Sedimentary slide deformation structures in the Lower Carboniferous (Dinantian) sediments of the Bowland basin show a spoon-shaped morphology with extension in the head region and compression in the toe. The particular structures developed depend on the rheological properties of the sediment involved. Slides in soft sediment have deformation distributed throughout the slide mass, with folding being the dominant deformation style. Slides within more lithified sediment have deformation concentrated along slip planes. Both types of deformation may be present within a particular slide, depending on diagenetic factors and the depth to which slide planes cut down. Disaggregation of slides to yield material for sediment gravity flows is explained by processes operating within the slide unit.

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The Coloso Formation is an early Cretaceous conglomerate-dominated molasse sequence in northern Chile. The sequence was deposited rapidly and records the unroofing of granodioritic and andesitic source rocks. Thin sand units throughout the sequence have been studied palaeomagnetically; the results are complex but can be related to the diagenesis of and-zone alluvium. Natural remanent magnetization (NRM) may be normal or reversed but is usually a combination of the two. Isolation of magnetic components by vector analysis of thermal and A F demagnetization data yields both normal and reversed components which are approximately antiparallel and yield an average pole position at 703, 192"E. This is consistent with late Cretaceous data from northern Chile but not with the established apparent polar wander (APW) path for South America. It may indicate late Cretaceous remagnetization but is considered to be more likely an indication that the present APW path assumes no tectonic rotation and that important relative movements have taken place between northern Chile and Argentina.

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The ENE-WSW-trending North Solway Fault acted as a northern marginal fault to the Solway Basin during Dinantian sedimentation. Structural, sedimentological and diagenetic relationships suggest syn-sedimentary Dinantian movement was dip-slip and normal. A later Carboniferous phase of dextral transtension is also indicated. Allokinetic deformation features increase in abundance and intensity towards the North Solway Fault, their presence and nature being strongly facies dependent. Syn-sedimentary fault deformation of the hanging wall sediments also increases towards this fault. Both distributed and localized shearing characterizes these early faults and is thought to be related to the water content of beds at the time of deformation. Local minor thrusting and reverse fault movement also occurred within the sediments during basin extension, due to dextral transtensional movement on the North Solway Fault. N-S-and NW-SE-trending faults appear to show no evidence for syn-sedimentary Dinantian movement and are interpreted as the products of 'Hercynian' basin shortening and Mesozoic basin formation.