Reconstruction of the sedimentary heterogeneity in outcropping deep-water channel–levee deposits (Taza–Guercif Basin, late Tortonian, NE Morocco)

In the context of subsurface modeling of deep-water sedimentary systems, it is crucial to confidently identify turbidite channel–levee architectural elements in ancient strata. This becomes particularly critical when working with data of limited resolution, such as wireline well or seismic data. Similarly, in areas with limited outcrop exposure, establishing the temporal relationships of channel–levee systems relies predominantly on inference. Moreover, the paucity of well-documented outcrops exhibiting a continuous sedimentary record between channel-fill and overbank sediments remains a challenge.

This work presents the sedimentary architecture of channel–levee Complex 7, one of the late Tortonian (Miocene) slope channel–levee complexes constituting the Tachrift System, which records the infill of the Taza–Guercif Basin in NE Morocco. The basin was on the southern margin of an ancient seaway (the Rifian Corridor) connecting the paleo–Mediterranean Sea and the Atlantic Ocean. The objective of this study is to comprehensively document the geometry, as well as the vertical and lateral heterogeneity of facies assemblages in the northwestern part of Complex 7. This approach encompasses geological mapping, detailed facies analysis from thirty-five sedimentary logs, and the implementation of physical stratigraphic correlations.

Facies associations and stratigraphic architecture of Complex 7 reveal an eastward channel migration and a subsequent increase in flow energy.

Due to exceptional 3-D exposures, this study offers a detailed sedimentological characterization of channel fills and their correlative levee deposits. It also provides valuable insights into the evolution of the parent channel, from its formation to its abandonment, while facilitating sub-seismic-scale lithological calibration for subsurface analogs.