To aid exploration and appraisal of hydrocarbon discoveries in deepwater deposits of the Kutei Basin, a study of analogous sedimentary architectures in Recent deposits of the same basin was undertaken. High quality 3D seismic were used to develop an understanding of the external and internal geometry of slope to basin floor elements in a structured setting. Toe-thrust anticlines and related mud diapirs deflect slope canyons. Over slope-steps, gravity flow deposits are laterally confined with narrow facies belts. In slope mini-basins, flows are less confined resulting in deposition over a broad area. The Recent deposits of a single canyon and associated basin floor system are used to illustrate the deepwater depositional elements. Debrites at the base are followed by a slope channel complex or basin floor fan then a channel-levee complex. Large depocentres occur where gradients are low and the system switches from confined to unconfined. Erosionally confined channels feed basin floor fans at the toe-of-slope, while channels confined by levees feed fans on the 'distal' basin floor. Slope channel complexes and basin floor fans are interpreted to be sand prone. From the slope to basin floor these deposits increase in width:thickness ratio and areal extent and apparent lateral connectivity increases while vertical connectivity decreases.

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A detailed interpretation was undertaken to improve the description of connectivity and reservoir distribution for a field in the Campos Basin, Brazil. The Miocene reservoir was deposited in a deepwater, channelized turbidite fairway in a slope valley setting. Static pressure data acquired after production start-up indicated communication across the reservoir, but the values varied significantly, implying that the efficiency of communication varies. High-quality 3D seismic in combination with production and well data led to a hierarchical interpretation, from channel element to complex-set scale, which defined key stratigraphic and pressure surfaces. Integration of a high-repeatability 4D monitor survey showed that the 4D response changed at stratigraphic boundaries. The 4D data tied to production indicate that an aquifer is traveling along the base of the reservoir in discrete channels. The use of 4D depth shift data increased confidence in the waterfront interpretation in areas without production data. Aggradational channel complexes in the upper part of the reservoir show baffling at the margins of channel complexes down to the channel element scale. The channel elements are also likely baffled on the margins with greater connectivity downward into the lower, amalgamated unit. The lower unit shows greater lateral continuity in 4D signal, consistent with pressure data that indicate larger depletion over greater distances than the overlying aggradational complexes where producer wells are located. In summary, mapping of reservoir architecture and identification of key stratigraphic surfaces from 3D have reduced uncertainty in reservoir distribution and connectivity. Integration of 4D seismic and production data has provided confirmation of connectivity through the identification of waterfronts and unswept areas of the reservoir.