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Extensive magnetic fabric investigations have been conducted on the Late Jurassic sedimentary black shales (37 sites, 362 samples), the so-called Terres Noires Formation, from the Southern Subalpine Chains (western Alps). This study completes a previous study done in the Northern Subalpine Chains which demonstrated that the Terres Noires Formation preserves a subtle magnetic lineation related to tectonic transport direction. In the Southern Subalpine Chains (Diois, Devoluy, Embrunais, Digne nappe), similar magnetic fabrics have been found. The shape of the magnetic fabric is oblate and locally mirrors the gradient of deformation in the Embrunais footwall. The magnetic foliation is parallel to the bedding or to the slaty cleavage. About 50% of the magnetic lineations have down-dip magnetic directions while the other magnetic lineations are sub-horizontal or parallel to the intersection bedding/cleavage. The tectonic magnetic fabrics recorded in the Embrunais confirm the ability of the Terres Noires to record tectonic transport direction. The magnetic fabric geometry suggests SW-directed tectonic transport in the Southern Subalpine Chains. The Diois appears as a tip zone where transport directions are abruptly clockwise rotated from NW-directed in the Northern Subsalpine Chains to SW-directed. The magnetic fabric from the Digne nappe exhibits a fan pattern of transport directions in close agreement with the arcuate shape of the thrust.

The Ivory Coast-Ghana (ICG) marginal ridge is a prominent feature of the ICG transform margin and includes a fossil ridge partially buried by a thick, undeformed sedimentary cover. The fossil ICG ridge is 130 km long and 25 km wide, and towers over the adjacent rifted basin (deep Ivorian basin, DIB) and the oceanic crust by 1.3 km and more than 4 km, respectively. It formed in three successive stages. 1. (1) During the rifting of the DIB, both vertical and horizontal motions between the DIB and the South American plate varied along the plate boundary. This relative motion occurred in an accommodation zone that tilted the northern slope of the ICG ridge along en-echelon, mainly strike-slip, faults. 2. (2) After the rifting of the DIB, the relative motion remained constant along the transform plate boundary. At this time strike-slip deformation was localized into a narrow and highly deformed belt that truncated the accommodation zone. 3. (3) Finally, the transform motion occurred between the DIB and an occanic plate. Thermal exchanges between the two adjacent plates induced thermal uplift of the ICG ridge that amplified previous tectonic tilting.

Detailed study of microfaults and associated striated fault planes affecting the Early Cretaceous infilling of Rio do Peixe basins (northeast Brazil) allows us to determine a regional stress field with a NNW-SSE oriented extensional component. In the basement, reactivated E-W and NE-SW ductile shear zones of Pan-African age both controlled the architecture and elongation of the basins. These en-echelon half-grabens illustrate the first stages of intracontinental rifting of a pre-fractured crust. During the Early Cretaceous, the northeast Brazilian province was subjected to NW-SE extension related to the eastward opening of the South Atlantic ocean.