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S U M M A R Y: Slumps exposed in Tertiary sediments in Cyprus and the Spanish Pyrenees vary in inferred translation distance from metres to hundreds and possibly thousands of metres. Contractional strain initiates open to tight upright to inclined folds with hinges that are sub-parallel to the strike of the palaeoslope. This strain is produced mainly by pure shear layer parallel shortening as the slump detachment propagates, but may involve a component of simple shear strain. Downslope translation of the failed unit commonly imparts a simple shear strain which tends to tighten folds and rotate fold hinges and fold axial surfaces. Fold hinges rotate towards the downslope direction, and fold axial surfaces rotate towards parallelism with the upper and lower surfaces of the slump. Coaxially refolded folds and sheath folds may also develop. Steeply plunging folds may initiate in slumps, due to the development of steeply dipping shear zones with margins sub-parallel to the downslope direction which accommodate differential downslope movements of segments of the slump. Fold axial surface attitude and fold profile may be used as a rough estimate of the degree of fold rotation.

Palaeocene to Oligocene thrusting in the Pyrenees was synchronous with the development of the South Pyrenean foreland basin (collectively the Tremp–Graus, Ainsa and Jaca basins). Sedimentological and stratigraphical evidence from the foreland basin is used to constrain the age of movement of the Montsech, Cotiella and External Sierras thrusts. Movement on the emergent imbricate fan at the Montsech front began in the Early Eocene (Illerdian) during an early phase of thrusting that detached in the Triassic evaporites in that region. This phase of thrusting defined the Tremp–Graus basin as a thrust-sheet-top basin. Following the early thrusting, Cuisian age tectonics in the Tremp–Graus and Ainsa basins was dominated by minor normal fault movements during flexural subsidence associated with thrust sheet loading. Growth of the Boltaña anticline to the west of the Ainsa basin indicates that the Ainsa basin had become detached as a thrust-sheet-top basin in the Lutetian. Movement on the Peña Montañesa thrust, and by inference on the Cotiella thrust, began in post-Lutetian times during the propagation of lower thrusts that involved pre-Triassic (Variscan) basement. Thrusting in the External Sierras caused folding and faulting of Oligocene sediments, indicating the continued southward propagation of basement-involved thrusts in the Upper Eocene and Oligocene. Many faults in the Southern Pyrenees have evidence of early normal and later reverse senses of movement indicating reactivation of normal faults during thrusting.

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