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Although fault growth is an important control on drainage development in modern rifts, such links are difficult to establish in ancient basins. To understand how the growth and interaction of normal fault segments controls stratigraphic patterns, we investigate the response of a coarse‐grained delta system to evolution of a fault array in a Miocene half‐graben basin, Suez rift. The early Miocene Alaqa delta complex comprises a vertically stacked set of footwall‐sourced Gilbert deltas located in the immediate hangingwall of the rift border fault, adjacent to a major intrabasinal relay zone. Sedimentological and stratigraphic studies, in combination with structural analysis of the basin‐bounding fault system, permit reconstruction of the architecture, dispersal patterns and evolution of proximal Gilbert delta systems in relation to the growth and interaction of normal fault segments. Structural geometries demonstrate that fault‐related folds developed along the basin margin above upward and laterally propagating normal faults during the early stages of extension. Palaeocurrent data indicate that the delta complex formed a point‐sourced depositional system developed at the intersection of two normal fault segments. Gilbert deltas prograded transverse into the basin and laterally parallel to faults. Development of the transverse delta complex is proposed to be a function of its location adjacent to an evolving zone of fault overlap, together with focusing of dispersal between adjacent fault segments growing towards each other. Growth strata onlap and converge onto the monoclinal fold limbs indicating that these structures formed evolving structural topography. During fold growth, Gilbert deltas prograded across the deforming fold surface, became progressively rotated and incorporated into fold limbs. Spatial variability of facies architecture is linked to along‐strike variation in the style of fault/fold growth, and in particular variation in rates of crestal uplift and fold limb rotation. Our results clearly show that the growth and linkage of fault segments during fault array evolution has a fundamental control on patterns of sediment dispersal in rift basins.

The Barremian–Aptian upper Khami Group and Albian–Campanian Bangestan Group have been studied at outcrop in Lurestan, SW Iran. The upper Khami Group comprises a thin deltaic wedge (Gadvan Fm) transgressively overlain by shelfal carbonates (Dariyan Fm). The Dariyan Fm can be divided into lower and upper units separated by a major intra-Aptian fracture-controlled karst. The top of the Daryian Fm is capped by the Arabian plate-wide Aptian–Albian unconformity. The overlying Bangestan Group includes the Kazhdumi, Sarvak, Surgah and Ilam formations. The Kazhdumi Fm represents a mixed carbonate-clastic intrashelf basin succession, and passes laterally (towards the NE) into a low-angle Orbitolina-dominated muddy carbonate ramp/shoal (Mauddud Mbr). The Mauddud Mbr is capped by an angular unconformity and karst of latest Albian–earliest Cenomanian age. The overlying Sarvak Fm comprises both low-angle ramp and steeper dipping (5–10°) carbonate shelf/platform systems. Three regionally extensive karst surfaces are developed in the latest Cenomanian–Turonian interval of the Sarvak Fm, and are interpreted to be related to flexure of the Arabian plate margin due to the initiation of intra-oceanic deformation. The Surgah and Ilam Fm represent clastic and muddy carbonate ramp depositional systems respectively.Both The Khami and Bangestan groups have been affected by spectacularly exposed fracture-controlled dolomitization. Dolomite bodies are 100 m to several km in width, have plume-like geometry, with both fracture (fault/joint) and gradational diagenetic contacts with undolomitized country rock. Sheets of dolomite extend away from dolomite bodies along steeply dipping fault/joint zones, and as strata-bound bodies preferentially following specific depositional/diagenetic facies or stratal surfaces. There is a close link between primary depositional architecture/facies and secondary dolomitization. Vertical barriers to dolomitization are low permeability mudstones, below which dolomitizing fluids moved laterally. Where these barriers are cut by faults and fracture corridors, dolomitization can be observed to have advanced upwards, indicating that faults and joints were fluid migration conduits.Comparisons to Jurassic–Cenozoic dolomites elsewhere in Iran, Palaeozoic dolomites of North America and Neogene dolomites of the Gulf of Suez indicate striking textural, paragenetic and outcrop-scale similarities. These data imply a common fracture-controlled dolomitization process is applicable regardless of tectonic setting (compressional, transtensional and extensional).

A summary and discussion is given of alternative models of the tectonic evolution of the Tethyan orogenic belt in the Eastern Mediterranean region, based on recent information. Model 1 (Robertson & Dixon 1984). A single Tethyan ocean continuously existed in the Eastern Mediterranean region, at least from Late Palaeozoic onwards. The dominant influences were episodic northward subduction of Tethyan oceanic crust beneath Eurasia, and the northward drift of continental fragments, from Gondwana towards Eurasia. During the Mesozoic, the south Tethyan area was interspersed with Gondwana-derived microcontinents and small ocean basins. Ophiolites formed mainly by spreading above subduction zones in both northerly (internal) and southerly (external) oceanic basins during times of regional plate convergence, and were mainly emplaced as a result of trench-passive margin collisions. In a related model, Stampfli et al. (1991) argued for spreading along the North African margin in the Late Permian. Model 2A (Dercourt et al. 1986). Only one evolving Tethys existed. Triassic-Jurassic oceanic crust (Neotethys) formed in a single Tethyan ocean basin located north of Gondwana-related units. Spreading later formed a small ocean basin in the present Eastern Mediterranean Sea area during the Cretaceous. Jurassic and Cretaceous ophiolites formed at spreading ridges and record times of regional plate divergence. In an update version, Model 2B (Dercourt et al. 1993), spreading extended along the northern margin of Gondwana, with an arm extending through the south Aegean, splitting off a large microcontinent. Further spreading in the Cretaceous then opened the Eastern Mediterranean basin and fragmented pre-existing carbonate platforms. The Mesozoic ophiolites were seen as being mainly far-travelled from northerly (i.e. internal) orogenic areas. Model 3 (Şengör et al. 1984). Subduction in the Late Palaeozoic was dominantly southwards, beneath the northern margin of Gondwana in the Eastern Mediterranean. This subduction led to opening of Triassic backarc basins; and a rifted Gondwana fragment (Cimmeria) drifted across a pre-existing Tethys (Palaeo-Tethys) to collide with a passive Eurasian margin. In their model, a backarc basin (Karakaya Basin) rifted and then closed prior to collision of a Cimmerian microcontinent in the Mid Jurassic, and this was followed by renewed rifting of a small ocean basin in the Early Jurassic. Mesozoic ophiolites mainly formed above subduction zones; they were variously seen as far-travelled (in the ‘Greek area’), or more locally rooted (in the ‘Turkish area’). Recent evidence shows that difficulties exist in detail with all three models. However, four key elements are met in Model 1: dominantly northward subduction in the north; multiple ocean basins from Triassic onwards in the south; supra-subduction spreading of the major ophiolites; and emplacement from both northerly and southerly Mesozoic oceanic basins. Palaeomagnetism has played an important role, in setting the large-scale Africa-Eurasia relative motion framework and in providing tests for the tectonic affinities of smaller units, but such smaller-scale studies have often been compromised by the geological complexity and by the remagnetisation of tectonically thickened units.