The Southern Uplands contain 10 or more distinct deep-water stratigraphic sequences consisting of basalt and chert and/or graptolitic shale, below thick greywackes. These sequences are separated by major reverse strike faults. Adjacent sequences differ in sedimentary characteristics and age, indicating that they were originally deposited far apart. Within each fault-bounded tract the individual sequences are disrupted and repeated by further, less important, strike faults and by folding. In the N (away from the site of the Iapetus Ocean) the sequences are older than in the S, but the majority of the beds within each sequence young to the N. This structure is compared with modern accretionary prisms, which develop on active continental margins where the oceanic plate has a thick sedimentary cover.

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In the late Silurian,

The Makran is a broadly east–west trending arcuate accretionary wedge currently forming where the oceanic floor of the Gulf of Oman is being subducted north‐northeastward beneath the south Asian margin. Two traverses across the Makran Coast Ranges, extending about 80 km inland from the coastline (which lies about 100 km north of the wedge front), show that the structure of this region is dominated by large back‐rotated south directed thrust faults and associated folds. Related structures include duplexes, fault gouge containing Reidel shears, and melange along fault zones. These structures are cut by later north directed backthrusts, out‐of‐sequence south directed thrusts, and apparently conjugate sets of NNE trending sinistral and NW trending dextral strike‐slip faults. Slip vectors were determined from slickenlines, fiber lineations, gouge fabrics, and Riedel shears. Vectors from early thrusts and bedding‐parallel slip surfaces, corrected for tectonic rotation, form a broad south directed concentration lying between the normal to the regional strike (varying from 160° to 180°) and the present plate convergence vector (200°). Locally, the concentration is bimodal. This pattern may represent the interaction between plate forces and body forces in the accretionary wedge. The late thrusts have widely variable slip vectors and stair‐step off the early thrusts. They overlap in orientation and slip vector with gently dipping sinistral strike‐slip faults, suggesting that they also stair‐step in plan off the latter. The steep strike‐slip faults represent the final tectonic stage, involving minor N‐S shortening and longitudinal extension. These three stages probably occurred in sequence in any one area but migrated diachronously southward as the wedge grew.