The Tanqua area of the Karoo basin, South Africa, contains five Permian deep‐water turbidite fan systems, almost completely exposed over some 640 km2. Reconstruction of the basin‐fill and fan distributions indicates a progradational trend in the 450 m+ thick succession, from distal basin floor (fan 1) through basin‐floor subenvironments (fans 2, 3 and 4) to a slope setting (fan 5). Fans are up to 65 m thick with gradational to sharp bases and tops. Facies associations include basin plain claystone and distal turbidite siltstone/claystone and a range of fine‐grained sandstone associations, including low‐ and high‐density turbidite current deposits and proportionally minor debris/slurry flows. Architectural elements include sheets of amalgamated and layered styles and channels of five types. Each fan is interpreted as a low‐frequency lowstand systems tract with the shaly interfan intervals representing transgressive and highstand systems tracts. All fans show complex internal facies distributions but exhibit a high‐frequency internal stratigraphy based on fan‐wide zones of relative sediment starvation. These zones are interpreted as transgressive and highstand systems tracts of higher order sequences. Sandy packages between these fine‐grained intervals are interpreted as high‐frequency lowstand systems tracts and exhibit dominantly progradational stacking patterns, resulting in subtle downdip clinoform geometries. Bases of fans and intrafan packages are interpreted as low‐ and high‐frequency sequence boundaries respectively. Facies juxtapositions across these sequence boundaries are variable and may be gradational, sharp or erosive. In all cases, criteria for a basinward shift of facies are met, but there is no standard ‘motif’ for sequence boundaries in this system. High‐frequency sequences represent the dominant mechanism of active fan growth in the Tanqua deep‐water system.

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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.

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Analysis of extensive exposures of the Permian Laingsburg Formation, Karoo basin, South Africa, have enabled a detailed reconstruction of the base of slope stratigraphy and palaeoenvironments in a deep‐water system characterized by a very narrow grain‐size range (fine sandstone). The deposits include an ≈ 4 km wide and 80 m thick channel complex, fringed by sandy sheet deposits that extend laterally for at least 6 km across depositional strike. Within the channel complex, individual channel fills are marked by shallow basal erosion surfaces draped by thin, parallel‐stratified beds of very fine sandstone and siltstone, interpreted as flow tails to largely bypassing flows. These thin beds are overlain by 0·4 to 5 m thick beds of structureless, fine‐grained sandstone that represent the majority of the channel fills. The basal packages may be partially to completely removed by localized scour in the axial zone of the channel complex but can be mapped laterally into overbank areas where they thicken and are dominated by rippled fine sandstones with intercalated siltstones. Axial confinement resulted from subtle topography on the basin floor, whereby the lower, dense parts of the initially erosive and bypassing flows were partially confined in the lows and the more dilute, slower moving upper parts of the flows deposited sheet‐like successions across slightly elevated overbank areas. The narrow grain‐size distribution prohibited the formation ofcoarse‐grained residual bypass deposits during the initial phases of channel formation. With decreasing magnitude, later flows became more depositional, filling remaining axial depressions with thick‐bedded structureless sandstone. The smaller volumes of late‐stage sediment were more axially focused, producing local scour‐and‐fill features and starvation of the overbank areas. Resulting grain‐size vertical profiles are complex. The basal flow tail packages and overlying massive deposits form a thickening and slightly coarsening‐upward trend in the channel fills. The overbank deposits show a thinning‐ and fining‐upward profile as a result of less bypass plus late‐stage starvation of sand. Application of traditional deep‐water facies models could therefore potentially lead to erroneous interpretations of the channel complex as a prograding lobe and the overbank sheets as channel‐fills.

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The authors surveyed by telephone a random sample of voters in the 1996 presidential election from the Standard Metropolitan Statistical Area of Muncie, IN ("Middletown"; R. Lynd & H. Lynd, 1929) to test a model describing the nature of 2 conservative political ideologies--social traditionalism and economic conservatism. The model, based on functions of attitudes theory, predicted (a) that the 2 political ideologies would appeal to 2 rather distinct constituency groups--the former, to conservative Protestants; the latter, to people of higher incomes--and (b) that social traditionalists would be more dogmatic and economic conservatives would be more open-minded in their respective views. The findings were consistent with those predictions.