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Overthe last decade comprehensiveexploration for turbiditeplays hasbeenrewarded byasignificant numberofhydrocarbon discoveries. However,the industry isstill critically challenged withrespecttoappropriate andrefined prediction ofsand/shaled istributions withint hesed epositionals ystems. Alongwithastronga nd sustained commercialinterest intheseplays,extensivesubsurface datasets,includinganewgeneration ofcoreandwell/log-calibrated seismic faciessuites,havebecomeavailable.Based on thisv aluablei nformation,systematic 2Da nd3Dseismic sequence stratigraphicalanalysisw ith particularfocus on seismic faciesandseismic geomorphologywasperformed infivedifferent basins alongNorth andSouthAtlantic margins. Each subsurface examplewascharacterized withreference to its relativesequence stratigraphic orderw ithinah ierarchy. Evolvingg eologicalp arameters like shelfa ccommodation,shelf-break position,slopegradient,slopeandbasinbathymetry/topographyandthird-, fourth-andoccasionally fifth-order stackingpatterns wereassessed withinsecond-ordercyclesineach case.Based on theseobservations,recognition criteria for subsurface lithologyp rediction wered erived.Conceptualknowledgef rom outcrop analysisw asan essentialandintegralpart ofthe interpretation process throughout the study.The subsurface recognition criteria, highlighted inthisstudy,emphasizesimilarity andvariability betweentwo end-memberbasins tyles:h igh shelf-to-basinr elief/sediment under-filled basins wheresand-pronenearshore systems don ot prograde overdeep-waterfans ystems inasecond-ordercyclec ontext; low shelf-to-basin relief/sediment over-filled basins wheresand-pronenearshoresystems doprograde overdeep-waterfansystems inasecond-ordercyclecontext.The most strikingc ontrast withrespectt odeep-waterr eservoirs andstoned istribution int he two basin categoriesrelatestothe fourth-andfifth-orderstackingpatterns offanbuilding-block cycleswithinsecond-and third-ordercycles,which tendto show low progradation/aggradation ratioint he high relief basins andh igh progradation/aggradation ratioint he low relief basins. Givenanu nderstandingofg eologicalcontext,these seismically identifiablepatterns provide morea ccurateprediction ofsanda ndshaled istribution withindeepwaterclastic systems.

The Shelf Edge and Shoreline Trajectories Conference, convened in Tromsø, Norway, during the autumn of 2007, was attended by a group of specialists working in the crossover between industry and academia. This paper introduces the concepts of shelf edge‐ and shoreline‐trajectory analysis, and discusses some of the advantages of applying such concepts in contrast to more traditional sequence stratigraphic analysis. This special issue of Basin Research focuses on how observations of outcrop and subsurface datasets, particularly three‐dimensional (3D) seismic data, may be used as an aid to identify palaeo‐shelf edges and shorelines. Moreover, the approach shows how linking the cross‐sectional path of a shoreline as it migrates (shoreline trajectory) and the pathway taken by the shelf‐edge during the development of a series of accreting clinoforms (shelf‐edge trajectory) to the analysis of sedimentological or seismic facies can improve predictions of lithology distribution. The following 15 papers present well‐documented case studies from a variety of shelf and shelf‐margin settings where these concepts have been applied to depositional systems ranging in age from Permian to Recent. A wide spectrum of data types and methods, including two dimensional and 3D seismic data, well logs and core material as well as high‐resolution biostratigraphy, outcrop studies and modern bathymetric data have been applied in the various papers. Despite the considerable age range of the deposits investigated and the data types used for the studies, all of the authors have converged towards the objective approach of trajectory analysis. However, any analytical method has some uncertainty attached to it, and a discussion of possible pitfalls and sources of error is also a part of this introductory paper. Although this special issue presents some recent advances in the way to conduct stratigraphic analysis, we realise that this is only a further step in an evolving discipline. Development of sequence stratigraphic concepts will continue, and new contributions will evaluate past work as they seek to develop the subject.

A Middle to Late Miocene compression phase has been documented along the Norwegian margin from 62°N to 68°N. Reverse faults and inversion domes are numerous on the 300 to 450km wide central mid-Norwegian margin, but are only locally observed on the Møre and Lofoten margins. A major regression forced the coastline of the syn-tectonic Kai Formation 50–150km west of the present coastline and a genetic link between the regression and the smaller-scale contraction structures is observed. Long wavelength (200–300 km) lithospheric bulging is suggested to explain the coastline regression at the onset of the compression phase. The position of the regressed coastline suggests that the continent–shelf transition guides the lithospheric buckling such that the thicker crust segment is uplifted. Long wavelength folding may account for additional crustal shortening along the sharp crustal transitions on the Lofoten and Møre margins. It is suggested that the Norwegian onshore domes were formed during at least two independent stages – a Middle to late Miocene compression related uplift and later regional glacial isostatic uplift. The syn-tectonic Kai Formation fills in the depressions around the contraction-related structures and is dated as late Middle to Late Miocene. It is suggested that both the Utsira Formation and the assumed northern equivalent, the Molo Formation, were deposited after the compression event and, thus, are mainly early Pliocene in age. The Middle to Late Miocene compression phase is observed throughout the North Atlantic and the sea-level fall at the initiation and rise at the termination corresponds with significant shifts in climate.

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