depth
between 10 and 12 km (Soto et al. 1996, 2010; Mauffret et al. 2007; Iribarren et al.
2009; Do Couto et al. 2016). Its geometry in plain view is arched, its axis mimicking
the arcuate geometry of the orogenic arc, forming a curvilinear “bean” shape that
continues toward the north to a secondary E-W basin. The northern branch has a
NE-SW trend that changes to NNW-SSE southward, from latitude 36
N. This basin
is largely affected by shale tectonics (Soto et al. 2010, 2012) and associated mud
volcanism (Pérez-Belzuz et al. 1997; Sautkin et al. 2003; Talukder et al. 2003;
Blinova et al. 2011; Somoza et al. 2012; Gennari et al. 2013).
The Motril Basin has an E-W direction, arranged approximately parallel to the
northern coast of the Alboran Sea, with a slightly trapezoidal to elongated geometry,
and its maximum thickness is greater than 4 s twtt (Fig. 5.10). The basin lies in the
eastern extension of the northern branch of the WAB, just slightly disconnected from
it (Vázquez 2001). The Intermediate Basin has no influence on the current physiography of the Alboran Sea. It is situated between the La Herradura-Djibouti Ville
Banks and the DSDP highs (Fig. 5.10). Its geometry is oval, with a maximum axis of
trend NNW-SSE. The maximum sedimentary thickness (>3.5 s twtt) is found in its
northern part. This basin could be considered as an eastern secondary marginal
sub-basin related to the main WAB. In turn, the southern sector of the Intermediate
Basin would extend to the east along the Alboran Central Trough, of NE-SW
orientation, that has a maximum thickness greater than 3 s twtt and a corridor
geometry that is highly controlled by post-Tortonian compressive processes.
The continental crust described as belonging to the North Africa domain hosts
three sedimentary basins. The longest is the SAB, located between the southern flank
of the Alboran Ridge and the Trois Fourches Promontory (Vázquez 2001), having a
NE-SW direction and a slightly trapezoidal to elongated geometry. The maximum
thicknesses (>4 s twtt—Do Couto et al. 2016; locally ~4 km of sediments—
Martínez-García et al. 2017) are located in its southwestern sector (Fig. 5.10). The
formation of this basin and its current geometry are controlled by the post-Tortonian
compressive deformation. It is separated from the WAB owing to progressive
Alboran Ridge uplift since the upper Tortonian (Martínez-García et al. 2017) by
folding and thrusting northward (Estrada et al. 2018).
Two sedimentary basins have been described to the east of the SAB: the Pytheas
and Habibas basins. The Habibas basin (at least) is floored by continental metamorphic rocks (Medaouri et al. 2012, 2014). Both basins have an elongated geometry
trending NE-SW to ENE-WSW and have an expression on the seafloor at their
northern segment. The Habibas basin has a maximum thickness close to 4.5 s twtt
(Gómez de la Peña et al. 2018) and is bounded to the north by the Yusuf Fault
(Figs. 5.4 and 5.10), to the east by the Alidade Bank, and to the west by the E
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J.-T. Vázquez et al.
Alboran Sea.
The main sedimentary basin formed on the strongly thinned crust of the Alboran
Domain corresponds to the WAB, which is also the deepest depression and reaches
8 s twtt at Morocco offshore and 7 s twt at Spain offshore (Figs. 5.4 and 5.10). It is
the thickest sedimentary depocenter in the Alboran Basin, estimated to lie at a depth
between 10 and 12 km (Soto et al. 1996, 2010; Mauffret et al. 2007; Iribarren et al.
2009; Do Couto et al. 2016). Its geometry in plain view is arched, its axis mimicking
the arcuate geometry of the orogenic arc, forming a curvilinear “bean” shape that
continues toward the north to a secondary E-W basin. The northern branch has a
NE-SW trend that changes to NNW-SSE southward, from latitude 36
N. This basin
is largely affected by shale tectonics (Soto et al. 2010, 2012) and associated mud
volcanism (Pérez-Belzuz et al. 1997; Sautkin et al. 2003; Talukder et al. 2003;
Blinova et al. 2011; Somoza et al. 2012; Gennari et al. 2013).
The Motril Basin has an E-W direction, arranged approximately parallel to the
northern coast of the Alboran Sea, with a slightly trapezoidal to elongated geometry,
and its maximum thickness is greater than 4 s twtt (Fig. 5.10). The basin lies in the
eastern extension of the northern branch of the WAB, just slightly disconnected from
it (Vázquez 2001). The Intermediate Basin has no influence on the current physiography of the Alboran Sea. It is situated between the La Herradura-Djibouti Ville
Banks and the DSDP highs (Fig. 5.10). Its geometry is oval, with a maximum axis of
trend NNW-SSE. The maximum sedimentary thickness (>3.5 s twtt) is found in its
northern part. This basin could be considered as an eastern secondary marginal
sub-basin related to the main WAB. In turn, the southern sector of the Intermediate
Basin would extend to the east along the Alboran Central Trough, of NE-SW
orientation, that has a maximum thickness greater than 3 s twtt and a corridor
geometry that is highly controlled by post-Tortonian compressive processes.
The continental crust described as belonging to the North Africa domain hosts
three sedimentary basins. The longest is the SAB, located between the southern flank
of the Alboran Ridge and the Trois Fourches Promontory (Vázquez 2001), having a
NE-SW direction and a slightly trapezoidal to elongated geometry. The maximum
thicknesses (>4 s twtt—Do Couto et al. 2016; locally ~4 km of sediments—
Martínez-García et al. 2017) are located in its southwestern sector (Fig. 5.10). The
formation of this basin and its current geometry are controlled by the post-Tortonian
compressive deformation. It is separated from the WAB owing to progressive
Alboran Ridge uplift since the upper Tortonian (Martínez-García et al. 2017) by
folding and thrusting northward (Estrada et al. 2018).
Two sedimentary basins have been described to the east of the SAB: the Pytheas
and Habibas basins. The Habibas basin (at least) is floored by continental metamorphic rocks (Medaouri et al. 2012, 2014). Both basins have an elongated geometry
trending NE-SW to ENE-WSW and have an expression on the seafloor at their
northern segment. The Habibas basin has a maximum thickness close to 4.5 s twtt
(Gómez de la Peña et al. 2018) and is bounded to the north by the Yusuf Fault
(Figs. 5.4 and 5.10), to the east by the Alidade Bank, and to the west by the E
130
J.-T. Vázquez et al.