Salt tectonics in the Atlantic margin of Morocco

Abstract

The offshore basins of Morocco's Atlantic margin represent the westernmost exploration frontier area in North Africa (Figure 1). Whereas the presence of an active petroleum system is very well established onshore (e.g., Essaouira Basin), only promising oil shows and one minor oil accumulation have been found to date offshore (e.g., Tarfaya Basin). However, all previous exploration effort concentrated only on the shelfal region and therefore it should not be very surprising that several blocks were licensed in the last few years covering large offshore acreage in water depths to almost 3000 m (Figure 1). As the reconnaissance licenses for these permits are in the process of being converted to exploration licenses, a shift from regional-scale 2-D seismic reflection data acquisition to prospect-scale 2-D and even 3-D is under way. Figure 1. Index map of the Atlantic margin of Morocco showing location of a regional cross-section (Figure 2) and simplified salt tectonics map (Figure 3). An active petroleum system is not proven in the deepwater region although a broad, world-class salt basin stretches along the coastline creating spectacular structural traps. The first deepwater well might be spudded as early as next year to test one of these salt-related structures. A potential target zone within the deepwater salt basin is at the westernmost, leading edge of the salt deformational front where a very well developed toe-thrust zone formed during the mid-Tertiary. The salt tectonics of offshore Morocco may provide some very specific analogs for exploration efforts in other salt basins of the world. Perhaps the easiest way to understand the scale of the salt basin offshore Morocco is to compile regional seismic transects. Figure 2 shows a line drawing of a regional composite seismic profile across the Ras Tafelney and Safi Haute Mer permits (Figure 1). Note that the Atlantic passive margin of …